first commit

group/amd/build/comboboxsearch/group.min.js

@@ -0,0 +1,3 @@
+define("core_group/comboboxsearch/group",["exports","core/comboboxsearch/search_combobox","core_group/comboboxsearch/repository","core/templates","core/utils","core/notification"],(function(_exports,_search_combobox,_repository,_templates,_utils,_notification){function _interopRequireDefault(obj){return obj&&obj.__esModule?obj:{default:obj}}function _defineProperty(obj,key,value){return key in obj?Object.defineProperty(obj,key,{value:value,enumerable:!0,configurable:!0,writable:!0}):obj[key]=value,obj}Object.defineProperty(_exports,"__esModule",{value:!0}),_exports.default=void 0,_search_combobox=_interopRequireDefault(_search_combobox),_notification=_interopRequireDefault(_notification);class GroupSearch extends _search_combobox.default{constructor(){super(),_defineProperty(this,"courseID",void 0),_defineProperty(this,"bannedFilterFields",["id","link","groupimageurl"]),this.selectors={...this.selectors,courseid:'[data-region="courseid"]',placeholder:'.groupsearchdropdown [data-region="searchplaceholder"]'};const component=document.querySelector(this.componentSelector());this.courseID=component.querySelector(this.selectors.courseid).dataset.courseid,this.instance=component.querySelector(this.selectors.instance).dataset.instance;const searchValueElement=this.component.querySelector("#".concat(this.searchInput.dataset.inputElement));searchValueElement.addEventListener("change",(()=>{this.toggleDropdown();const valueElement=this.component.querySelector("#".concat(this.combobox.dataset.inputElement));valueElement.value!==searchValueElement.value&&(valueElement.value=searchValueElement.value,valueElement.dispatchEvent(new Event("change",{bubbles:!0}))),searchValueElement.value=""})),this.$component.on("hide.bs.dropdown",(()=>{this.searchInput.removeAttribute("aria-activedescendant");const listbox=document.querySelector("#".concat(this.searchInput.getAttribute("aria-controls"),'[role="listbox"]'));listbox.querySelectorAll('.active[role="option"]').forEach((option=>{option.classList.remove("active")})),listbox.scrollTop=0,setTimeout((()=>{""!==this.searchInput.value&&(this.searchInput.value="",this.searchInput.dispatchEvent(new Event("input",{bubbles:!0})))}))})),this.renderDefault().catch(_notification.default.exception)}static init(){return new GroupSearch}componentSelector(){return".group-search"}dropdownSelector(){return".groupsearchdropdown"}async renderDropdown(){const{html:html,js:js}=await(0,_templates.renderForPromise)("core_group/comboboxsearch/resultset",{groups:this.getMatchedResults(),hasresults:this.getMatchedResults().length>0,instance:this.instance,searchterm:this.getSearchTerm()});(0,_templates.replaceNodeContents)(this.selectors.placeholder,html,js),this.searchInput.removeAttribute("aria-activedescendant")}async renderDefault(){this.setMatchedResults(await this.filterDataset(await this.getDataset())),this.filterMatchDataset(),await this.renderDropdown(),this.updateNodes()}async fetchDataset(){return await(0,_repository.groupFetch)(this.courseID).then((r=>r.groups))}async filterDataset(filterableData){return""===this.getPreppedSearchTerm()?filterableData:filterableData.filter((group=>Object.keys(group).some((key=>""!==group[key]&&!this.bannedFilterFields.includes(key)&&group[key].toString().toLowerCase().includes(this.getPreppedSearchTerm())))))}filterMatchDataset(){this.setMatchedResults(this.getMatchedResults().map((group=>({id:group.id,name:group.name,groupimageurl:group.groupimageurl}))))}async clickHandler(e){e.target.closest(this.selectors.clearSearch)&&(e.stopPropagation(),this.searchInput.value="",this.setSearchTerms(this.searchInput.value),this.searchInput.focus(),this.clearSearchButton.classList.add("d-none"),await this.filterrenderpipe())}changeHandler(e){window.location=this.selectOneLink(e.target.value)}registerInputHandlers(){this.searchInput.addEventListener("input",(0,_utils.debounce)((async()=>{this.setSearchTerms(this.searchInput.value),""===this.getSearchTerm()?this.clearSearchButton.classList.add("d-none"):this.clearSearchButton.classList.remove("d-none"),await this.filterrenderpipe()}),300))}selectOneLink(groupID){throw new Error("selectOneLink(".concat(groupID,") must be implemented in ").concat(this.constructor.name))}}return _exports.default=GroupSearch,_exports.default}));
+
+//# sourceMappingURL=group.min.js.map

group/amd/build/comboboxsearch/repository.min.js

@@ -0,0 +1,10 @@
+define("core_group/comboboxsearch/repository",["exports","core/ajax"],(function(_exports,_ajax){var obj;
+/**
+   * A repo for the comboboxsearch group type.
+   *
+   * @module    core_group/comboboxsearch/repository
+   * @copyright 2023 Mathew May <mathew.solutions>
+   * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+   */Object.defineProperty(_exports,"__esModule",{value:!0}),_exports.groupFetch=void 0,_ajax=(obj=_ajax)&&obj.__esModule?obj:{default:obj};_exports.groupFetch=courseid=>{const request={methodname:"core_group_get_groups_for_selector",args:{courseid:courseid}};return _ajax.default.call([request])[0]}}));
+
+//# sourceMappingURL=repository.min.js.map

group/amd/build/comboboxsearch/repository.min.js.map

@@ -0,0 +1 @@
+{"version":3,"file":"repository.min.js","sources":["../../src/comboboxsearch/repository.js"],"sourcesContent":["// This file is part of Moodle - http://moodle.org/\n//\n// Moodle is free software: you can redistribute it and/or modify\n// it under the terms of the GNU General Public License as published by\n// the Free Software Foundation, either version 3 of the License, or\n// (at your option) any later version.\n//\n// Moodle is distributed in the hope that it will be useful,\n// but WITHOUT ANY WARRANTY; without even the implied warranty of\n// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n// GNU General Public License for more details.\n//\n// You should have received a copy of the GNU General Public License\n// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.\n\n/**\n * A repo for the comboboxsearch group type.\n *\n * @module    core_group/comboboxsearch/repository\n * @copyright 2023 Mathew May <mathew.solutions>\n * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later\n */\n\nimport ajax from \"core/ajax\";\n\n/**\n * Given a course ID, we want to fetch the groups, so we may fetch their users.\n *\n * @method groupFetch\n * @param {int} courseid ID of the course to fetch the users of.\n * @return {object} jQuery promise\n */\nexport const groupFetch = (courseid) => {\n    const request = {\n        methodname: 'core_group_get_groups_for_selector',\n        args: {\n            courseid: courseid,\n        },\n    };\n    return ajax.call([request])[0];\n};\n"],"names":["courseid","request","methodname","args","ajax","call"],"mappings":";;;;;;;gKAgC2BA,iBACjBC,QAAU,CACZC,WAAY,qCACZC,KAAM,CACFH,SAAUA,kBAGXI,cAAKC,KAAK,CAACJ,UAAU"}

group/amd/build/grouppicker.min.js

@@ -0,0 +1,9 @@
+define("core_group/grouppicker",["exports"],(function(_exports){Object.defineProperty(_exports,"__esModule",{value:!0}),_exports.default=void 0;return _exports.default=
+/**
+   * @module     core_group/groupPicker
+   * @copyright  2022 Matthew Hilton <matthewhilton@catalyst-au.net>
+   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+   */
+class{constructor(){let elementId=arguments.length>0&&void 0!==arguments[0]?arguments[0]:"groups";const pickerDomElement=document.getElementById(elementId);if(!pickerDomElement)throw new Error("Groups picker was not found.");this.element=pickerDomElement}getDomElement(){return this.element}getSelectedValues(){return Array.from(this.element.querySelectorAll("option:checked")).map((el=>parseInt(el.value)))}},_exports.default}));
+
+//# sourceMappingURL=grouppicker.min.js.map

group/amd/build/grouppicker.min.js.map

@@ -0,0 +1 @@
+{"version":3,"file":"grouppicker.min.js","sources":["../src/grouppicker.js"],"sourcesContent":["// This file is part of Moodle - http://moodle.org/\n//\n// Moodle is free software: you can redistribute it and/or modify\n// it under the terms of the GNU General Public License as published by\n// the Free Software Foundation, either version 3 of the License, or\n// (at your option) any later version.\n//\n// Moodle is distributed in the hope that it will be useful,\n// but WITHOUT ANY WARRANTY; without even the implied warranty of\n// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n// GNU General Public License for more details.\n//\n// You should have received a copy of the GNU General Public License\n// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.\n/**\n * @module     core_group/groupPicker\n * @copyright  2022 Matthew Hilton <matthewhilton@catalyst-au.net>\n * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later\n */\n\n/**\n * Class used for interfacing with the group select picker.\n *\n * @class core_group/GroupPicker\n */\nexport default class GroupPicker {\n    /**\n     * Creates the group picker class and finds the corresponding DOM element.\n     *\n     * @param {String} elementId The DOM element id of the <select> input\n     * @throws Error if the element was not found.\n     */\n    constructor(elementId = \"groups\") {\n        const pickerDomElement = document.getElementById(elementId);\n\n        if (!pickerDomElement) {\n            throw new Error(\"Groups picker was not found.\");\n        }\n\n        this.element = pickerDomElement;\n    }\n\n    /**\n     * Returns the DOM element this class is linked to.\n     *\n     * @returns {HTMLElement} The DOM element\n     */\n    getDomElement() {\n        return this.element;\n    }\n\n    /**\n     * Returns the selected group values.\n     *\n     * @returns {Number[]} The group IDs that are currently selected.\n     */\n    getSelectedValues() {\n        const selectedOptionElements = Array.from(this.element.querySelectorAll(\"option:checked\"));\n        const selectedGroups = selectedOptionElements.map(el => parseInt(el.value));\n\n        return selectedGroups;\n    }\n}\n"],"names":["constructor","elementId","pickerDomElement","document","getElementById","Error","element","getDomElement","this","getSelectedValues","Array","from","querySelectorAll","map","el","parseInt","value"],"mappings":";;;;;;MAgCIA,kBAAYC,iEAAY,eACdC,iBAAmBC,SAASC,eAAeH,eAE5CC,uBACK,IAAIG,MAAM,qCAGfC,QAAUJ,iBAQnBK,uBACWC,KAAKF,QAQhBG,2BACmCC,MAAMC,KAAKH,KAAKF,QAAQM,iBAAiB,mBAC1BC,KAAIC,IAAMC,SAASD,GAAGE"}

group/amd/build/index.min.js

@@ -0,0 +1,8 @@
+define("core_group/index",["exports","./grouppicker"],(function(_exports,_grouppicker){var obj;
+/**
+   * @module     core_group/index
+   * @copyright  2022 Matthew Hilton <matthewhilton@catalyst-au.net>
+   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+   */Object.defineProperty(_exports,"__esModule",{value:!0}),_exports.updateBulkActionButtons=_exports.setElementEnabled=_exports.init=void 0;const groupPicker=new(_grouppicker=(obj=_grouppicker)&&obj.__esModule?obj:{default:obj}).default;_exports.init=()=>{groupPicker.getDomElement().addEventListener("change",updateBulkActionButtons),updateBulkActionButtons()};const updateBulkActionButtons=()=>{const aGroupIsSelected=0!==groupPicker.getSelectedValues().length,bulkActionsEnabledStatuses={enablemessaging:aGroupIsSelected,disablemessaging:aGroupIsSelected};Object.entries(bulkActionsEnabledStatuses).map((_ref=>{let[buttonId,enabled]=_ref;return setElementEnabled(buttonId,enabled)}))};_exports.updateBulkActionButtons=updateBulkActionButtons;const setElementEnabled=(domElementId,enabled)=>{const element=document.getElementById(domElementId);element&&(enabled?element.removeAttribute("disabled"):element.setAttribute("disabled","disabled"))};_exports.setElementEnabled=setElementEnabled}));
+
+//# sourceMappingURL=index.min.js.map

group/amd/build/index.min.js.map

@@ -0,0 +1 @@
+{"version":3,"file":"index.min.js","sources":["../src/index.js"],"sourcesContent":["// This file is part of Moodle - http://moodle.org/\n//\n// Moodle is free software: you can redistribute it and/or modify\n// it under the terms of the GNU General Public License as published by\n// the Free Software Foundation, either version 3 of the License, or\n// (at your option) any later version.\n//\n// Moodle is distributed in the hope that it will be useful,\n// but WITHOUT ANY WARRANTY; without even the implied warranty of\n// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n// GNU General Public License for more details.\n//\n// You should have received a copy of the GNU General Public License\n// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.\n/**\n * @module     core_group/index\n * @copyright  2022 Matthew Hilton <matthewhilton@catalyst-au.net>\n * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later\n */\n\nimport GroupPicker from \"./grouppicker\";\n\nconst groupPicker = new GroupPicker();\n\n/**\n * Initialise page.\n */\nexport const init = () => {\n    // Init event listeners.\n    groupPicker.getDomElement().addEventListener(\"change\", updateBulkActionButtons);\n\n    // Call initially to set initial button state.\n    updateBulkActionButtons();\n};\n\n/**\n * Updates the bulk action buttons depending on specific conditions.\n */\nexport const updateBulkActionButtons = () => {\n    const groupsSelected = groupPicker.getSelectedValues();\n    const aGroupIsSelected = groupsSelected.length !== 0;\n\n    // Collate the conditions where each button is enabled/disabled.\n    const bulkActionsEnabledStatuses = {\n        'enablemessaging': aGroupIsSelected,\n        'disablemessaging': aGroupIsSelected\n    };\n\n    // Update the status of each button.\n    Object.entries(bulkActionsEnabledStatuses).map(([buttonId, enabled]) => setElementEnabled(buttonId, enabled));\n};\n\n/**\n * Adds or removes the given element's disabled attribute.\n * @param {string} domElementId ID of the dom element (without the #)\n * @param {bool} enabled If false, the disable attribute is applied, else it is removed.\n */\nexport const setElementEnabled = (domElementId, enabled) => {\n    const element = document.getElementById(domElementId);\n\n    if (!element) {\n        // If there is no element, we do nothing.\n        // The element could be purposefully hidden or removed.\n        return;\n    }\n\n    if (!enabled) {\n        element.setAttribute('disabled', 'disabled');\n    } else {\n        element.removeAttribute('disabled');\n    }\n};\n"],"names":["groupPicker","getDomElement","addEventListener","updateBulkActionButtons","aGroupIsSelected","getSelectedValues","length","bulkActionsEnabledStatuses","Object","entries","map","_ref","buttonId","enabled","setElementEnabled","domElementId","element","document","getElementById","removeAttribute","setAttribute"],"mappings":";;;;;oJAsBMA,YAAc,6FAKA,KAEhBA,YAAYC,gBAAgBC,iBAAiB,SAAUC,yBAGvDA,iCAMSA,wBAA0B,WAE7BC,iBAA6C,IAD5BJ,YAAYK,oBACKC,OAGlCC,2BAA6B,iBACZH,kCACCA,kBAIxBI,OAAOC,QAAQF,4BAA4BG,KAAIC,WAAEC,SAAUC,qBAAaC,kBAAkBF,SAAUC,4EAQ3FC,kBAAoB,CAACC,aAAcF,iBACtCG,QAAUC,SAASC,eAAeH,cAEnCC,UAMAH,QAGDG,QAAQG,gBAAgB,YAFxBH,QAAQI,aAAa,WAAY"}

group/amd/src/comboboxsearch/group.js

@@ -0,0 +1,227 @@
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Allow the user to search for groups.
+ *
+ * @module    core_group/comboboxsearch/group
+ * @copyright 2023 Mathew May <mathew.solutions>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+import search_combobox from 'core/comboboxsearch/search_combobox';
+import {groupFetch} from 'core_group/comboboxsearch/repository';
+import {renderForPromise, replaceNodeContents} from 'core/templates';
+import {debounce} from 'core/utils';
+import Notification from 'core/notification';
+
+export default class GroupSearch extends search_combobox {
+
+    courseID;
+    bannedFilterFields = ['id', 'link', 'groupimageurl'];
+
+    constructor() {
+        super();
+        this.selectors = {...this.selectors,
+            courseid: '[data-region="courseid"]',
+            placeholder: '.groupsearchdropdown [data-region="searchplaceholder"]',
+        };
+        const component = document.querySelector(this.componentSelector());
+        this.courseID = component.querySelector(this.selectors.courseid).dataset.courseid;
+        // Override the instance since the body is built outside the constructor for the combobox.
+        this.instance = component.querySelector(this.selectors.instance).dataset.instance;
+
+        const searchValueElement = this.component.querySelector(`#${this.searchInput.dataset.inputElement}`);
+        searchValueElement.addEventListener('change', () => {
+            this.toggleDropdown(); // Otherwise the dropdown stays open when user choose an option using keyboard.
+
+            const valueElement = this.component.querySelector(`#${this.combobox.dataset.inputElement}`);
+            if (valueElement.value !== searchValueElement.value) {
+                valueElement.value = searchValueElement.value;
+                valueElement.dispatchEvent(new Event('change', {bubbles: true}));
+            }
+
+            searchValueElement.value = '';
+        });
+
+        this.$component.on('hide.bs.dropdown', () => {
+            this.searchInput.removeAttribute('aria-activedescendant');
+
+            const listbox = document.querySelector(`#${this.searchInput.getAttribute('aria-controls')}[role="listbox"]`);
+            listbox.querySelectorAll('.active[role="option"]').forEach(option => {
+                option.classList.remove('active');
+            });
+            listbox.scrollTop = 0;
+
+            // Use setTimeout to make sure the following code is executed after the click event is handled.
+            setTimeout(() => {
+                if (this.searchInput.value !== '') {
+                    this.searchInput.value = '';
+                    this.searchInput.dispatchEvent(new Event('input', {bubbles: true}));
+                }
+            });
+        });
+
+        this.renderDefault().catch(Notification.exception);
+    }
+
+    static init() {
+        return new GroupSearch();
+    }
+
+    /**
+     * The overall div that contains the searching widget.
+     *
+     * @returns {string}
+     */
+    componentSelector() {
+        return '.group-search';
+    }
+
+    /**
+     * The dropdown div that contains the searching widget result space.
+     *
+     * @returns {string}
+     */
+    dropdownSelector() {
+        return '.groupsearchdropdown';
+    }
+
+    /**
+     * Build the content then replace the node.
+     */
+    async renderDropdown() {
+        const {html, js} = await renderForPromise('core_group/comboboxsearch/resultset', {
+            groups: this.getMatchedResults(),
+            hasresults: this.getMatchedResults().length > 0,
+            instance: this.instance,
+            searchterm: this.getSearchTerm(),
+        });
+        replaceNodeContents(this.selectors.placeholder, html, js);
+        // Remove aria-activedescendant when the available options change.
+        this.searchInput.removeAttribute('aria-activedescendant');
+    }
+
+    /**
+     * Build the content then replace the node by default we want our form to exist.
+     */
+    async renderDefault() {
+        this.setMatchedResults(await this.filterDataset(await this.getDataset()));
+        this.filterMatchDataset();
+
+        await this.renderDropdown();
+
+        this.updateNodes();
+    }
+
+    /**
+     * Get the data we will be searching against in this component.
+     *
+     * @returns {Promise<*>}
+     */
+    async fetchDataset() {
+        return await groupFetch(this.courseID).then((r) => r.groups);
+    }
+
+    /**
+     * Dictate to the search component how and what we want to match upon.
+     *
+     * @param {Array} filterableData
+     * @returns {Array} The users that match the given criteria.
+     */
+    async filterDataset(filterableData) {
+        // Sometimes we just want to show everything.
+        if (this.getPreppedSearchTerm() === '') {
+            return filterableData;
+        }
+        return filterableData.filter((group) => Object.keys(group).some((key) => {
+            if (group[key] === "" || this.bannedFilterFields.includes(key)) {
+                return false;
+            }
+            return group[key].toString().toLowerCase().includes(this.getPreppedSearchTerm());
+        }));
+    }
+
+    /**
+     * Given we have a subset of the dataset, set the field that we matched upon to inform the end user.
+     */
+    filterMatchDataset() {
+        this.setMatchedResults(
+            this.getMatchedResults().map((group) => {
+                return {
+                    id: group.id,
+                    name: group.name,
+                    groupimageurl: group.groupimageurl,
+                };
+            })
+        );
+    }
+
+    /**
+     * The handler for when a user interacts with the component.
+     *
+     * @param {MouseEvent} e The triggering event that we are working with.
+     */
+    async clickHandler(e) {
+        if (e.target.closest(this.selectors.clearSearch)) {
+            e.stopPropagation();
+            // Clear the entered search query in the search bar.
+            this.searchInput.value = '';
+            this.setSearchTerms(this.searchInput.value);
+            this.searchInput.focus();
+            this.clearSearchButton.classList.add('d-none');
+            // Display results.
+            await this.filterrenderpipe();
+        }
+    }
+
+    /**
+     * The handler for when a user changes the value of the component (selects an option from the dropdown).
+     *
+     * @param {Event} e The change event.
+     */
+    changeHandler(e) {
+        window.location = this.selectOneLink(e.target.value);
+    }
+
+    /**
+     * Override the input event listener for the text input area.
+     */
+    registerInputHandlers() {
+        // Register & handle the text input.
+        this.searchInput.addEventListener('input', debounce(async() => {
+            this.setSearchTerms(this.searchInput.value);
+            // We can also require a set amount of input before search.
+            if (this.getSearchTerm() === '') {
+                // Hide the "clear" search button in the search bar.
+                this.clearSearchButton.classList.add('d-none');
+            } else {
+                // Display the "clear" search button in the search bar.
+                this.clearSearchButton.classList.remove('d-none');
+            }
+            // User has given something for us to filter against.
+            await this.filterrenderpipe();
+        }, 300));
+    }
+
+    /**
+     * Build up the view all link that is dedicated to a particular result.
+     * We will call this function when a user interacts with the combobox to redirect them to show their results in the page.
+     *
+     * @param {Number} groupID The ID of the group selected.
+     */
+    selectOneLink(groupID) {
+        throw new Error(`selectOneLink(${groupID}) must be implemented in ${this.constructor.name}`);
+    }
+}

group/amd/src/comboboxsearch/repository.js

@@ -0,0 +1,41 @@
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * A repo for the comboboxsearch group type.
+ *
+ * @module    core_group/comboboxsearch/repository
+ * @copyright 2023 Mathew May <mathew.solutions>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+import ajax from "core/ajax";
+
+/**
+ * Given a course ID, we want to fetch the groups, so we may fetch their users.
+ *
+ * @method groupFetch
+ * @param {int} courseid ID of the course to fetch the users of.
+ * @return {object} jQuery promise
+ */
+export const groupFetch = (courseid) => {
+    const request = {
+        methodname: 'core_group_get_groups_for_selector',
+        args: {
+            courseid: courseid,
+        },
+    };
+    return ajax.call([request])[0];
+};

group/amd/src/grouppicker.js

@@ -0,0 +1,63 @@
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+/**
+ * @module     core_group/groupPicker
+ * @copyright  2022 Matthew Hilton <matthewhilton@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+/**
+ * Class used for interfacing with the group select picker.
+ *
+ * @class core_group/GroupPicker
+ */
+export default class GroupPicker {
+    /**
+     * Creates the group picker class and finds the corresponding DOM element.
+     *
+     * @param {String} elementId The DOM element id of the <select> input
+     * @throws Error if the element was not found.
+     */
+    constructor(elementId = "groups") {
+        const pickerDomElement = document.getElementById(elementId);
+
+        if (!pickerDomElement) {
+            throw new Error("Groups picker was not found.");
+        }
+
+        this.element = pickerDomElement;
+    }
+
+    /**
+     * Returns the DOM element this class is linked to.
+     *
+     * @returns {HTMLElement} The DOM element
+     */
+    getDomElement() {
+        return this.element;
+    }
+
+    /**
+     * Returns the selected group values.
+     *
+     * @returns {Number[]} The group IDs that are currently selected.
+     */
+    getSelectedValues() {
+        const selectedOptionElements = Array.from(this.element.querySelectorAll("option:checked"));
+        const selectedGroups = selectedOptionElements.map(el => parseInt(el.value));
+
+        return selectedGroups;
+    }
+}

group/amd/src/index.js

@@ -0,0 +1,72 @@
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+/**
+ * @module     core_group/index
+ * @copyright  2022 Matthew Hilton <matthewhilton@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+import GroupPicker from "./grouppicker";
+
+const groupPicker = new GroupPicker();
+
+/**
+ * Initialise page.
+ */
+export const init = () => {
+    // Init event listeners.
+    groupPicker.getDomElement().addEventListener("change", updateBulkActionButtons);
+
+    // Call initially to set initial button state.
+    updateBulkActionButtons();
+};
+
+/**
+ * Updates the bulk action buttons depending on specific conditions.
+ */
+export const updateBulkActionButtons = () => {
+    const groupsSelected = groupPicker.getSelectedValues();
+    const aGroupIsSelected = groupsSelected.length !== 0;
+
+    // Collate the conditions where each button is enabled/disabled.
+    const bulkActionsEnabledStatuses = {
+        'enablemessaging': aGroupIsSelected,
+        'disablemessaging': aGroupIsSelected
+    };
+
+    // Update the status of each button.
+    Object.entries(bulkActionsEnabledStatuses).map(([buttonId, enabled]) => setElementEnabled(buttonId, enabled));
+};
+
+/**
+ * Adds or removes the given element's disabled attribute.
+ * @param {string} domElementId ID of the dom element (without the #)
+ * @param {bool} enabled If false, the disable attribute is applied, else it is removed.
+ */
+export const setElementEnabled = (domElementId, enabled) => {
+    const element = document.getElementById(domElementId);
+
+    if (!element) {
+        // If there is no element, we do nothing.
+        // The element could be purposefully hidden or removed.
+        return;
+    }
+
+    if (!enabled) {
+        element.setAttribute('disabled', 'disabled');
+    } else {
+        element.removeAttribute('disabled');
+    }
+};

group/assign.php

@@ -0,0 +1,193 @@
+<?php
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Add/remove group from grouping.
+ *
+ * @copyright 1999 Martin Dougiamas  http://dougiamas.com
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+
+require_once('../config.php');
+require_once('lib.php');
+
+$groupingid = required_param('id', PARAM_INT);
+
+$PAGE->set_url('/group/assign.php', array('id'=>$groupingid));
+
+if (!$grouping = $DB->get_record('groupings', array('id'=>$groupingid))) {
+    throw new \moodle_exception('invalidgroupid');
+}
+
+if (!$course = $DB->get_record('course', array('id'=>$grouping->courseid))) {
+    throw new \moodle_exception('invalidcourse');
+}
+$courseid = $course->id;
+
+require_login($course);
+$context = context_course::instance($courseid);
+require_capability('moodle/course:managegroups', $context);
+
+$returnurl = $CFG->wwwroot.'/group/groupings.php?id='.$courseid;
+
+
+if ($frm = data_submitted() and confirm_sesskey()) {
+
+    if (isset($frm->cancel)) {
+        redirect($returnurl);
+
+    } else if (isset($frm->add) and !empty($frm->addselect)) {
+        foreach ($frm->addselect as $groupid) {
+            // Ask this method not to purge the cache, we'll do it ourselves afterwards.
+            groups_assign_grouping($grouping->id, (int)$groupid, null, false);
+        }
+        // Invalidate the course groups cache seeing as we've changed it.
+        cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
+
+        // Invalidate the user_group_groupings cache, too.
+        cache_helper::purge_by_definition('core', 'user_group_groupings');
+    } else if (isset($frm->remove) and !empty($frm->removeselect)) {
+        foreach ($frm->removeselect as $groupid) {
+            // Ask this method not to purge the cache, we'll do it ourselves afterwards.
+            groups_unassign_grouping($grouping->id, (int)$groupid, false);
+        }
+        // Invalidate the course groups cache seeing as we've changed it.
+        cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
+
+        // Invalidate the user_group_groupings cache, too.
+        cache_helper::purge_by_definition('core', 'user_group_groupings');
+    }
+}
+
+
+$currentmembers = array();
+$potentialmembers  = array();
+
+if ($groups = $DB->get_records('groups', array('courseid'=>$courseid), 'name')) {
+    if ($assignment = $DB->get_records('groupings_groups', array('groupingid'=>$grouping->id))) {
+        foreach ($assignment as $ass) {
+            $currentmembers[$ass->groupid] = $groups[$ass->groupid];
+            unset($groups[$ass->groupid]);
+        }
+    }
+    $potentialmembers = $groups;
+}
+
+$currentmembersoptions = '';
+$currentmemberscount = 0;
+if ($currentmembers) {
+    foreach($currentmembers as $group) {
+        $currentmembersoptions .= '<option value="' . $group->id . '." title="' . format_string($group->name) . '">' .
+                format_string($group->name) . '</option>';
+        $currentmemberscount ++;
+    }
+
+    // Get course managers so they can be highlighted in the list
+    if ($managerroles = get_config('', 'coursecontact')) {
+        $coursecontactroles = explode(',', $managerroles);
+        foreach ($coursecontactroles as $roleid) {
+            $role = $DB->get_record('role', array('id'=>$roleid));
+            $managers = get_role_users($roleid, $context, true, 'u.id', 'u.id ASC');
+        }
+    }
+} else {
+    $currentmembersoptions .= '<option>&nbsp;</option>';
+}
+
+$potentialmembersoptions = '';
+$potentialmemberscount = 0;
+if ($potentialmembers) {
+    foreach($potentialmembers as $group) {
+        $potentialmembersoptions .= '<option value="' . $group->id . '." title="' . format_string($group->name) . '">' .
+                format_string($group->name) . '</option>';
+        $potentialmemberscount ++;
+    }
+} else {
+    $potentialmembersoptions .= '<option>&nbsp;</option>';
+}
+
+// Print the page and form
+$strgroups = get_string('groups');
+$strparticipants = get_string('participants');
+$straddgroupstogroupings = get_string('addgroupstogroupings', 'group');
+
+$groupingname = format_string($grouping->name);
+
+navigation_node::override_active_url(new moodle_url('/group/index.php', array('id'=>$course->id)));
+$PAGE->set_pagelayout('admin');
+
+$PAGE->navbar->add($strparticipants, new moodle_url('/user/index.php', array('id'=>$courseid)));
+$PAGE->navbar->add(get_string('groupings', 'group'),
+    new moodle_url('/group/groupings.php', ['id' => $courseid]));
+$PAGE->navbar->add($straddgroupstogroupings);
+
+/// Print header
+$PAGE->set_title("$course->shortname: $strgroups");
+$PAGE->set_heading($course->fullname);
+echo $OUTPUT->header();
+
+?>
+<div id="addmembersform">
+    <h3 class="main"><?php print_string('addgroupstogroupings', 'group'); echo ": $groupingname"; ?></h3>
+    <form id="assignform" method="post" action="">
+    <div>
+    <input type="hidden" name="sesskey" value="<?php p(sesskey()); ?>" />
+    <table summary="" class="generaltable generalbox groupmanagementtable boxaligncenter">
+    <tr>
+      <td id="existingcell">
+          <label for="removeselect"><?php print_string('existingmembers', 'group', $currentmemberscount); ?></label>
+          <div class="userselector" id="removeselect_wrapper">
+          <select name="removeselect[]" size="20" id="removeselect" multiple="multiple"
+                  onfocus="document.getElementById('assignform').add.disabled=true;
+                           document.getElementById('assignform').remove.disabled=false;
+                           document.getElementById('assignform').addselect.selectedIndex=-1;">
+          <?php echo $currentmembersoptions ?>
+          </select></div></td>
+      <td id="buttonscell">
+        <p class="arrow_button">
+            <input class="btn btn-secondary" name="add" id="add" type="submit"
+                   value="<?php echo $OUTPUT->larrow().'&nbsp;'.get_string('add'); ?>"
+                   title="<?php print_string('add'); ?>" /><br>
+            <input class="btn btn-secondary" name="remove" id="remove" type="submit"
+                   value="<?php echo get_string('remove').'&nbsp;'.$OUTPUT->rarrow(); ?>"
+                   title="<?php print_string('remove'); ?>" />
+        </p>
+      </td>
+      <td id="potentialcell">
+          <label for="addselect"><?php print_string('potentialmembers', 'group', $potentialmemberscount); ?></label>
+          <div class="userselector" id="addselect_wrapper">
+          <select name="addselect[]" size="20" id="addselect" multiple="multiple"
+                  onfocus="document.getElementById('assignform').add.disabled=false;
+                           document.getElementById('assignform').remove.disabled=true;
+                           document.getElementById('assignform').removeselect.selectedIndex=-1;">
+         <?php echo $potentialmembersoptions ?>
+         </select>
+          </div>
+       </td>
+    </tr>
+    <tr><td colspan="3" id="backcell">
+        <input class="btn btn-secondary" type="submit" name="cancel"
+               value="<?php print_string('backtogroupings', 'group'); ?>" />
+    </td></tr>
+    </table>
+    </div>
+    </form>
+</div>
+
+<?php
+    echo $OUTPUT->footer();

group/autogroup.php

@@ -0,0 +1,285 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * Create and allocate users to groups
+ *
+ * @package    core_group
+ * @copyright  Matt Clarkson mattc@catalyst.net.nz
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+require_once('../config.php');
+require_once('lib.php');
+require_once('autogroup_form.php');
+
+if (!defined('AUTOGROUP_MIN_RATIO')) {
+    define('AUTOGROUP_MIN_RATIO', 0.7); // means minimum member count is 70% in the smallest group
+}
+
+$courseid = required_param('courseid', PARAM_INT);
+$PAGE->set_url('/group/autogroup.php', array('courseid' => $courseid));
+
+if (!$course = $DB->get_record('course', array('id'=>$courseid))) {
+    throw new \moodle_exception('invalidcourseid');
+}
+
+// Make sure that the user has permissions to manage groups.
+require_login($course);
+
+$context       = context_course::instance($courseid);
+require_capability('moodle/course:managegroups', $context);
+
+$returnurl = $CFG->wwwroot.'/group/index.php?id='.$course->id;
+
+$strgroups           = get_string('groups');
+$strparticipants     = get_string('participants');
+$strautocreategroups = get_string('autocreategroups', 'group');
+
+$PAGE->set_title($strgroups);
+$PAGE->set_heading($course->fullname. ': '.$strgroups);
+$PAGE->set_pagelayout('admin');
+navigation_node::override_active_url(new moodle_url('/group/index.php', array('id' => $courseid)));
+
+// Print the page and form
+$preview = '';
+$error = '';
+
+/// Get applicable roles - used in menus etc later on
+$rolenames = role_fix_names(get_profile_roles($context), $context, ROLENAME_BOTH, true);
+
+/// Create the form
+$editform = new autogroup_form(null, array('roles' => $rolenames));
+$editform->set_data(array('courseid' => $courseid, 'seed' => time()));
+
+/// Handle form submission
+if ($editform->is_cancelled()) {
+    redirect($returnurl);
+
+} elseif ($data = $editform->get_data()) {
+
+    /// Allocate members from the selected role to groups
+    switch ($data->allocateby) {
+        case 'no':
+        case 'random':
+        case 'lastname':
+            $orderby = 'lastname, firstname'; break;
+        case 'firstname':
+            $orderby = 'firstname, lastname'; break;
+        case 'idnumber':
+            $orderby = 'idnumber'; break;
+        default:
+            throw new \moodle_exception('unknoworder');
+    }
+    $source = array();
+    if ($data->cohortid) {
+        $source['cohortid'] = $data->cohortid;
+    }
+    if ($data->groupingid) {
+        $source['groupingid'] = $data->groupingid;
+    }
+    if ($data->groupid) {
+        $source['groupid'] = $data->groupid;
+    }
+
+    // Display only active users if the option was selected or they do not have the capability to view suspended users.
+    $onlyactive = !empty($data->includeonlyactiveenrol) || !has_capability('moodle/course:viewsuspendedusers', $context);
+
+    // TODO Does not support custom user profile fields (MDL-70456).
+    $extrafields = \core_user\fields::get_identity_fields($context, false);
+    $users = groups_get_potential_members($data->courseid, $data->roleid, $source, $orderby, !empty($data->notingroup),
+        $onlyactive, $extrafields);
+    $usercnt = count($users);
+
+    if ($data->allocateby == 'random') {
+        srand($data->seed);
+        shuffle($users);
+    }
+
+    $groups = array();
+
+    // Plan the allocation
+    if ($data->groupby == 'groups') {
+        $numgrps    = $data->number;
+        $userpergrp = floor($usercnt/$numgrps);
+
+    } else { // members
+        $numgrps    = ceil($usercnt/$data->number);
+        $userpergrp = $data->number;
+
+        if (!empty($data->nosmallgroups) and $usercnt % $data->number != 0) {
+            // If there would be one group with a small number of member reduce the number of groups
+            $missing = $userpergrp * $numgrps - $usercnt;
+            if ($missing > $userpergrp * (1-AUTOGROUP_MIN_RATIO)) {
+                // spread the users from the last small group
+                $numgrps--;
+                $userpergrp = floor($usercnt/$numgrps);
+            }
+        }
+    }
+
+    // allocate the users - all groups equal count first
+    for ($i=0; $i<$numgrps; $i++) {
+        $groups[$i] = array();
+        $groups[$i]['name']    = groups_parse_name(trim($data->namingscheme), $i);
+        $groups[$i]['members'] = array();
+        if ($data->allocateby == 'no') {
+            continue; // do not allocate users
+        }
+        for ($j=0; $j<$userpergrp; $j++) {
+            if (empty($users)) {
+                break 2;
+            }
+            $user = array_shift($users);
+            $groups[$i]['members'][$user->id] = $user;
+        }
+    }
+    // now distribute the rest
+    if ($data->allocateby != 'no') {
+        for ($i=0; $i<$numgrps; $i++) {
+            if (empty($users)) {
+                break 1;
+            }
+            $user = array_shift($users);
+            $groups[$i]['members'][$user->id] = $user;
+        }
+    }
+
+    if (isset($data->preview)) {
+        $table = new html_table();
+        if ($data->allocateby == 'no') {
+            $table->head  = array(get_string('groupscount', 'group', $numgrps));
+            $table->size  = array('100%');
+            $table->align = array('left');
+            $table->width = '40%';
+        } else {
+            $table->head  = array(get_string('groupscount', 'group', $numgrps), get_string('groupmembers', 'group'), get_string('usercounttotal', 'group', $usercnt));
+            $table->size  = array('20%', '70%', '10%');
+            $table->align = array('left', 'left', 'center');
+            $table->width = '90%';
+        }
+        $table->data  = array();
+        $viewfullnames = has_capability('moodle/site:viewfullnames', $context);
+        foreach ($groups as $group) {
+            $line = array();
+            if (groups_get_group_by_name($courseid, $group['name'])) {
+                $line[] = '<span class="notifyproblem">'.get_string('groupnameexists', 'group', $group['name']).'</span>';
+                $error = get_string('groupnameexists', 'group', $group['name']);
+            } else {
+                $line[] = $group['name'];
+            }
+            if ($data->allocateby != 'no') {
+                $unames = array();
+                foreach ($group['members'] as $user) {
+                    $fullname = fullname($user, $viewfullnames);
+                    if ($extrafields) {
+                        $extrafieldsdisplay = [];
+                        foreach ($extrafields as $field) {
+                            $extrafieldsdisplay[] = s($user->{$field});
+                        }
+                        $fullname .= ' (' . implode(', ', $extrafieldsdisplay) . ')';
+                    }
+
+                    $unames[] = $fullname;
+                }
+                $line[] = implode(', ', $unames);
+                $line[] = count($group['members']);
+            }
+            $table->data[] = $line;
+        }
+
+        $preview .= html_writer::table($table);
+
+    } else {
+        $grouping = null;
+        $createdgrouping = null;
+        $createdgroups = array();
+        $failed = false;
+
+        // prepare grouping
+        if (!empty($data->grouping)) {
+            if ($data->grouping < 0) {
+                $grouping = new stdClass();
+                $grouping->courseid = $COURSE->id;
+                $grouping->name     = trim($data->groupingname);
+                $grouping->id = groups_create_grouping($grouping);
+                $createdgrouping = $grouping->id;
+            } else {
+                $grouping = groups_get_grouping($data->grouping);
+            }
+        }
+
+        // Save the groups data
+        foreach ($groups as $key=>$group) {
+            if (groups_get_group_by_name($courseid, $group['name'])) {
+                $error = get_string('groupnameexists', 'group', $group['name']);
+                $failed = true;
+                break;
+            }
+            $newgroup = new stdClass();
+            $newgroup->courseid = $data->courseid;
+            $newgroup->name     = $group['name'];
+            $newgroup->enablemessaging = $data->enablemessaging ?? 0;
+            $newgroup->visibility = GROUPS_VISIBILITY_ALL;
+            $groupid = groups_create_group($newgroup);
+            $createdgroups[] = $groupid;
+            foreach($group['members'] as $user) {
+                groups_add_member($groupid, $user->id);
+            }
+            if ($grouping) {
+                // Ask this function not to invalidate the cache, we'll do that manually once at the end.
+                groups_assign_grouping($grouping->id, $groupid, null, false);
+            }
+        }
+
+        // Invalidate the course groups cache seeing as we've changed it.
+        cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
+
+        if ($failed) {
+            foreach ($createdgroups as $groupid) {
+                groups_delete_group($groupid);
+            }
+            if ($createdgrouping) {
+                groups_delete_grouping($createdgrouping);
+            }
+        } else {
+            redirect($returnurl);
+        }
+    }
+}
+
+$PAGE->navbar->add($strparticipants, new moodle_url('/user/index.php', array('id'=>$courseid)));
+$PAGE->navbar->add($strgroups, new moodle_url('/group/index.php', array('id'=>$courseid)));
+$PAGE->navbar->add($strautocreategroups);
+
+echo $OUTPUT->header();
+echo $OUTPUT->heading($strautocreategroups);
+
+if ($error != '') {
+    echo $OUTPUT->notification($error);
+}
+
+/// Display the form
+$editform->display();
+
+if($preview !== '') {
+    echo $OUTPUT->heading(get_string('groupspreview', 'group'));
+
+    echo $preview;
+}
+
+echo $OUTPUT->footer();

group/autogroup_form.php

@@ -0,0 +1,255 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * Auto group form
+ *
+ * @package    core_group
+ * @copyright  2007 mattc-catalyst (http://moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+if (!defined('MOODLE_INTERNAL')) {
+    die('Direct access to this script is forbidden.');    ///  It must be included from a Moodle page
+}
+
+require_once($CFG->dirroot.'/lib/formslib.php');
+require_once($CFG->dirroot.'/cohort/lib.php');
+
+/**
+ * Auto group form class
+ *
+ * @package    core_group
+ * @copyright  2007 mattc-catalyst (http://moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class autogroup_form extends moodleform {
+
+    /**
+     * Form Definition
+     */
+    function definition() {
+        global $USER, $COURSE;
+        $coursecontext = context_course::instance($COURSE->id);
+
+        $mform =& $this->_form;
+
+        $mform->addElement('header', 'autogroup', get_string('general'));
+
+        $mform->addElement('text', 'namingscheme', get_string('namingscheme', 'group'));
+        $mform->addHelpButton('namingscheme', 'namingscheme', 'group');
+        $mform->addRule('namingscheme', get_string('required'), 'required', null, 'client');
+        $mform->setType('namingscheme', PARAM_TEXT);
+        // There must not be duplicate group names in course.
+        $template = get_string('grouptemplate', 'group');
+        $gname = groups_parse_name($template, 0);
+        if (!groups_get_group_by_name($COURSE->id, $gname)) {
+            $mform->setDefault('namingscheme', $template);
+        }
+
+        $options = array('groups' => get_string('numgroups', 'group'),
+                         'members' => get_string('nummembers', 'group'));
+        $mform->addElement('select', 'groupby', get_string('groupby', 'group'), $options);
+
+        $mform->addElement('text', 'number', get_string('number', 'group'),'maxlength="4" size="4"');
+        $mform->setType('number', PARAM_INT);
+        $mform->addRule('number', null, 'numeric', null, 'client');
+        $mform->addRule('number', get_string('required'), 'required', null, 'client');
+
+        // Enable group messaging for the groups to be auto-created.
+        if (\core_message\api::can_create_group_conversation($USER->id, $coursecontext)) {
+            $mform->addElement('selectyesno', 'enablemessaging', get_string('enablemessaging', 'group'));
+            $mform->addHelpButton('enablemessaging', 'enablemessaging', 'group');
+        }
+
+        $mform->addElement('header', 'groupmembershdr', get_string('groupmembers', 'group'));
+        $mform->setExpanded('groupmembershdr', true);
+
+        $options = array(0=>get_string('all'));
+        $options += $this->_customdata['roles'];
+        $mform->addElement('select', 'roleid', get_string('selectfromrole', 'group'), $options);
+
+        $student = get_archetype_roles('student');
+        $student = reset($student);
+
+        if ($student and array_key_exists($student->id, $options)) {
+            $mform->setDefault('roleid', $student->id);
+        }
+
+        $coursecontext = context_course::instance($COURSE->id);
+        if ($cohorts = cohort_get_available_cohorts($coursecontext, COHORT_WITH_ENROLLED_MEMBERS_ONLY, 0, 0)) {
+            $options = array(0 => get_string('anycohort', 'cohort'));
+            foreach ($cohorts as $c) {
+                $options[$c->id] = format_string($c->name, true, [
+                    'context' => context::instance_by_id($c->contextid),
+                ]);
+            }
+            $mform->addElement('select', 'cohortid', get_string('selectfromcohort', 'cohort'), $options);
+            $mform->setDefault('cohortid', '0');
+        } else {
+            $mform->addElement('hidden','cohortid');
+            $mform->setType('cohortid', PARAM_INT);
+            $mform->setConstant('cohortid', '0');
+        }
+
+        if ($groupings = groups_get_all_groupings($COURSE->id)) {
+            $options = array();
+            $options[0] = get_string('none');
+            foreach ($groupings as $grouping) {
+                $options[$grouping->id] = format_string($grouping->name);
+            }
+            $mform->addElement('select', 'groupingid', get_string('selectfromgrouping', 'group'), $options);
+            $mform->setDefault('groupingid', 0);
+            $mform->disabledIf('groupingid', 'notingroup', 'checked');
+        } else {
+            $mform->addElement('hidden', 'groupingid');
+            $mform->setType('groupingid', PARAM_INT);
+            $mform->setConstant('groupingid', 0);
+        }
+
+        if ($groups = groups_get_all_groups($COURSE->id)) {
+            $options = array();
+            $options[0] = get_string('none');
+            foreach ($groups as $group) {
+                $options[$group->id] = format_string($group->name);
+            }
+            $mform->addElement('select', 'groupid', get_string('selectfromgroup', 'group'), $options);
+            $mform->setDefault('groupid', 0);
+            $mform->disabledIf('groupid', 'notingroup', 'checked');
+        } else {
+            $mform->addElement('hidden', 'groupid');
+            $mform->setType('groupid', PARAM_INT);
+            $mform->setConstant('groupid', 0);
+        }
+
+        $options = array('no'        => get_string('noallocation', 'group'),
+                         'random'    => get_string('random', 'group'),
+                         'firstname' => get_string('byfirstname', 'group'),
+                         'lastname'  => get_string('bylastname', 'group'),
+                         'idnumber'  => get_string('byidnumber', 'group'));
+        $mform->addElement('select', 'allocateby', get_string('allocateby', 'group'), $options);
+        $mform->setDefault('allocateby', 'random');
+
+        $mform->addElement('checkbox', 'nosmallgroups', get_string('nosmallgroups', 'group'));
+        $mform->disabledIf('nosmallgroups', 'groupby', 'noteq', 'members');
+
+        $mform->addElement('checkbox', 'notingroup', get_string('notingroup', 'group'));
+        $mform->disabledIf('notingroup', 'groupingid', 'neq', 0);
+        $mform->disabledIf('notingroup', 'groupid', 'neq', 0);
+
+        if (has_capability('moodle/course:viewsuspendedusers', $coursecontext)) {
+            $mform->addElement('checkbox', 'includeonlyactiveenrol', get_string('includeonlyactiveenrol', 'group'), '');
+            $mform->addHelpButton('includeonlyactiveenrol', 'includeonlyactiveenrol', 'group');
+            $mform->setDefault('includeonlyactiveenrol', true);
+        }
+
+        $mform->addElement('header', 'groupinghdr', get_string('grouping', 'group'));
+
+        $options = array('0' => get_string('nogrouping', 'group'),
+                         '-1'=> get_string('newgrouping', 'group'));
+        if ($groupings = groups_get_all_groupings($COURSE->id)) {
+            foreach ($groupings as $grouping) {
+                $options[$grouping->id] = strip_tags(format_string($grouping->name));
+            }
+        }
+        $mform->addElement('select', 'grouping', get_string('createingrouping', 'group'), $options);
+        if ($groupings) {
+            $mform->setDefault('grouping', '-1');
+        }
+
+        $mform->addElement('text', 'groupingname', get_string('groupingname', 'group'), $options);
+        $mform->setType('groupingname', PARAM_TEXT);
+        $mform->disabledIf('groupingname', 'grouping', 'noteq', '-1');
+
+        $mform->addElement('hidden','courseid');
+        $mform->setType('courseid', PARAM_INT);
+
+        $mform->addElement('hidden','seed');
+        $mform->setType('seed', PARAM_INT);
+
+        $buttonarray = array();
+        $buttonarray[] = &$mform->createElement('submit', 'preview', get_string('preview'));
+        $buttonarray[] = &$mform->createElement('submit', 'submitbutton', get_string('submit'));
+        $buttonarray[] = &$mform->createElement('cancel');
+        $mform->addGroup($buttonarray, 'buttonar', '', array(' '), false);
+        $mform->closeHeaderBefore('buttonar');
+    }
+
+    /**
+     * Performs validation of the form information
+     *
+     * @param array $data
+     * @param array $files
+     * @return array $errors An array of $errors
+     */
+    function validation($data, $files) {
+        global $CFG, $COURSE;
+        $errors = parent::validation($data, $files);
+
+        if ($data['allocateby'] != 'no') {
+            $source = array();
+            if ($data['cohortid']) {
+                $source['cohortid'] = $data['cohortid'];
+            }
+            if ($data['groupingid']) {
+                $source['groupingid'] = $data['groupingid'];
+            }
+            if ($data['groupid']) {
+                $source['groupid'] = $data['groupid'];
+            }
+            if (!$users = groups_get_potential_members($data['courseid'], $data['roleid'], $source)) {
+                $errors['roleid'] = get_string('nousersinrole', 'group');
+            }
+
+           /// Check the number entered is sane
+            if ($data['groupby'] == 'groups') {
+                $usercnt = count($users);
+
+                if ($data['number'] > $usercnt || $data['number'] < 1) {
+                    $errors['number'] = get_string('toomanygroups', 'group', $usercnt);
+                }
+            }
+        }
+
+        //try to detect group name duplicates
+        $name = groups_parse_name(trim($data['namingscheme']), 0);
+        if (groups_get_group_by_name($COURSE->id, $name)) {
+            $errors['namingscheme'] = get_string('groupnameexists', 'group', $name);
+        }
+
+        // check grouping name duplicates
+        if ( isset($data['grouping']) && $data['grouping'] == '-1') {
+            $name = trim($data['groupingname']);
+            if (empty($name)) {
+                $errors['groupingname'] = get_string('required');
+            } else if (groups_get_grouping_by_name($COURSE->id, $name)) {
+                $errors['groupingname'] = get_string('groupingnameexists', 'group', $name);
+            }
+        }
+
+       /// Check the naming scheme
+        if ($data['groupby'] == 'groups' and $data['number'] == 1) {
+            // we can use the name as is because there will be only one group max
+        } else {
+            $matchcnt = preg_match_all('/[#@]{1,1}/', $data['namingscheme'], $matches);
+            if ($matchcnt != 1) {
+                $errors['namingscheme'] = get_string('badnamingscheme', 'group');
+            }
+        }
+
+        return $errors;
+    }
+}

group/classes/customfield/group_handler.php

@@ -0,0 +1,189 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\customfield;
+
+use context;
+use context_course;
+use context_system;
+use core_customfield\api;
+use core_customfield\handler;
+use core_customfield\field_controller;
+use moodle_url;
+use restore_task;
+
+/**
+ * Group handler for custom fields.
+ *
+ * @package   core_group
+ * @author    Tomo Tsuyuki <tomotsuyuki@catalyst-au.net>
+ * @copyright 2023 Catalyst IT Pty Ltd
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class group_handler extends handler {
+
+    /**
+     * @var group_handler
+     */
+    static protected $singleton;
+
+    /**
+     * Returns a singleton.
+     *
+     * @param int $itemid
+     * @return \core_customfield\handler
+     */
+    public static function create(int $itemid = 0): handler {
+        if (static::$singleton === null) {
+            self::$singleton = new static(0);
+        }
+        return self::$singleton;
+    }
+
+    /**
+     * Run reset code after unit tests to reset the singleton usage.
+     */
+    public static function reset_caches(): void {
+        if (!PHPUNIT_TEST) {
+            throw new \coding_exception('This feature is only intended for use in unit tests');
+        }
+
+        static::$singleton = null;
+    }
+
+    /**
+     * The current user can configure custom fields on this component.
+     *
+     * @return bool true if the current can configure custom fields, false otherwise
+     */
+    public function can_configure(): bool {
+        return has_capability('moodle/group:configurecustomfields', $this->get_configuration_context());
+    }
+
+    /**
+     * The current user can edit custom fields on the given group.
+     *
+     * @param field_controller $field
+     * @param int $instanceid id of the group to test edit permission
+     * @return bool true if the current can edit custom field, false otherwise
+     */
+    public function can_edit(field_controller $field, int $instanceid = 0): bool {
+        return has_capability('moodle/course:managegroups', $this->get_instance_context($instanceid));
+    }
+
+    /**
+     * The current user can view custom fields on the given group.
+     *
+     * @param field_controller $field
+     * @param int $instanceid id of the group to test edit permission
+     * @return bool true if the current can view custom field, false otherwise
+     */
+    public function can_view(field_controller $field, int $instanceid): bool {
+        return has_any_capability(['moodle/course:managegroups', 'moodle/course:view'], $this->get_instance_context($instanceid));
+    }
+
+    /**
+     * Context that should be used for new categories created by this handler.
+     *
+     * @return context the context for configuration
+     */
+    public function get_configuration_context(): context {
+        return context_system::instance();
+    }
+
+    /**
+     * URL for configuration of the fields on this handler.
+     *
+     * @return moodle_url The URL to configure custom fields for this component
+     */
+    public function get_configuration_url(): moodle_url {
+        return new moodle_url('/group/customfield.php');
+    }
+
+    /**
+     * Returns the context for the data associated with the given instanceid.
+     *
+     * @param int $instanceid id of the record to get the context for
+     * @return context the context for the given record
+     */
+    public function get_instance_context(int $instanceid = 0): \context {
+        global $COURSE, $DB;
+
+        if ($instanceid > 0) {
+            $group = $DB->get_record('groups', ['id' => $instanceid], '*', MUST_EXIST);
+            return context_course::instance($group->courseid);
+        } else if (!empty($COURSE->id)) {
+            return context_course::instance($COURSE->id);
+        } else {
+            return context_system::instance();
+        }
+    }
+
+    /**
+     * Get raw data associated with all fields current user can view or edit
+     *
+     * @param int $instanceid
+     * @return array
+     */
+    public function get_instance_data_for_backup(int $instanceid): array {
+        $finalfields = [];
+        $instancedata = $this->get_instance_data($instanceid, true);
+        foreach ($instancedata as $data) {
+            if ($data->get('id') && $this->can_backup($data->get_field(), $instanceid)) {
+                $finalfields[] = [
+                    'id' => $data->get('id'),
+                    'shortname' => $data->get_field()->get('shortname'),
+                    'type' => $data->get_field()->get('type'),
+                    'value' => $data->get_value(),
+                    'valueformat' => $data->get('valueformat'),
+                    'valuetrust' => $data->get('valuetrust'),
+                    'groupid' => $data->get('instanceid'),
+                ];
+            }
+        }
+        return $finalfields;
+    }
+
+    /**
+     * Creates or updates custom field data.
+     *
+     * @param restore_task $task
+     * @param array $data
+     *
+     * @return int|void Conditionally returns the ID of the created or updated record.
+     */
+    public function restore_instance_data_from_backup(restore_task $task, array $data) {
+        $instanceid = $data['groupid'];
+        $context = $this->get_instance_context($instanceid);
+        $editablefields = $this->get_editable_fields($instanceid);
+        $records = api::get_instance_fields_data($editablefields, $instanceid);
+
+        foreach ($records as $d) {
+            $field = $d->get_field();
+            if ($field->get('shortname') === $data['shortname'] && $field->get('type') === $data['type']) {
+                if (!$d->get('id')) {
+                    $d->set($d->datafield(), $data['value']);
+                    $d->set('value', $data['value']);
+                    $d->set('valueformat', $data['valueformat']);
+                    $d->set('valuetrust', !empty($data['valuetrust']));
+                    $d->set('contextid', $context->id);
+                    $d->save();
+                }
+                return $d->get('id');
+            }
+        }
+    }
+}

group/classes/customfield/grouping_handler.php

@@ -0,0 +1,190 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\customfield;
+
+use context;
+use context_course;
+use context_system;
+use core_customfield\api;
+use core_customfield\handler;
+use core_customfield\field_controller;
+use moodle_url;
+use restore_task;
+
+/**
+ * Grouping handler for custom fields.
+ *
+ * @package   core_group
+ * @author    Tomo Tsuyuki <tomotsuyuki@catalyst-au.net>
+ * @copyright 2023 Catalyst IT Pty Ltd
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class grouping_handler extends handler {
+
+    /**
+     * @var grouping_handler
+     */
+    static protected $singleton;
+
+    /**
+     * Returns a singleton.
+     *
+     * @param int $itemid
+     * @return \core_customfield\handler
+     */
+    public static function create(int $itemid = 0): handler {
+        if (static::$singleton === null) {
+            self::$singleton = new static(0);
+        }
+        return self::$singleton;
+    }
+
+    /**
+     * Run reset code after unit tests to reset the singleton usage.
+     */
+    public static function reset_caches(): void {
+        if (!PHPUNIT_TEST) {
+            throw new \coding_exception('This feature is only intended for use in unit tests');
+        }
+
+        static::$singleton = null;
+    }
+
+    /**
+     * The current user can configure custom fields on this component.
+     *
+     * @return bool true if the current can configure custom fields, false otherwise
+     */
+    public function can_configure(): bool {
+        return has_capability('moodle/group:configurecustomfields', $this->get_configuration_context());
+    }
+
+    /**
+     * The current user can edit custom fields on the given group.
+     *
+     * @param field_controller $field
+     * @param int $instanceid id of the group to test edit permission
+     * @return bool true if the current can edit custom field, false otherwise
+     */
+    public function can_edit(field_controller $field, int $instanceid = 0): bool {
+        return has_capability('moodle/course:managegroups', $this->get_instance_context($instanceid));
+    }
+
+    /**
+     * The current user can view custom fields on the given group.
+     *
+     * @param field_controller $field
+     * @param int $instanceid id of the group to test edit permission
+     * @return bool true if the current can view custom field, false otherwise
+     */
+    public function can_view(field_controller $field, int $instanceid): bool {
+        return has_any_capability(['moodle/course:managegroups', 'moodle/course:view'], $this->get_instance_context($instanceid));
+    }
+
+    /**
+     * Context that should be used for new categories created by this handler.
+     *
+     * @return context the context for configuration
+     */
+    public function get_configuration_context(): context {
+        return context_system::instance();
+    }
+
+    /**
+     * URL for configuration of the fields on this handler.
+     *
+     * @return moodle_url The URL to configure custom fields for this component
+     */
+    public function get_configuration_url(): moodle_url {
+        return new moodle_url('/group/grouping_customfield.php');
+    }
+
+    /**
+     * Returns the context for the data associated with the given instanceid.
+     *
+     * @param int $instanceid id of the record to get the context for
+     * @return context the context for the given record
+     */
+    public function get_instance_context(int $instanceid = 0): context {
+        global $COURSE, $DB;
+        if ($instanceid > 0) {
+            $grouping = $DB->get_record('groupings', ['id' => $instanceid], '*', MUST_EXIST);
+            return context_course::instance($grouping->courseid);
+        } else if (!empty($COURSE->id)) {
+            return context_course::instance($COURSE->id);
+        } else {
+            return context_system::instance();
+        }
+    }
+
+    /**
+     * Get raw data associated with all fields current user can view or edit
+     *
+     * @param int $instanceid
+     * @return array
+     */
+    public function get_instance_data_for_backup(int $instanceid): array {
+        $finalfields = [];
+        $instancedata = $this->get_instance_data($instanceid, true);
+        foreach ($instancedata as $data) {
+            if ($data->get('id') && $this->can_backup($data->get_field(), $instanceid)) {
+                $finalfields[] = [
+                    'id' => $data->get('id'),
+                    'shortname' => $data->get_field()->get('shortname'),
+                    'type' => $data->get_field()->get('type'),
+                    'value' => $data->get_value(),
+                    'valueformat' => $data->get('valueformat'),
+                    'valuetrust' => $data->get('valuetrust'),
+                    'groupingid' => $data->get('instanceid'),
+                ];
+            }
+        }
+        return $finalfields;
+    }
+
+    /**
+     * Creates or updates custom field data for a instanceid from backup data.
+     *
+     * The handlers have to override it if they support backup
+     *
+     * @param restore_task $task
+     * @param array $data
+     *
+     * @return int|void Conditionally returns the ID of the created or updated record.
+     */
+    public function restore_instance_data_from_backup(restore_task $task, array $data) {
+        $instanceid = $data['groupingid'];
+        $context = $this->get_instance_context($instanceid);
+        $editablefields = $this->get_editable_fields($instanceid);
+        $records = api::get_instance_fields_data($editablefields, $instanceid);
+
+        foreach ($records as $d) {
+            $field = $d->get_field();
+            if ($field->get('shortname') === $data['shortname'] && $field->get('type') === $data['type']) {
+                if (!$d->get('id')) {
+                    $d->set($d->datafield(), $data['value']);
+                    $d->set('value', $data['value']);
+                    $d->set('valueformat', $data['valueformat']);
+                    $d->set('valuetrust', !empty($data['valuetrust']));
+                    $d->set('contextid', $context->id);
+                    $d->save();
+                }
+                return $d->get('id');
+            }
+        }
+    }
+}

group/classes/external/get_groups_for_selector.php

@@ -0,0 +1,150 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\external;
+
+use context_course;
+use core_external\external_api;
+use core_external\external_description;
+use core_external\external_function_parameters;
+use core_external\external_multiple_structure;
+use core_external\external_single_structure;
+use core_external\external_value;
+use core_external\external_warnings;
+use core_grades\external\coding_exception;
+use core_grades\external\invalid_parameter_exception;
+use core_grades\external\moodle_exception;
+use core_grades\external\restricted_context_exception;
+use moodle_url;
+
+/**
+ * External group name and image API implementation
+ *
+ * @package    core_group
+ * @copyright  2022 Mathew May <mathew.solutions>
+ * @category   external
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class get_groups_for_selector extends external_api {
+
+    /**
+     * Returns description of method parameters.
+     *
+     * @return external_function_parameters
+     */
+    public static function execute_parameters(): external_function_parameters {
+        return new external_function_parameters (
+            [
+                'courseid' => new external_value(PARAM_INT, 'Course Id', VALUE_REQUIRED),
+            ]
+        );
+    }
+
+    /**
+     * Given a course ID find the existing user groups and map some fields to the returned array of group objects.
+     *
+     * @param int $courseid
+     * @return array Groups and warnings to pass back to the calling widget.
+     */
+    public static function execute(int $courseid): array {
+        global $DB, $USER, $OUTPUT;
+
+        $params = self::validate_parameters(
+            self::execute_parameters(),
+            [
+                'courseid' => $courseid,
+            ]
+        );
+
+        $warnings = [];
+        $context = context_course::instance($params['courseid']);
+        parent::validate_context($context);
+
+        $mappedgroups = [];
+        $course = $DB->get_record('course', ['id' => $params['courseid']]);
+        // Initialise the grade tracking object.
+        if ($groupmode = $course->groupmode) {
+            $aag = has_capability('moodle/site:accessallgroups', $context);
+
+            $usergroups = [];
+            $groupuserid = 0;
+            if ($groupmode == VISIBLEGROUPS || $aag) {
+                // Get user's own groups and put to the top.
+                $usergroups = groups_get_all_groups($course->id, $USER->id, $course->defaultgroupingid);
+            } else {
+                $groupuserid = $USER->id;
+            }
+            $allowedgroups = groups_get_all_groups($course->id, $groupuserid, $course->defaultgroupingid);
+
+            $allgroups = array_merge($allowedgroups, $usergroups);
+            // Filter out any duplicate groups.
+            $groupsmenu = array_intersect_key($allgroups, array_unique(array_column($allgroups, 'name')));
+
+            if (!$allowedgroups || $groupmode == VISIBLEGROUPS || $aag) {
+                array_unshift($groupsmenu, (object) [
+                    'id' => 0,
+                    'name' => get_string('allparticipants'),
+                ]);
+            }
+
+            $mappedgroups = array_map(function($group) use ($context, $OUTPUT) {
+                if ($group->id) { // Particular group. Get the group picture if it exists, otherwise return a generic image.
+                    $picture = get_group_picture_url($group, $group->courseid, true) ??
+                        moodle_url::make_pluginfile_url($context->id, 'group', 'generated', $group->id, '/', 'group.svg');
+                } else { // All participants.
+                    $picture = $OUTPUT->image_url('g/g1');
+                }
+
+                return (object) [
+                    'id' => $group->id,
+                    'name' => format_string($group->name, true, ['context' => $context]),
+                    'groupimageurl' => $picture->out(false),
+                ];
+            }, $groupsmenu);
+        }
+
+        return [
+            'groups' => $mappedgroups,
+            'warnings' => $warnings,
+        ];
+    }
+
+    /**
+     * Returns description of what the group search for the widget should return.
+     *
+     * @return external_single_structure
+     */
+    public static function execute_returns(): external_single_structure {
+        return new external_single_structure([
+            'groups' => new external_multiple_structure(self::group_description()),
+            'warnings' => new external_warnings(),
+        ]);
+    }
+
+    /**
+     * Create group return value description.
+     *
+     * @return external_description
+     */
+    public static function group_description(): external_description {
+        $groupfields = [
+            'id' => new external_value(PARAM_ALPHANUM, 'An ID for the group', VALUE_REQUIRED),
+            'name' => new external_value(PARAM_TEXT, 'The full name of the group', VALUE_REQUIRED),
+            'groupimageurl' => new external_value(PARAM_URL, 'Group image URL', VALUE_OPTIONAL),
+        ];
+        return new external_single_structure($groupfields);
+    }
+}

group/classes/hook/after_group_created.php

@@ -0,0 +1,41 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\hook;
+
+use stdClass;
+
+/**
+ * Hook after group creation.
+ *
+ * @package    core_group
+ * @copyright  2024 Safat Shahin <safat.shahin@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+#[\core\attribute\label('Allows plugins or features to perform actions after a group is created.')]
+#[\core\attribute\tags('group')]
+class after_group_created {
+    /**
+     * Constructor for the hook.
+     *
+     * @param stdClass $groupinstance The group instance.
+     */
+    public function __construct(
+        /** @var stdClass The group instance */
+        public readonly stdClass $groupinstance,
+    ) {
+    }
+}

group/classes/hook/after_group_deleted.php

@@ -0,0 +1,41 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\hook;
+
+use stdClass;
+
+/**
+ * Hook after group deletion.
+ *
+ * @package    core_group
+ * @copyright  2024 Safat Shahin <safat.shahin@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+#[\core\attribute\label('Allows plugins or features to perform actions after a group is deleted.')]
+#[\core\attribute\tags('group')]
+class after_group_deleted {
+    /**
+     * Constructor for the hook.
+     *
+     * @param stdClass $groupinstance The group instance.
+     */
+    public function __construct(
+        /** @var stdClass The group instance */
+        public readonly stdClass $groupinstance,
+    ) {
+    }
+}

group/classes/hook/after_group_membership_added.php

@@ -0,0 +1,44 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\hook;
+
+use stdClass;
+
+/**
+ * Hook after a member added to the group.
+ *
+ * @package    core_group
+ * @copyright  2023 Safat Shahin <safat.shahin@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+#[\core\attribute\label('Allows plugins or features to perform actions after members added to the group.')]
+#[\core\attribute\tags('group', 'user')]
+class after_group_membership_added {
+    /**
+     * Constructor for the hook.
+     *
+     * @param stdClass $groupinstance The group instance.
+     * @param array $userids The user ids.
+     */
+    public function __construct(
+        /** @var stdClass The group instance */
+        public readonly stdClass $groupinstance,
+        /** @var array The user ids */
+        public readonly array $userids,
+    ) {
+    }
+}

group/classes/hook/after_group_membership_removed.php

@@ -0,0 +1,44 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\hook;
+
+use stdClass;
+
+/**
+ * Hook after a member removed from the group.
+ *
+ * @package    core_group
+ * @copyright  2024 Safat Shahin <safat.shahin@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+#[\core\attribute\label('Allows plugins or features to perform actions after members removed from the group.')]
+#[\core\attribute\tags('group', 'user')]
+class after_group_membership_removed {
+    /**
+     * Constructor for the hook.
+     *
+     * @param stdClass $groupinstance The group instance.
+     * @param array $userids The user ids.
+     */
+    public function __construct(
+        /** @var stdClass The group instance */
+        public readonly stdClass $groupinstance,
+        /** @var array The user ids */
+        public readonly array $userids,
+    ) {
+    }
+}

group/classes/hook/after_group_updated.php

@@ -0,0 +1,41 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\hook;
+
+use stdClass;
+
+/**
+ * Hook after group updates.
+ *
+ * @package    core_group
+ * @copyright  2023 Safat Shahin <safat.shahin@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+#[\core\attribute\label('Allows plugins or features to perform actions after a group is updated.')]
+#[\core\attribute\tags('group')]
+class after_group_updated {
+    /**
+     * Constructor for the hook.
+     *
+     * @param stdClass $groupinstance The group instance.
+     */
+    public function __construct(
+        /** @var stdClass The group instance */
+        public readonly stdClass $groupinstance,
+    ) {
+    }
+}

group/classes/output/group_details.php

@@ -0,0 +1,93 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Group details page.
+ *
+ * @package    core_group
+ * @copyright  2017 Adrian Greeve <adrian@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core_group\output;
+defined('MOODLE_INTERNAL') || die();
+
+use renderable;
+use renderer_base;
+use stdClass;
+use templatable;
+use context_course;
+use moodle_url;
+
+/**
+ * Group details page class.
+ *
+ * @package    core_group
+ * @copyright  2017 Adrian Greeve <adrian@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class group_details implements renderable, templatable {
+
+    /** @var stdClass $group An object with the group information. */
+    protected $group;
+
+    /**
+     * group_details constructor.
+     *
+     * @param  int $groupid Group ID to show details of.
+     */
+    public function __construct($groupid) {
+        $this->group = groups_get_group($groupid, '*', MUST_EXIST);
+    }
+
+    /**
+     * Export the data.
+     *
+     * @param renderer_base $output
+     * @return stdClass
+     */
+    public function export_for_template(renderer_base $output) {
+
+        if (!empty($this->group->description) || (!empty($this->group->picture))) {
+            $context = context_course::instance($this->group->courseid);
+            $description = file_rewrite_pluginfile_urls($this->group->description,
+                                                        'pluginfile.php',
+                                                        $context->id,
+                                                        'group',
+                                                        'description',
+                                                        $this->group->id);
+
+            $descriptionformat = $this->group->descriptionformat ?? FORMAT_MOODLE;
+            $options = [
+                'overflowdiv' => true,
+                'context'     => $context
+            ];
+
+            $data = new stdClass();
+            $data->name = format_string($this->group->name, true, ['context' => $context]);
+            $data->pictureurl = get_group_picture_url($this->group, $this->group->courseid, true);
+            $data->description = format_text($description, $descriptionformat, $options);
+
+            if (has_capability('moodle/course:managegroups', $context)) {
+                $url = new moodle_url('/group/group.php', ['id' => $this->group->id, 'courseid' => $this->group->courseid]);
+                $data->editurl = $url->out(false);
+            }
+
+            return $data;
+        } else {
+            return;
+        }
+    }
+}

group/classes/output/index_page.php

@@ -0,0 +1,117 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Group index page.
+ *
+ * @package    core_group
+ * @copyright  2017 Jun Pataleta
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core_group\output;
+defined('MOODLE_INTERNAL') || die();
+
+use renderable;
+use renderer_base;
+use stdClass;
+use templatable;
+
+/**
+ * Group index page class.
+ *
+ * @package    core_group
+ * @copyright  2017 Jun Pataleta
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class index_page implements renderable, templatable {
+
+    /** @var int $courseid The course ID. */
+    public $courseid;
+
+    /** @var array The array of groups to be rendered. */
+    public $groups;
+
+    /** @var string The name of the currently selected group. */
+    public $selectedgroupname;
+
+    /** @var array The array of group members to be rendered, if a group is selected. */
+    public $selectedgroupmembers;
+
+    /** @var bool Whether to disable the add members/edit group buttons. */
+    public $disableaddedit;
+
+    /** @var bool Whether to disable the delete group button. */
+    public $disabledelete;
+
+    /** @var array Groups that can't be deleted by the user. */
+    public $undeletablegroups;
+
+    /** @var bool Whether to show/hide the messaging setting buttons. */
+    public $messagingsettingsvisible;
+
+    /**
+     * index_page constructor.
+     *
+     * @param int $courseid The course ID.
+     * @param array $groups The array of groups to be rendered.
+     * @param string $selectedgroupname The name of the currently selected group.
+     * @param array $selectedgroupmembers The array of group members to be rendered, if a group is selected.
+     * @param bool $disableaddedit Whether to disable the add members/edit group buttons.
+     * @param bool $disabledelete Whether to disable the delete group button.
+     * @param array $undeletablegroups Groups that can't be deleted by the user.
+     * @param bool $messagingsettingsvisible If the messaging settings buttons should be visible.
+     */
+    public function __construct($courseid, $groups, $selectedgroupname, $selectedgroupmembers, $disableaddedit, $disabledelete,
+                                $undeletablegroups, $messagingsettingsvisible) {
+        $this->courseid = $courseid;
+        $this->groups = $groups;
+        $this->selectedgroupname = $selectedgroupname;
+        $this->selectedgroupmembers = $selectedgroupmembers;
+        $this->disableaddedit = $disableaddedit;
+        $this->disabledelete = $disabledelete;
+        $this->undeletablegroups = $undeletablegroups;
+        $this->messagingsettingsvisible = $messagingsettingsvisible;
+    }
+
+    /**
+     * Export the data.
+     *
+     * @param renderer_base $output
+     * @return stdClass
+     */
+    public function export_for_template(renderer_base $output) {
+        global $CFG;
+
+        $data = new stdClass();
+
+        // Variables that will be passed to the JS helper.
+        $data->courseid = $this->courseid;
+        $data->wwwroot = $CFG->wwwroot;
+        // To be passed to the JS init script in the template. Encode as a JSON string.
+        $data->undeletablegroups = json_encode($this->undeletablegroups);
+
+        // Some buttons are enabled if single group selected.
+        $data->addmembersdisabled = $this->disableaddedit;
+        $data->editgroupsettingsdisabled = $this->disableaddedit;
+        $data->deletegroupdisabled = $this->disabledelete;
+        $data->groups = $this->groups;
+        $data->members = $this->selectedgroupmembers;
+        $data->selectedgroup = $this->selectedgroupname;
+        $data->messagingsettingsvisible = $this->messagingsettingsvisible;
+
+        return $data;
+    }
+}

group/classes/output/renderer.php

@@ -0,0 +1,61 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Renderers.
+ *
+ * @package    core_group
+ * @copyright  2017 Jun Pataleta
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core_group\output;
+
+defined('MOODLE_INTERNAL') || die();
+
+use plugin_renderer_base;
+
+/**
+ * Renderer class.
+ *
+ * @package    core_group
+ * @copyright  2017 Jun Pataleta
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class renderer extends plugin_renderer_base {
+
+    /**
+     * Defer to template.
+     *
+     * @param index_page $page
+     * @return string
+     */
+    public function render_index_page(index_page $page) {
+        $data = $page->export_for_template($this);
+        return parent::render_from_template('core_group/index', $data);
+    }
+
+    /**
+     * Defer to template.
+     *
+     * @param group_details $page Group details page object.
+     * @return string HTML to render the group details.
+     */
+    public function group_details(group_details $page) {
+        $data = $page->export_for_template($this);
+        return parent::render_from_template('core_group/group_details', $data);
+    }
+}

group/classes/output/user_groups_editable.php

@@ -0,0 +1,180 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Contains class core_group\output\user_groups_editable
+ *
+ * @package   core_group
+ * @copyright 2017 Damyon Wiese
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core_group\output;
+
+use context_course;
+use core_user;
+use core_external;
+use coding_exception;
+
+defined('MOODLE_INTERNAL') || die();
+
+require_once($CFG->dirroot . '/group/lib.php');
+
+/**
+ * Class to display list of user groups.
+ *
+ * @package   core_group
+ * @copyright 2017 Damyon Wiese
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class user_groups_editable extends \core\output\inplace_editable {
+
+    /** @var $coursegroups */
+    private $coursegroups = null;
+    /** @var $context */
+    private $context = null;
+
+    /**
+     * Constructor.
+     *
+     * @param \stdClass $course The current course
+     * @param \context $context The course context
+     * @param \stdClass $user The current user
+     * @param \stdClass[] $coursegroups The list of course groups from groups_get_all_groups with membership.
+     * @param array $value Array of groupids.
+     */
+    public function __construct($course, $context, $user, $coursegroups, $value) {
+        // Check capabilities to get editable value.
+        $editable = has_capability('moodle/course:managegroups', $context) && !empty($coursegroups);
+
+        // Invent an itemid.
+        $itemid = $course->id . ':' . $user->id;
+
+        $value = json_encode($value);
+
+        // Remember these for the display value.
+        $this->coursegroups = $coursegroups;
+        $this->context = $context;
+
+        parent::__construct('core_group', 'user_groups', $itemid, $editable, $value, $value);
+
+        // Assignable groups.
+        $options = [];
+
+        foreach ($coursegroups as $group) {
+            $options[$group->id] = format_string($group->name, true, ['context' => $this->context]);
+        }
+
+        $fullname = fullname($user, has_capability('moodle/site:viewfullnames', $this->context));
+        $fullname = htmlspecialchars($fullname, ENT_QUOTES, 'utf-8');
+        $this->edithint = get_string('editusersgroupsa', 'group', $fullname);
+        $this->editlabel = get_string('editusersgroupsa', 'group', $fullname);
+
+        $attributes = ['multiple' => true];
+        $this->set_type_autocomplete($options, $attributes);
+    }
+
+    /**
+     * Export this data so it can be used as the context for a mustache template.
+     *
+     * @param \renderer_base $output
+     * @return array
+     */
+    public function export_for_template(\renderer_base $output) {
+        $listofgroups = [];
+        $groupids = json_decode($this->value);
+        foreach ($groupids as $id) {
+            $listofgroups[] = format_string($this->coursegroups[$id]->name, true, ['context' => $this->context]);
+        }
+
+        if (!empty($listofgroups)) {
+            $this->displayvalue = implode(', ', $listofgroups);
+        } else {
+            $this->displayvalue = get_string('groupsnone');
+        }
+        return parent::export_for_template($output);
+    }
+
+    /**
+     * Updates the value in database and returns itself, called from inplace_editable callback
+     *
+     * @param int $itemid
+     * @param mixed $newvalue
+     * @return \self
+     */
+    public static function update($itemid, $newvalue) {
+        // Check caps.
+        // Do the thing.
+        // Return one of me.
+        // Validate the inputs.
+        list($courseid, $userid) = explode(':', $itemid, 2);
+
+        $courseid = clean_param($courseid, PARAM_INT);
+        $userid = clean_param($userid, PARAM_INT);
+        $groupids = json_decode($newvalue);
+        foreach ($groupids as $index => $groupid) {
+            $groupids[$index] = clean_param($groupid, PARAM_INT);
+        }
+
+        // Check user is enrolled in the course.
+        $context = context_course::instance($courseid);
+        core_external::validate_context($context);
+
+        if (!is_enrolled($context, $userid)) {
+            throw new coding_exception('User does not belong to the course');
+        }
+
+        // Check that all the groups belong to the course.
+        $coursegroups = groups_get_all_groups($courseid, 0, 0, 'g.*', true);
+
+        $byid = [];
+        foreach ($groupids as $groupid) {
+            if (!isset($coursegroups[$groupid])) {
+                throw new coding_exception('Group does not belong to the course');
+            }
+            $byid[$groupid] = $groupid;
+        }
+        $groupids = $byid;
+        // Check permissions.
+        require_capability('moodle/course:managegroups', $context);
+
+        // Process adds.
+        foreach ($groupids as $groupid) {
+            if (!isset($coursegroups[$groupid]->members[$userid])) {
+                // Add them.
+                groups_add_member($groupid, $userid);
+                // Keep this variable in sync.
+                $coursegroups[$groupid]->members[$userid] = $userid;
+            }
+        }
+
+        // Process removals.
+        foreach ($coursegroups as $groupid => $group) {
+            if (isset($group->members[$userid]) && !isset($groupids[$groupid])) {
+                if (groups_remove_member_allowed($groupid, $userid)) {
+                    groups_remove_member($groupid, $userid);
+                    unset($coursegroups[$groupid]->members[$userid]);
+                } else {
+                    $groupids[$groupid] = $groupid;
+                }
+            }
+        }
+
+        $course = get_course($courseid);
+        $user = core_user::get_user($userid);
+        return new self($course, $context, $user, $coursegroups, array_values($groupids));
+    }
+}

group/classes/privacy/provider.php

@@ -0,0 +1,400 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Privacy Subsystem implementation for core_group.
+ *
+ * @package    core_group
+ * @category   privacy
+ * @copyright  2018 Shamim Rezaie <shamim@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core_group\privacy;
+
+defined('MOODLE_INTERNAL') || die();
+
+use core_privacy\local\metadata\collection;
+use core_privacy\local\request\approved_contextlist;
+use core_privacy\local\request\approved_userlist;
+use core_privacy\local\request\contextlist;
+use core_privacy\local\request\transform;
+use core_privacy\local\request\userlist;
+
+/**
+ * Privacy Subsystem implementation for core_group.
+ *
+ * @copyright  2018 Shamim Rezaie <shamim@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class provider implements
+        // Groups store user data.
+        \core_privacy\local\metadata\provider,
+
+        // The group subsystem contains user's group memberships.
+        \core_privacy\local\request\subsystem\provider,
+
+        // The group subsystem can provide information to other plugins.
+        \core_privacy\local\request\subsystem\plugin_provider,
+
+        // This plugin is capable of determining which users have data within it.
+        \core_privacy\local\request\core_userlist_provider,
+        \core_privacy\local\request\shared_userlist_provider
+    {
+
+    /**
+     * Returns meta data about this system.
+     *
+     * @param   collection $collection The initialised collection to add items to.
+     * @return  collection A listing of user data stored through this system.
+     */
+    public static function get_metadata(collection $collection): collection {
+        $collection->add_database_table('groups_members', [
+            'groupid' => 'privacy:metadata:groups:groupid',
+            'userid' => 'privacy:metadata:groups:userid',
+            'timeadded' => 'privacy:metadata:groups:timeadded',
+        ], 'privacy:metadata:groups');
+
+        $collection->link_subsystem('core_message', 'privacy:metadata:core_message');
+
+        return $collection;
+    }
+
+    /**
+     * Writes user data to the writer for the user to download.
+     *
+     * @param \context  $context    The context to export data for.
+     * @param string    $component  The component that is calling this function. Empty string means no component.
+     * @param array     $subcontext The sub-context in which to export this data.
+     * @param int       $itemid     Optional itemid associated with component.
+     */
+    public static function export_groups(\context $context, string $component, array $subcontext = [], int $itemid = 0) {
+        global $DB, $USER;
+
+        if (!$context instanceof \context_course) {
+            return;
+        }
+
+        $subcontext[] = get_string('groups', 'core_group');
+
+        $sql = "SELECT gm.id, gm.timeadded, gm.userid, g.name, gm.groupid
+                  FROM {groups_members} gm
+                  JOIN {groups} g ON gm.groupid = g.id
+                 WHERE g.courseid = :courseid
+                       AND gm.component = :component
+                       AND gm.userid = :userid";
+        $params = [
+            'courseid'  => $context->instanceid,
+            'component' => $component,
+            'userid'    => $USER->id
+        ];
+
+        if ($itemid) {
+            $sql .= ' AND gm.itemid = :itemid';
+            $params['itemid'] = $itemid;
+        }
+
+        $groups = $DB->get_records_sql($sql, $params);
+
+        $groupstoexport = array_map(function($group) {
+            return (object) [
+                'name' => format_string($group->name),
+                'timeadded' => transform::datetime($group->timeadded),
+            ];
+        }, $groups);
+
+        if (!empty($groups)) {
+            \core_privacy\local\request\writer::with_context($context)
+                    ->export_data($subcontext, (object) [
+                        'groups' => $groupstoexport,
+                    ]);
+
+            foreach ($groups as $group) {
+                // Export associated conversations to this group.
+                \core_message\privacy\provider::export_conversations($USER->id, 'core_group', 'groups',
+                    $context, [], $group->groupid);
+            }
+        }
+    }
+
+    /**
+     * Deletes all group memberships for a specified context and component.
+     *
+     * @param \context  $context    Details about which context to delete group memberships for.
+     * @param string    $component  Component to delete. Empty string means no component (manual group memberships).
+     * @param int       $itemid     Optional itemid associated with component.
+     */
+    public static function delete_groups_for_all_users(\context $context, string $component, int $itemid = 0) {
+        global $DB;
+
+        if (!$context instanceof \context_course) {
+            return;
+        }
+
+        if (!$DB->record_exists('groups', ['courseid' => $context->instanceid])) {
+            return;
+        }
+
+        $select = "component = :component AND groupid IN (SELECT g.id FROM {groups} g WHERE courseid = :courseid)";
+        $params = ['component' => $component, 'courseid' => $context->instanceid];
+
+        if ($itemid) {
+            $select .= ' AND itemid = :itemid';
+            $params['itemid'] = $itemid;
+        }
+
+        // Delete the group conversations.
+        $groups = $DB->get_records_select('groups_members', $select, $params);
+        foreach ($groups as $group) {
+            \core_message\privacy\provider::delete_conversations_for_all_users($context, 'core_group', 'groups', $group->groupid);
+        }
+
+        // Remove members from the group.
+        $DB->delete_records_select('groups_members', $select, $params);
+
+        // Purge the group and grouping cache for users.
+        \cache_helper::purge_by_definition('core', 'user_group_groupings');
+    }
+
+    /**
+     * Deletes all records for a user from a list of approved contexts.
+     *
+     * @param approved_contextlist  $contextlist    Contains the user ID and a list of contexts to be deleted from.
+     * @param string                $component      Component to delete from. Empty string means no component (manual memberships).
+     * @param int                   $itemid         Optional itemid associated with component.
+     */
+    public static function delete_groups_for_user(approved_contextlist $contextlist, string $component, int $itemid = 0) {
+        global $DB;
+
+        $userid = $contextlist->get_user()->id;
+
+        $contextids = $contextlist->get_contextids();
+
+        if (!$contextids) {
+            return;
+        }
+
+        list($contextsql, $contextparams) = $DB->get_in_or_equal($contextids, SQL_PARAMS_NAMED);
+        $contextparams += ['contextcourse' => CONTEXT_COURSE];
+        $groupselect = "SELECT g.id
+                          FROM {groups} g
+                          JOIN {context} ctx ON g.courseid = ctx.instanceid AND ctx.contextlevel = :contextcourse
+                         WHERE ctx.id $contextsql";
+
+        if (!$DB->record_exists_sql($groupselect, $contextparams)) {
+            return;
+        }
+
+        $select = "userid = :userid AND component = :component AND groupid IN ({$groupselect})";
+        $params = ['userid' => $userid, 'component' => $component] + $contextparams;
+
+        if ($itemid) {
+            $select .= ' AND itemid = :itemid';
+            $params['itemid'] = $itemid;
+        }
+
+        // Delete the group conversations.
+        $groups = $DB->get_records_select('groups_members', $select, $params);
+        foreach ($groups as $group) {
+            \core_message\privacy\provider::delete_conversations_for_user($contextlist, 'core_group', 'groups', $group->groupid);
+        }
+
+        // Remove members from the group.
+        $DB->delete_records_select('groups_members', $select, $params);
+
+        // Invalidate the group and grouping cache for the user.
+        \cache_helper::invalidate_by_definition('core', 'user_group_groupings', array(), array($userid));
+    }
+
+    /**
+     * Add the list of users who are members of some groups in the specified constraints.
+     *
+     * @param   userlist    $userlist   The userlist to add the users to.
+     * @param   string      $component  The component to check.
+     * @param   int         $itemid     Optional itemid associated with component.
+     */
+    public static function get_group_members_in_context(userlist $userlist, string $component, int $itemid = 0) {
+        $context = $userlist->get_context();
+
+        if (!$context instanceof \context_course) {
+            return;
+        }
+
+        // Group members in the given context.
+        $sql = "SELECT gm.userid
+                  FROM {groups_members} gm
+                  JOIN {groups} g ON gm.groupid = g.id
+                 WHERE g.courseid = :courseid AND gm.component = :component";
+        $params = [
+            'courseid'      => $context->instanceid,
+            'component'     => $component
+        ];
+
+        if ($itemid) {
+            $sql .= ' AND gm.itemid = :itemid';
+            $params['itemid'] = $itemid;
+        }
+
+        $userlist->add_from_sql('userid', $sql, $params);
+
+        // Get the users with some group conversation in this context.
+        \core_message\privacy\provider::add_conversations_in_context($userlist, 'core_group', 'groups', $itemid);
+    }
+
+    /**
+     * Deletes all records for multiple users within a single context.
+     *
+     * @param approved_userlist $userlist   The approved context and user information to delete information for.
+     * @param string            $component  Component to delete from. Empty string means no component (manual memberships).
+     * @param int               $itemid     Optional itemid associated with component.
+     */
+    public static function delete_groups_for_users(approved_userlist $userlist, string $component, int $itemid = 0) {
+        global $DB;
+
+        $context = $userlist->get_context();
+        $userids = $userlist->get_userids();
+
+        if (!$context instanceof \context_course) {
+            return;
+        }
+
+        list($usersql, $userparams) = $DB->get_in_or_equal($userids, SQL_PARAMS_NAMED);
+
+        $groupselect = "SELECT id FROM {groups} WHERE courseid = :courseid";
+        $groupparams = ['courseid' => $context->instanceid];
+
+        $select = "component = :component AND userid {$usersql} AND groupid IN ({$groupselect})";
+        $params = ['component' => $component] + $groupparams + $userparams;
+
+        if ($itemid) {
+            $select .= ' AND itemid = :itemid';
+            $params['itemid'] = $itemid;
+        }
+
+        // Delete the group conversations for these users.
+        $groups = $DB->get_records_select('groups_members', $select, $params);
+        foreach ($groups as $group) {
+            \core_message\privacy\provider::delete_conversations_for_users($userlist, 'core_group', 'groups', $group->groupid);
+        }
+
+        $DB->delete_records_select('groups_members', $select, $params);
+
+        // Invalidate the group and grouping cache for the user.
+        \cache_helper::invalidate_by_definition('core', 'user_group_groupings', array(), $userids);
+    }
+
+    /**
+     * Get the list of contexts that contain group membership for the specified user.
+     *
+     * @param   int     $userid     The user to search.
+     * @param   string  $component  The component to check.
+     * @param   int     $itemid     Optional itemid associated with component.
+     * @return  contextlist         The contextlist containing the list of contexts.
+     */
+    public static function get_contexts_for_group_member(int $userid, string $component, int $itemid = 0) {
+        $contextlist = new contextlist();
+
+        $sql = "SELECT ctx.id
+                  FROM {groups_members} gm
+                  JOIN {groups} g ON gm.groupid = g.id
+                  JOIN {context} ctx ON g.courseid = ctx.instanceid AND ctx.contextlevel = :contextcourse
+                 WHERE gm.userid = :userid AND gm.component = :component";
+
+        $params = [
+            'contextcourse' => CONTEXT_COURSE,
+            'userid'        => $userid,
+            'component'     => $component
+        ];
+
+        if ($itemid) {
+            $sql .= ' AND gm.itemid = :itemid';
+            $params['itemid'] = $itemid;
+        }
+
+        $contextlist->add_from_sql($sql, $params);
+
+        // Get the contexts where the userid has group conversations.
+        \core_message\privacy\provider::add_contexts_for_conversations($contextlist, $userid, 'core_group', 'groups', $itemid);
+
+        return $contextlist;
+    }
+
+    /**
+     * Get the list of users who have data within a context.
+     *
+     * @param   int $userid The user to search.
+     * @return  contextlist The contextlist containing the list of contexts used in this plugin.
+     */
+    public static function get_contexts_for_userid(int $userid): contextlist {
+        return static::get_contexts_for_group_member($userid, '');
+    }
+
+    /**
+     * Get the list of users who have data within a context.
+     *
+     * @param   userlist    $userlist   The userlist containing the list of users who have data in this context/plugin combination.
+     */
+    public static function get_users_in_context(userlist $userlist) {
+        $context = $userlist->get_context();
+
+        if (!$context instanceof \context_course) {
+            return;
+        }
+
+        static::get_group_members_in_context($userlist, '');
+    }
+
+    /**
+     * Export all user data for the specified user, in the specified contexts.
+     *
+     * @param approved_contextlist $contextlist The approved contexts to export information for.
+     */
+    public static function export_user_data(approved_contextlist $contextlist) {
+        $contexts = $contextlist->get_contexts();
+
+        foreach ($contexts as $context) {
+            static::export_groups($context, '');
+        }
+    }
+
+    /**
+     * Delete all data for all users in the specified context.
+     *
+     * @param context $context The specific context to delete data for.
+     */
+    public static function delete_data_for_all_users_in_context(\context $context) {
+        static::delete_groups_for_all_users($context, '');
+    }
+
+    /**
+     * Delete all user data for the specified user, in the specified contexts.
+     *
+     * @param approved_contextlist $contextlist The approved contexts and user information to delete information for.
+     */
+    public static function delete_data_for_user(approved_contextlist $contextlist) {
+        static::delete_groups_for_user($contextlist, '');
+    }
+
+    /**
+     * Delete multiple users within a single context.
+     *
+     * @param   approved_userlist   $userlist   The approved context and user information to delete information for.
+     */
+    public static function delete_data_for_users(approved_userlist $userlist) {
+        static::delete_groups_for_users($userlist, '');
+    }
+
+}

group/classes/reportbuilder/datasource/groups.php

@@ -0,0 +1,151 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+declare(strict_types=1);
+
+namespace core_group\reportbuilder\datasource;
+
+use core_group\reportbuilder\local\entities\{grouping, group, group_member};
+use core_reportbuilder\datasource;
+use core_reportbuilder\local\entities\{course, user};
+use core_reportbuilder\local\helpers\database;
+
+/**
+ * Groups datasource
+ *
+ * @package     core_group
+ * @copyright   2022 Paul Holden <paulh@moodle.com>
+ * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class groups extends datasource {
+
+    /**
+     * Return user friendly name of the datasource
+     *
+     * @return string
+     */
+    public static function get_name(): string {
+        return get_string('groups', 'core_group');
+    }
+
+    /**
+     * Initialise report
+     */
+    protected function initialise(): void {
+        $courseentity = new course();
+        $coursealias = $courseentity->get_table_alias('course');
+
+        $this->set_main_table('course', $coursealias);
+        $this->add_entity($courseentity);
+
+        $paramsiteid = database::generate_param_name();
+        $this->add_base_condition_sql("{$coursealias}.id != :{$paramsiteid}", [$paramsiteid => SITEID]);
+
+        // Re-use the context table alias/join from the course entity in subsequent entities.
+        $contextalias = $courseentity->get_table_alias('context');
+        $this->add_join($courseentity->get_context_join());
+
+        // Group entity.
+        $groupentity = (new group())
+            ->set_table_alias('context', $contextalias);
+        $groupsalias = $groupentity->get_table_alias('groups');
+        $this->add_entity($groupentity
+            ->add_join("LEFT JOIN {groups} {$groupsalias} ON {$groupsalias}.courseid = {$coursealias}.id"));
+
+        // Grouping entity.
+        $groupingentity = (new grouping())
+            ->set_table_alias('context', $contextalias);
+        $groupingsalias = $groupingentity->get_table_alias('groupings');
+
+        // Sub-select for all groupings groups.
+        $groupinginnerselect = "
+            SELECT gr.*, grg.groupid
+              FROM {groupings} gr
+              JOIN {groupings_groups} grg ON grg.groupingid = gr.id";
+
+        $this->add_entity($groupingentity
+            ->add_joins($groupentity->get_joins())
+            ->add_join("LEFT JOIN ({$groupinginnerselect}) {$groupingsalias}
+                ON {$groupingsalias}.courseid = {$coursealias}.id AND {$groupingsalias}.groupid = {$groupsalias}.id"));
+
+        // Group member entity.
+        $groupmemberentity = new group_member();
+        $groupsmembersalias = $groupmemberentity->get_table_alias('groups_members');
+        $this->add_entity($groupmemberentity
+            ->add_joins($groupentity->get_joins())
+            ->add_join("LEFT JOIN {groups_members} {$groupsmembersalias} ON {$groupsmembersalias}.groupid = {$groupsalias}.id"));
+
+        // User entity.
+        $userentity = new user();
+        $useralias = $userentity->get_table_alias('user');
+        $this->add_entity($userentity
+            ->add_joins($groupmemberentity->get_joins())
+            ->add_join("LEFT JOIN {user} {$useralias} ON {$useralias}.id = {$groupsmembersalias}.userid"));
+
+        // Add all elements from entities to be available in custom reports.
+        $this->add_all_from_entities();
+    }
+
+    /**
+     * Return the columns that will be added to the report as part of default setup
+     *
+     * @return string[]
+     */
+    public function get_default_columns(): array {
+        return [
+            'course:coursefullnamewithlink',
+            'group:name',
+            'user:fullname',
+        ];
+    }
+
+    /**
+     * Return the column sorting that will be added to the report upon creation
+     *
+     * @return int[]
+     */
+    public function get_default_column_sorting(): array {
+        return [
+            'course:coursefullnamewithlink' => SORT_ASC,
+            'group:name' => SORT_ASC,
+            'user:fullname' => SORT_ASC,
+        ];
+    }
+
+    /**
+     * Return the filters that will be added to the report as part of default setup
+     *
+     * @return string[]
+     */
+    public function get_default_filters(): array {
+        return [
+            'course:fullname',
+            'group:name',
+        ];
+    }
+
+    /**
+     * Return the conditions that will be added to the report as part of default setup
+     *
+     * @return string[]
+     */
+    public function get_default_conditions(): array {
+        return [
+            'course:fullname',
+            'group:name',
+        ];
+    }
+}

group/classes/reportbuilder/local/entities/group.php

@@ -0,0 +1,343 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+declare(strict_types=1);
+
+namespace core_group\reportbuilder\local\entities;
+
+use context_course;
+use context_helper;
+use html_writer;
+use lang_string;
+use moodle_url;
+use stdClass;
+use core_reportbuilder\local\entities\base;
+use core_reportbuilder\local\filters\{boolean_select, date, select, text};
+use core_reportbuilder\local\helpers\{custom_fields, format};
+use core_reportbuilder\local\report\{column, filter};
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once("{$CFG->libdir}/grouplib.php");
+
+/**
+ * Group entity
+ *
+ * @package     core_group
+ * @copyright   2022 Paul Holden <paulh@moodle.com>
+ * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class group extends base {
+
+    /**
+     * Database tables that this entity uses
+     *
+     * @return string[]
+     */
+    protected function get_default_tables(): array {
+        return [
+            'context',
+            'groups',
+        ];
+    }
+
+    /**
+     * The default title for this entity
+     *
+     * @return lang_string
+     */
+    protected function get_default_entity_title(): lang_string {
+        return new lang_string('group', 'core_group');
+    }
+
+    /**
+     * Initialise the entity
+     *
+     * @return base
+     */
+    public function initialise(): base {
+        $groupsalias = $this->get_table_alias('groups');
+
+        $customfields = (new custom_fields(
+            "{$groupsalias}.id",
+            $this->get_entity_name(),
+            'core_group',
+            'group',
+        ))
+            ->add_joins($this->get_joins());
+
+        $columns = array_merge($this->get_all_columns(), $customfields->get_columns());
+        foreach ($columns as $column) {
+            $this->add_column($column);
+        }
+
+        // All the filters defined by the entity can also be used as conditions.
+        $filters = array_merge($this->get_all_filters(), $customfields->get_filters());
+        foreach ($filters as $filter) {
+            $this
+                ->add_filter($filter)
+                ->add_condition($filter);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Returns list of all available columns
+     *
+     * @return column[]
+     */
+    protected function get_all_columns(): array {
+        global $DB;
+
+        $contextalias = $this->get_table_alias('context');
+        $groupsalias = $this->get_table_alias('groups');
+
+        // Name column.
+        $columns[] = (new column(
+            'name',
+            new lang_string('name'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TEXT)
+            ->add_fields("{$groupsalias}.name, {$groupsalias}.courseid")
+            ->add_fields(context_helper::get_preload_record_columns_sql($contextalias))
+            ->set_is_sortable(true)
+            ->set_callback(static function($name, stdClass $group): string {
+                if ($name === null) {
+                    return '';
+                }
+
+                context_helper::preload_from_record($group);
+                $context = context_course::instance($group->courseid);
+
+                return format_string($group->name, true, ['context' => $context]);
+            });
+
+        // ID number column.
+        $columns[] = (new column(
+            'idnumber',
+            new lang_string('idnumber'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TEXT)
+            ->add_fields("{$groupsalias}.idnumber")
+            ->set_is_sortable(true);
+
+        // Description column.
+        $descriptionfieldsql = "{$groupsalias}.description";
+        if ($DB->get_dbfamily() === 'oracle') {
+            $descriptionfieldsql = $DB->sql_order_by_text($descriptionfieldsql, 1024);
+        }
+        $columns[] = (new column(
+            'description',
+            new lang_string('description'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_LONGTEXT)
+            ->add_field($descriptionfieldsql, 'description')
+            ->add_fields("{$groupsalias}.descriptionformat, {$groupsalias}.id, {$groupsalias}.courseid")
+            ->add_fields(context_helper::get_preload_record_columns_sql($contextalias))
+            ->set_is_sortable(false)
+            ->set_callback(static function(?string $description, stdClass $group): string {
+                global $CFG;
+
+                if ($description === null) {
+                    return '';
+                }
+
+                require_once("{$CFG->libdir}/filelib.php");
+
+                context_helper::preload_from_record($group);
+                $context = context_course::instance($group->courseid);
+
+                $description = file_rewrite_pluginfile_urls($description, 'pluginfile.php', $context->id, 'group',
+                    'description', $group->id);
+
+                return format_text($description, $group->descriptionformat, ['context' => $context]);
+            });
+
+        // Enrolment key column.
+        $columns[] = (new column(
+            'enrolmentkey',
+            new lang_string('enrolmentkey', 'core_group'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TEXT)
+            ->add_fields("{$groupsalias}.enrolmentkey")
+            ->set_is_sortable(true);
+
+        // Visibility column.
+        $columns[] = (new column(
+            'visibility',
+            new lang_string('visibilityshort', 'core_group'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_INTEGER)
+            ->add_fields("{$groupsalias}.visibility")
+            ->set_is_sortable(true)
+            // It doesn't make sense to offer integer aggregation methods for this column.
+            ->set_disabled_aggregation(['avg', 'max', 'min', 'sum'])
+            ->set_callback(static function(?int $visibility): string {
+                if ($visibility === null) {
+                    return '';
+                }
+
+                $options = [
+                    GROUPS_VISIBILITY_ALL => new lang_string('visibilityall', 'core_group'),
+                    GROUPS_VISIBILITY_MEMBERS => new lang_string('visibilitymembers', 'core_group'),
+                    GROUPS_VISIBILITY_OWN => new lang_string('visibilityown', 'core_group'),
+                    GROUPS_VISIBILITY_NONE => new lang_string('visibilitynone', 'core_group'),
+                ];
+
+                return (string) ($options[$visibility] ?? $visibility);
+            });
+
+        // Participation column.
+        $columns[] = (new column(
+            'participation',
+            new lang_string('participationshort', 'core_group'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_BOOLEAN)
+            ->add_fields("{$groupsalias}.participation")
+            ->set_is_sortable(true)
+            ->set_callback([format::class, 'boolean_as_text']);
+
+        // Picture column.
+        $columns[] = (new column(
+            'picture',
+            new lang_string('picture'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_INTEGER)
+            ->add_fields("{$groupsalias}.picture, {$groupsalias}.id, {$contextalias}.id AS contextid")
+            ->set_is_sortable(false)
+            // It doesn't make sense to offer integer aggregation methods for this column.
+            ->set_disabled_aggregation(['avg', 'max', 'min', 'sum'])
+            ->set_callback(static function ($picture, stdClass $group): string {
+                if (empty($group->picture)) {
+                    return '';
+                }
+
+                $pictureurl = moodle_url::make_pluginfile_url($group->contextid, 'group', 'icon', $group->id, '/', 'f2');
+                $pictureurl->param('rev', $group->picture);
+
+                return html_writer::img($pictureurl, '');
+            });
+
+        // Time created column.
+        $columns[] = (new column(
+            'timecreated',
+            new lang_string('timecreated', 'core_reportbuilder'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TIMESTAMP)
+            ->add_fields("{$groupsalias}.timecreated")
+            ->set_is_sortable(true)
+            ->set_callback([format::class, 'userdate']);
+
+        // Time modified column.
+        $columns[] = (new column(
+            'timemodified',
+            new lang_string('timemodified', 'core_reportbuilder'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TIMESTAMP)
+            ->add_fields("{$groupsalias}.timemodified")
+            ->set_is_sortable(true)
+            ->set_callback([format::class, 'userdate']);
+
+        return $columns;
+    }
+
+    /**
+     * Return list of all available filters
+     *
+     * @return filter[]
+     */
+    protected function get_all_filters(): array {
+        $groupsalias = $this->get_table_alias('groups');
+
+        // Name filter.
+        $filters[] = (new filter(
+            text::class,
+            'name',
+            new lang_string('name'),
+            $this->get_entity_name(),
+            "{$groupsalias}.name"
+        ))
+            ->add_joins($this->get_joins());
+
+        // ID number filter.
+        $filters[] = (new filter(
+            text::class,
+            'idnumber',
+            new lang_string('idnumber'),
+            $this->get_entity_name(),
+            "{$groupsalias}.idnumber"
+        ))
+            ->add_joins($this->get_joins());
+
+        // Visibility filter.
+        $filters[] = (new filter(
+            select::class,
+            'visibility',
+            new lang_string('visibilityshort', 'core_group'),
+            $this->get_entity_name(),
+            "{$groupsalias}.visibility"
+        ))
+            ->add_joins($this->get_joins())
+            ->set_options([
+                GROUPS_VISIBILITY_ALL => new lang_string('visibilityall', 'core_group'),
+                GROUPS_VISIBILITY_MEMBERS => new lang_string('visibilitymembers', 'core_group'),
+                GROUPS_VISIBILITY_OWN => new lang_string('visibilityown', 'core_group'),
+                GROUPS_VISIBILITY_NONE => new lang_string('visibilitynone', 'core_group'),
+            ]);
+
+        // Participation filter.
+        $filters[] = (new filter(
+            boolean_select::class,
+            'participation',
+            new lang_string('participationshort', 'core_group'),
+            $this->get_entity_name(),
+            "{$groupsalias}.participation"
+        ))
+            ->add_joins($this->get_joins());
+
+        // Time created filter.
+        $filters[] = (new filter(
+            date::class,
+            'timecreated',
+            new lang_string('timecreated', 'core_reportbuilder'),
+            $this->get_entity_name(),
+            "{$groupsalias}.timecreated"
+        ))
+            ->add_joins($this->get_joins());
+
+        return $filters;
+    }
+}

group/classes/reportbuilder/local/entities/group_member.php

@@ -0,0 +1,132 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+declare(strict_types=1);
+
+namespace core_group\reportbuilder\local\entities;
+
+use core_reportbuilder\local\filters\date;
+use lang_string;
+use core_reportbuilder\local\entities\base;
+use core_reportbuilder\local\helpers\format;
+use core_reportbuilder\local\report\{column, filter};
+
+/**
+ * Group member entity
+ *
+ * @package     core_group
+ * @copyright   2022 Paul Holden <paulh@moodle.com>
+ * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class group_member extends base {
+
+    /**
+     * Database tables that this entity uses
+     *
+     * @return string[]
+     */
+    protected function get_default_tables(): array {
+        return [
+            'groups_members',
+        ];
+    }
+
+    /**
+     * The default title for this entity
+     *
+     * @return lang_string
+     */
+    protected function get_default_entity_title(): lang_string {
+        return new lang_string('groupmember', 'core_group');
+    }
+
+    /**
+     * Initialise the entity
+     *
+     * @return base
+     */
+    public function initialise(): base {
+        $columns = $this->get_all_columns();
+        foreach ($columns as $column) {
+            $this->add_column($column);
+        }
+
+        // All the filters defined by the entity can also be used as conditions.
+        $filters = $this->get_all_filters();
+        foreach ($filters as $filter) {
+            $this
+                ->add_filter($filter)
+                ->add_condition($filter);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Returns list of all available columns
+     *
+     * @return column[]
+     */
+    protected function get_all_columns(): array {
+        $groupsmembersalias = $this->get_table_alias('groups_members');
+
+        // Time added column.
+        $columns[] = (new column(
+            'timeadded',
+            new lang_string('timeadded', 'core_reportbuilder'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TIMESTAMP)
+            ->add_fields("{$groupsmembersalias}.timeadded")
+            ->set_is_sortable(true)
+            ->set_callback([format::class, 'userdate']);
+
+        // Component column.
+        $columns[] = (new column(
+            'component',
+            new lang_string('plugin', 'core'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TEXT)
+            ->add_fields("{$groupsmembersalias}.component")
+            ->set_is_sortable(true);
+
+        return $columns;
+    }
+
+    /**
+     * Return list of all available filters
+     *
+     * @return filter[]
+     */
+    protected function get_all_filters(): array {
+        $groupsmembersalias = $this->get_table_alias('groups_members');
+
+        // Time added filter.
+        $filters[] = (new filter(
+            date::class,
+            'timeadded',
+            new lang_string('timeadded', 'core_reportbuilder'),
+            $this->get_entity_name(),
+            "{$groupsmembersalias}.timeadded"
+        ))
+            ->add_joins($this->get_joins());
+
+        return $filters;
+    }
+}

group/classes/reportbuilder/local/entities/grouping.php

@@ -0,0 +1,237 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+declare(strict_types=1);
+
+namespace core_group\reportbuilder\local\entities;
+
+use context_course;
+use context_helper;
+use lang_string;
+use stdClass;
+use core_reportbuilder\local\entities\base;
+use core_reportbuilder\local\filters\{date, text};
+use core_reportbuilder\local\helpers\{custom_fields, format};
+use core_reportbuilder\local\report\{column, filter};
+
+/**
+ * Grouping entity
+ *
+ * @package     core_group
+ * @copyright   2022 Paul Holden <paulh@moodle.com>
+ * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class grouping extends base {
+
+    /**
+     * Database tables that this entity uses
+     *
+     * @return string[]
+     */
+    protected function get_default_tables(): array {
+        return [
+            'context',
+            'groupings',
+        ];
+    }
+
+    /**
+     * The default title for this entity
+     *
+     * @return lang_string
+     */
+    protected function get_default_entity_title(): lang_string {
+        return new lang_string('grouping', 'core_group');
+    }
+
+    /**
+     * Initialise the entity
+     *
+     * @return base
+     */
+    public function initialise(): base {
+        $groupingsalias = $this->get_table_alias('groupings');
+
+        $customfields = (new custom_fields(
+            "{$groupingsalias}.id",
+            $this->get_entity_name(),
+            'core_group',
+            'grouping',
+        ))
+            ->add_joins($this->get_joins());
+
+        $columns = array_merge($this->get_all_columns(), $customfields->get_columns());
+        foreach ($columns as $column) {
+            $this->add_column($column);
+        }
+
+        // All the filters defined by the entity can also be used as conditions.
+        $filters = array_merge($this->get_all_filters(), $customfields->get_filters());
+        foreach ($filters as $filter) {
+            $this
+                ->add_filter($filter)
+                ->add_condition($filter);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Returns list of all available columns
+     *
+     * @return column[]
+     */
+    protected function get_all_columns(): array {
+        global $DB;
+
+        $contextalias = $this->get_table_alias('context');
+        $groupingsalias = $this->get_table_alias('groupings');
+
+        // Name column.
+        $columns[] = (new column(
+            'name',
+            new lang_string('name'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TEXT)
+            ->add_fields("{$groupingsalias}.name, {$groupingsalias}.courseid")
+            ->add_fields(context_helper::get_preload_record_columns_sql($contextalias))
+            ->set_is_sortable(true)
+            ->set_callback(static function($name, stdClass $grouping): string {
+                if ($name === null) {
+                    return '';
+                }
+
+                context_helper::preload_from_record($grouping);
+                $context = context_course::instance($grouping->courseid);
+
+                return format_string($grouping->name, true, ['context' => $context]);
+            });
+
+        // ID number column.
+        $columns[] = (new column(
+            'idnumber',
+            new lang_string('idnumber'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TEXT)
+            ->add_fields("{$groupingsalias}.idnumber")
+            ->set_is_sortable(true);
+
+        // Description column.
+        $descriptionfieldsql = "{$groupingsalias}.description";
+        if ($DB->get_dbfamily() === 'oracle') {
+            $descriptionfieldsql = $DB->sql_order_by_text($descriptionfieldsql, 1024);
+        }
+        $columns[] = (new column(
+            'description',
+            new lang_string('description'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_LONGTEXT)
+            ->add_field($descriptionfieldsql, 'description')
+            ->add_fields("{$groupingsalias}.descriptionformat, {$groupingsalias}.id, {$groupingsalias}.courseid")
+            ->add_fields(context_helper::get_preload_record_columns_sql($contextalias))
+            ->set_is_sortable(false)
+            ->set_callback(static function(?string $description, stdClass $grouping): string {
+                global $CFG;
+
+                if ($description === null) {
+                    return '';
+                }
+
+                require_once("{$CFG->libdir}/filelib.php");
+
+                context_helper::preload_from_record($grouping);
+                $context = context_course::instance($grouping->courseid);
+
+                $description = file_rewrite_pluginfile_urls($description, 'pluginfile.php', $context->id, 'grouping',
+                    'description', $grouping->id);
+
+                return format_text($description, $grouping->descriptionformat, ['context' => $context]);
+            });
+
+        // Time created column.
+        $columns[] = (new column(
+            'timecreated',
+            new lang_string('timecreated', 'core_reportbuilder'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TIMESTAMP)
+            ->add_fields("{$groupingsalias}.timecreated")
+            ->set_is_sortable(true)
+            ->set_callback([format::class, 'userdate']);
+
+        // Time modified column.
+        $columns[] = (new column(
+            'timemodified',
+            new lang_string('timemodified', 'core_reportbuilder'),
+            $this->get_entity_name()
+        ))
+            ->add_joins($this->get_joins())
+            ->set_type(column::TYPE_TIMESTAMP)
+            ->add_fields("{$groupingsalias}.timemodified")
+            ->set_is_sortable(true)
+            ->set_callback([format::class, 'userdate']);
+
+        return $columns;
+    }
+
+    /**
+     * Return list of all available filters
+     *
+     * @return filter[]
+     */
+    protected function get_all_filters(): array {
+        $groupingsalias = $this->get_table_alias('groupings');
+
+        // Name filter.
+        $filters[] = (new filter(
+            text::class,
+            'name',
+            new lang_string('name'),
+            $this->get_entity_name(),
+            "{$groupingsalias}.name"
+        ))
+            ->add_joins($this->get_joins());
+
+        // ID number filter.
+        $filters[] = (new filter(
+            text::class,
+            'idnumber',
+            new lang_string('idnumber'),
+            $this->get_entity_name(),
+            "{$groupingsalias}.idnumber"
+        ))
+            ->add_joins($this->get_joins());
+
+        // Time created filter.
+        $filters[] = (new filter(
+            date::class,
+            'timecreated',
+            new lang_string('timecreated', 'core_reportbuilder'),
+            $this->get_entity_name(),
+            "{$groupingsalias}.timecreated"
+        ))
+            ->add_joins($this->get_joins());
+
+        return $filters;
+    }
+}

group/classes/visibility.php

@@ -0,0 +1,181 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Group visibility methods
+ *
+ * @package   core_group
+ * @copyright 2022 onwards Catalyst IT EU {@link https://catalyst-eu.net}
+ * @author    Mark Johnson <mark.johnson@catalyst-eu.net>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core_group;
+
+/**
+ * Group visibility methods.
+ */
+class visibility {
+
+    /**
+     * Store the number groups with visibility other than ALL on the course.
+     *
+     * @param int $courseid Course ID to update the cache for.
+     * @param \cache|null $cache Existing cache instance. If null, once will be created.
+     * @return void
+     * @throws \dml_exception
+     */
+    public static function update_hiddengroups_cache(int $courseid, ?\cache $cache = null): void {
+        global $DB;
+        if (!$cache) {
+            $cache = \cache::make('core', 'coursehiddengroups');
+        }
+        $hiddengroups = $DB->count_records_select('groups', 'courseid = ? AND visibility != ?',
+                [$courseid, GROUPS_VISIBILITY_ALL]);
+        $cache->set($courseid, $hiddengroups);
+    }
+
+    /**
+     * Return whether a course currently had hidden groups.
+     *
+     * This can be used as a shortcut to decide whether visibility restrictions need to be applied. If this returns false,
+     * we may be able to use cached data, or do a much simpler query.
+     *
+     * @param int $courseid
+     * @return bool
+     * @throws \coding_exception
+     * @throws \dml_exception
+     */
+    public static function course_has_hidden_groups(int $courseid): bool {
+        $cache = \cache::make('core', 'coursehiddengroups');
+        $hiddengroups = $cache->get($courseid);
+        if ($hiddengroups === false) {
+            self::update_hiddengroups_cache($courseid, $cache);
+            $cache->get($courseid);
+        }
+        return $hiddengroups > 0;
+    }
+
+    /**
+     * Can the current user view all the groups on the course?
+     *
+     * Returns true if there are no groups on the course with visibility != ALL,
+     * or if the user has viewhiddengroups.
+     *
+     * This is useful for deciding whether we need to perform additional visibility checkes
+     * such as the sql_* methods of this class.
+     *
+     * @param int $courseid
+     * @return bool
+     */
+    public static function can_view_all_groups(int $courseid): bool {
+        $viewhidden = has_capability('moodle/course:viewhiddengroups', \context_course::instance($courseid));
+        $hashidden = self::course_has_hidden_groups($courseid);
+        return $viewhidden || !$hashidden;
+    }
+
+    /**
+     * Return SQL conditions for determining whether a user can see a group and its memberships.
+     *
+     * @param int $userid
+     * @param string $groupsalias The SQL alias being used for the groups table.
+     * @param string $groupsmembersalias The SQL alias being used for the groups_members table.
+     * @return array [$where, $params]
+     */
+    public static function sql_group_visibility_where(int $userid,
+            string $groupsalias = 'g', string $groupsmembersalias = 'gm'): array {
+        global $USER;
+        // Apply visibility restrictions.
+        // Everyone can see who is in groups with ALL visibility.
+        $where = "({$groupsalias}.visibility = :all";
+        $params['all'] = GROUPS_VISIBILITY_ALL;
+        if ($userid == $USER->id) {
+            // If the user is looking at their own groups, they can see those with MEMBERS or OWN visibility.
+            $where .= " OR {$groupsalias}.visibility IN (:members, :own)";
+            $params['members'] = GROUPS_VISIBILITY_MEMBERS;
+            $params['own'] = GROUPS_VISIBILITY_OWN;
+        } else {
+            list($memberssql, $membersparams) = self::sql_members_visibility_condition($groupsalias, $groupsmembersalias);
+            // If someone else's groups, they can see those with MEMBERS visibilty, only if they are a member too.
+            $where .= " OR ($memberssql)";
+            $params = array_merge($params, $membersparams);
+        }
+        $where .= ")";
+        return [$where, $params];
+    }
+
+    /**
+     * Return SQL conditions for determining whether a user can see a group's members.
+     *
+     * @param string $groupsalias The SQL alias being used for the groups table.
+     * @param string $groupsmembersalias The SQL alias being used for the groups_members table.
+     * @param string $useralias The SQL alias being used for the user table.
+     * @param string $paramprefix Prefix for the parameter names.
+     * @return array [$where, $params]
+     */
+    public static function sql_member_visibility_where(
+        string $groupsalias = 'g',
+        string $groupsmembersalias = 'gm',
+        string $useralias = 'u',
+        string $paramprefix = '',
+    ): array {
+        global $USER;
+
+        list($memberssql, $membersparams) = self::sql_members_visibility_condition($groupsalias, $groupsmembersalias, $paramprefix);
+
+        $where = "(
+            {$groupsalias}.visibility = :{$paramprefix}all
+            OR ($memberssql)
+            OR ({$groupsalias}.visibility = :{$paramprefix}own AND {$useralias}.id = :{$paramprefix}currentuser2)
+        )";
+        $params = [
+            "{$paramprefix}all" => GROUPS_VISIBILITY_ALL,
+            "{$paramprefix}own" => GROUPS_VISIBILITY_OWN,
+            "{$paramprefix}currentuser2" => $USER->id,
+        ];
+        $params = array_merge($params, $membersparams);
+        return [$where, $params];
+    }
+
+    /**
+     * Return a condition to check if a user can view a group because it has MEMBERS visibility and they are a member.
+     *
+     * @param string $groupsalias The SQL alias being used for the groups table.
+     * @param string $groupsmembersalias The SQL alias being used for the groups_members table.
+     * @param string $paramprefix Prefix for the parameter names.
+     * @return array [$sql, $params]
+     */
+    protected static function sql_members_visibility_condition(
+        string $groupsalias = 'g',
+        string $groupsmembersalias = 'gm',
+        string $paramprefix = '',
+    ): array {
+        global $USER;
+        $sql = "{$groupsalias}.visibility = :{$paramprefix}members
+                    AND (
+                        SELECT gm2.id
+                          FROM {groups_members} gm2
+                         WHERE gm2.groupid = {$groupsmembersalias}.groupid
+                               AND gm2.userid = :{$paramprefix}currentuser
+                    ) IS NOT NULL";
+        $params = [
+            "{$paramprefix}members" => GROUPS_VISIBILITY_MEMBERS,
+            "{$paramprefix}currentuser" => $USER->id
+        ];
+
+        return [$sql, $params];
+    }
+}

group/clientlib.js

@@ -0,0 +1,265 @@
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Client-side JavaScript for group management interface.
+ * @copyright vy-shane AT moodle.com
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core_group
+ */
+
+
+/**
+ * Class UpdatableGroupsCombo
+ */
+function UpdatableGroupsCombo(wwwRoot, courseId) {
+    this.wwwRoot = wwwRoot;
+    this.courseId = courseId;
+
+    this.connectCallback = {
+
+        success: function(o) {
+            if (o.responseText !== undefined) {
+                var groupsComboEl = document.getElementById("groups");
+                var membersComboEl = document.getElementById("members");
+                if (membersComboEl) {
+                    // Clear the members list box.
+                    while (membersComboEl.firstChild) {
+                        membersComboEl.removeChild(membersComboEl.firstChild);
+                    }
+                }
+
+                if (groupsComboEl && o.responseText) {
+                    var groups = eval("("+o.responseText+")");
+
+                    // Populate the groups list box.
+                    for (var i=0; i<groups.length; i++) {
+                        var optionEl = document.createElement("option");
+                        optionEl.setAttribute("value", groups[i].id);
+                        optionEl.title = groups[i].name;
+                        optionEl.innerHTML = groups[i].name;
+                        groupsComboEl.appendChild(optionEl);
+                    }
+                }
+            }
+            // Remove the loader gif image.
+            removeLoaderImgs("groupsloader", "groupslabel");
+        },
+
+        failure: function(o) {
+            removeLoaderImgs("membersloader", "memberslabel");
+            this.currentTransId = null;
+        }
+
+    };
+}
+
+
+/**
+ * Class UpdatableMembersCombo
+ */
+function UpdatableMembersCombo(wwwRoot, courseId) {
+    this.wwwRoot = wwwRoot;
+    this.courseId = courseId;
+
+    this.connectCallback = {
+        success: function(t, o) {
+
+            if (o.responseText !== undefined) {
+                var selectEl = document.getElementById("members");
+                if (selectEl && o.responseText) {
+                    var roles = eval("("+o.responseText+")");
+
+                    // Clear the members list box.
+                    if (selectEl) {
+                        while (selectEl.firstChild) {
+                            selectEl.removeChild(selectEl.firstChild);
+                        }
+                    }
+                    // Populate the members list box.
+                    for (var i=0; i<roles.length; i++) {
+                        var optgroupEl = document.createElement("optgroup");
+                        optgroupEl.setAttribute("label",roles[i].name);
+
+                        for(var j=0; j<roles[i].users.length; j++) {
+                            var optionEl = document.createElement("option");
+                            optionEl.setAttribute("value", roles[i].users[j].id);
+                            optionEl.title = roles[i].users[j].name;
+                            optionEl.innerHTML = Y.Escape.html(roles[i].users[j].name);
+                            optgroupEl.appendChild(optionEl);
+                        }
+                        selectEl.appendChild(optgroupEl);
+                    }
+                }
+            }
+            // Remove the loader gif image.
+            removeLoaderImgs("membersloader", "memberslabel");
+        },
+
+        failure: function() {
+            removeLoaderImgs("membersloader", "memberslabel");
+        }
+
+    };
+
+    // Hide the updatemembers input since AJAX will take care of this.
+    var updatemembers = Y.one('#updatemembers');
+    if (updatemembers) {
+        updatemembers.hide();
+    }
+}
+
+/**
+ * When a group is selected, we need to update the members.
+ * The Add/Remove Users button also needs to be disabled/enabled
+ * depending on whether or not a group is selected
+ */
+UpdatableMembersCombo.prototype.refreshMembers = function () {
+
+    // Get group selector and check selection type
+    var selectEl = document.getElementById("groups");
+    var selectionCount=0,groupId=0;
+    if( selectEl ) {
+        for (var i = 0; i < selectEl.options.length; i++) {
+            if(selectEl.options[i].selected) {
+                selectionCount++;
+                if(!groupId) {
+                    groupId=selectEl.options[i].value;
+                }
+            }
+        }
+    }
+    var singleSelection=selectionCount == 1;
+
+    // Add the loader gif image (we only load for single selections)
+    if(singleSelection) {
+        createLoaderImg("membersloader", "memberslabel", this.wwwRoot);
+    }
+
+    // Update the label.
+    var spanEl = document.getElementById("thegroup");
+    if (singleSelection) {
+        spanEl.innerHTML = selectEl.options[selectEl.selectedIndex].title;
+    } else {
+        spanEl.innerHTML = '&nbsp;';
+    }
+
+    // Clear the members list box.
+    selectEl = document.getElementById("members");
+    if (selectEl) {
+        while (selectEl.firstChild) {
+            selectEl.removeChild(selectEl.firstChild);
+        }
+    }
+
+    document.getElementById("showaddmembersform").disabled = !singleSelection;
+    document.getElementById("showeditgroupsettingsform").disabled = !singleSelection;
+    document.getElementById("deletegroup").disabled = selectionCount == 0;
+
+    if(singleSelection) {
+        var sUrl = this.wwwRoot + "/group/index.php?id=" + this.courseId + "&group=" + groupId + "&action=ajax_getmembersingroup";
+        var self = this;
+        YUI().use('io', function (Y) {
+            Y.io(sUrl, {
+                method: 'GET',
+                context: this,
+                on: self.connectCallback
+            });
+        });
+    }
+};
+
+
+
+var createLoaderImg = function (elClass, parentId, wwwRoot) {
+    var parentEl = document.getElementById(parentId);
+    if (!parentEl) {
+        return false;
+    }
+    if (document.getElementById("loaderImg")) {
+        // A loader image already exists.
+        return false;
+    }
+    var loadingImg = document.createElement("img");
+
+    loadingImg.setAttribute("src", M.util.image_url('/i/ajaxloader', 'moodle'));
+    loadingImg.setAttribute("class", elClass);
+    loadingImg.setAttribute("alt", "Loading");
+    loadingImg.setAttribute("id", "loaderImg");
+    parentEl.appendChild(loadingImg);
+
+    return true;
+};
+
+
+var removeLoaderImgs = function (elClass, parentId) {
+    var parentEl = document.getElementById(parentId);
+    if (parentEl) {
+        var loader = document.getElementById("loaderImg");
+        if (loader) {
+            parentEl.removeChild(loader);
+        }
+    }
+};
+
+/**
+ * Updates the current groups information shown about a user when a user is selected.
+ *
+ * @global {Array} userSummaries
+ *      userSummaries is added to the page via /user/selector/lib.php - group_non_members_selector::print_user_summaries()
+ *      as a global that can be used by this function.
+ */
+function updateUserSummary() {
+    var selectEl = document.getElementById('addselect'),
+        summaryDiv = document.getElementById('group-usersummary'),
+        length = selectEl.length,
+        selectCnt = 0,
+        selectIdx = -1,
+        i;
+
+    for (i = 0; i < length; i++) {
+        if (selectEl.options[i].selected) {
+            selectCnt++;
+            selectIdx = i;
+        }
+    }
+
+    if (selectCnt == 1 && userSummaries[selectIdx]) {
+        summaryDiv.innerHTML = userSummaries[selectIdx];
+    } else {
+        summaryDiv.innerHTML = '';
+    }
+
+    return true;
+}
+
+function init_add_remove_members_page(Y) {
+    var add = Y.one('#add');
+    var addselect = M.core_user.get_user_selector('addselect');
+    add.set('disabled', addselect.is_selection_empty());
+    addselect.on('user_selector:selectionchanged', function(isempty) {
+        add.set('disabled', isempty);
+    });
+
+    var remove = Y.one('#remove');
+    var removeselect = M.core_user.get_user_selector('removeselect');
+    remove.set('disabled', removeselect.is_selection_empty());
+    removeselect.on('user_selector:selectionchanged', function(isempty) {
+        remove.set('disabled', isempty);
+    });
+
+    addselect = document.getElementById('addselect');
+    addselect.onchange = updateUserSummary;
+}

group/customfield.php

@@ -0,0 +1,41 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Manage group custom fields
+ *
+ * @package   core_group
+ * @author    Tomo Tsuyuki <tomotsuyuki@catalyst-au.net>
+ * @copyright 2023 Catalyst IT Pty Ltd
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+use core_group\customfield\group_handler;
+use core_customfield\output\management;
+
+require_once('../config.php');
+require_once($CFG->libdir . '/adminlib.php');
+
+admin_externalpage_setup('group_customfield');
+
+$output = $PAGE->get_renderer('core_customfield');
+$handler = group_handler::create();
+$outputpage = new management($handler);
+
+echo $output->header(),
+     $output->heading(new lang_string('group_customfield', 'admin')),
+     $output->render($outputpage),
+     $output->footer();

group/delete.php

@@ -0,0 +1,97 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * Delete group
+ *
+ * @package   core_group
+ * @copyright 2008 The Open University, s.marshall AT open.ac.uk
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+require_once('../config.php');
+require_once('lib.php');
+
+// Get and check parameters
+$courseid = required_param('courseid', PARAM_INT);
+$groupids = required_param('groups', PARAM_SEQUENCE);
+$confirm = optional_param('confirm', 0, PARAM_BOOL);
+
+$PAGE->set_url('/group/delete.php', array('courseid'=>$courseid,'groups'=>$groupids));
+$PAGE->set_pagelayout('standard');
+
+// Make sure course is OK and user has access to manage groups
+if (!$course = $DB->get_record('course', array('id' => $courseid))) {
+    throw new \moodle_exception('invalidcourseid');
+}
+require_login($course);
+$context = context_course::instance($course->id);
+require_capability('moodle/course:managegroups', $context);
+$changeidnumber = has_capability('moodle/course:changeidnumber', $context);
+
+// Make sure all groups are OK and belong to course
+$groupidarray = explode(',',$groupids);
+$groupnames = array();
+foreach($groupidarray as $groupid) {
+    if (!$group = $DB->get_record('groups', array('id' => $groupid))) {
+        throw new \moodle_exception('invalidgroupid');
+    }
+    if (!empty($group->idnumber) && !$changeidnumber) {
+        throw new \moodle_exception('grouphasidnumber', '', '', $group->name);
+    }
+    if ($courseid != $group->courseid) {
+        throw new \moodle_exception('groupunknown', '', '', $group->courseid);
+    }
+    $groupnames[] = format_string($group->name);
+}
+
+$returnurl='index.php?id='.$course->id;
+
+if(count($groupidarray)==0) {
+    throw new \moodle_exception('errorselectsome', 'group', $returnurl);
+}
+
+if ($confirm && data_submitted()) {
+    if (!confirm_sesskey() ) {
+        throw new \moodle_exception('confirmsesskeybad', 'error', $returnurl);
+    }
+
+    foreach($groupidarray as $groupid) {
+        groups_delete_group($groupid);
+    }
+
+    redirect($returnurl);
+} else {
+    $PAGE->set_title(get_string('deleteselectedgroup', 'group'));
+    $PAGE->set_heading($course->fullname . ': '. get_string('deleteselectedgroup', 'group'));
+    echo $OUTPUT->header();
+    $optionsyes = array('courseid'=>$courseid, 'groups'=>$groupids, 'sesskey'=>sesskey(), 'confirm'=>1);
+    $optionsno = array('id'=>$courseid);
+    if(count($groupnames)==1) {
+        $message=get_string('deletegroupconfirm', 'group', $groupnames[0]);
+    } else {
+        $message=get_string('deletegroupsconfirm', 'group').'<ul>';
+        foreach($groupnames as $groupname) {
+            $message.='<li>'.$groupname.'</li>';
+        }
+        $message.='</ul>';
+    }
+    $formcontinue = new single_button(new moodle_url('delete.php', $optionsyes), get_string('yes'), 'post');
+    $formcancel = new single_button(new moodle_url('index.php', $optionsno), get_string('no'), 'get');
+    echo $OUTPUT->confirm($message, $formcontinue, $formcancel);
+    echo $OUTPUT->footer();
+}

group/group.php

@@ -0,0 +1,139 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * Create group OR edit group settings.
+ *
+ * @copyright 2006 The Open University, N.D.Freear AT open.ac.uk, J.White AT open.ac.uk
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+
+require_once('../config.php');
+require_once('lib.php');
+require_once('group_form.php');
+
+/// get url variables
+$courseid = optional_param('courseid', 0, PARAM_INT);
+$id       = optional_param('id', 0, PARAM_INT);
+$delete   = optional_param('delete', 0, PARAM_BOOL);
+$confirm  = optional_param('confirm', 0, PARAM_BOOL);
+
+// This script used to support group delete, but that has been moved. In case
+// anyone still links to it, let's redirect to the new script.
+if ($delete) {
+    debugging('Deleting a group through group/group.php is deprecated and will be removed soon. Please use group/delete.php instead');
+    redirect(new moodle_url('delete.php', array('courseid' => $courseid, 'groups' => $id)));
+}
+
+
+if ($id) {
+    if (!$group = $DB->get_record('groups', array('id'=>$id))) {
+        throw new \moodle_exception('invalidgroupid');
+    }
+    if (empty($courseid)) {
+        $courseid = $group->courseid;
+
+    } else if ($courseid != $group->courseid) {
+        throw new \moodle_exception('invalidcourseid');
+    }
+
+    if (!$course = $DB->get_record('course', array('id'=>$courseid))) {
+        throw new \moodle_exception('invalidcourseid');
+    }
+
+} else {
+    if (!$course = $DB->get_record('course', array('id'=>$courseid))) {
+        throw new \moodle_exception('invalidcourseid');
+    }
+    $group = new stdClass();
+    $group->courseid = $course->id;
+}
+
+if ($id !== 0) {
+    $PAGE->set_url('/group/group.php', array('id'=>$id));
+} else {
+    $PAGE->set_url('/group/group.php', array('courseid'=>$courseid));
+}
+
+require_login($course);
+$context = context_course::instance($course->id);
+require_capability('moodle/course:managegroups', $context);
+
+$strgroups = get_string('groups');
+$PAGE->set_title($strgroups);
+$PAGE->set_heading($course->fullname . ': '.$strgroups);
+$PAGE->set_pagelayout('admin');
+navigation_node::override_active_url(new moodle_url('/group/index.php', array('id' => $course->id)));
+
+$returnurl = $CFG->wwwroot.'/group/index.php?id='.$course->id.'&group='.$id;
+
+// Prepare the description editor: We do support files for group descriptions
+$editoroptions = array('maxfiles'=>EDITOR_UNLIMITED_FILES, 'maxbytes'=>$course->maxbytes, 'trust'=>false, 'context'=>$context, 'noclean'=>true);
+if (!empty($group->id)) {
+    $editoroptions['subdirs'] = file_area_contains_subdirs($context, 'group', 'description', $group->id);
+    $group = file_prepare_standard_editor($group, 'description', $editoroptions, $context, 'group', 'description', $group->id);
+} else {
+    $editoroptions['subdirs'] = false;
+    $group = file_prepare_standard_editor($group, 'description', $editoroptions, $context, 'group', 'description', null);
+}
+
+/// First create the form
+$editform = new group_form(null, array('editoroptions' => $editoroptions, 'group' => $group));
+$editform->set_data($group);
+
+if ($editform->is_cancelled()) {
+    redirect($returnurl);
+
+} elseif ($data = $editform->get_data()) {
+    if (!has_capability('moodle/course:changeidnumber', $context)) {
+        // Remove the idnumber if the user doesn't have permission to modify it
+        unset($data->idnumber);
+    }
+
+    if ($data->id) {
+        groups_update_group($data, $editform, $editoroptions);
+    } else {
+        $id = groups_create_group($data, $editform, $editoroptions);
+        $returnurl = $CFG->wwwroot.'/group/index.php?id='.$course->id.'&group='.$id;
+    }
+
+    redirect($returnurl);
+}
+
+$strgroups = get_string('groups');
+$strparticipants = get_string('participants');
+
+if ($id) {
+    $strheading = get_string('editgroupsettings', 'group');
+} else {
+    $strheading = get_string('creategroup', 'group');
+}
+
+$PAGE->navbar->add($strparticipants, new moodle_url('/user/index.php', array('id'=>$courseid)));
+$PAGE->navbar->add($strgroups, new moodle_url('/group/index.php', array('id'=>$courseid)));
+$PAGE->navbar->add($strheading);
+
+/// Print header
+echo $OUTPUT->header();
+echo '<div id="grouppicture">';
+if ($id) {
+    print_group_picture($group, $course->id);
+}
+echo '</div>';
+$editform->display();
+echo $OUTPUT->footer();

group/group_form.php

@@ -0,0 +1,240 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * A form for the creation and editing of groups.
+ *
+ * @copyright 2006 The Open University, N.D.Freear AT open.ac.uk, J.White AT open.ac.uk
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+
+defined('MOODLE_INTERNAL') || die;
+
+use core_group\visibility;
+
+require_once($CFG->dirroot.'/lib/formslib.php');
+
+/**
+ * Group form class
+ *
+ * @copyright 2006 The Open University, N.D.Freear AT open.ac.uk, J.White AT open.ac.uk
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+class group_form extends moodleform {
+
+    /**
+     * Definition of the form
+     */
+    function definition() {
+        global $USER, $CFG, $COURSE;
+        $coursecontext = context_course::instance($COURSE->id);
+
+        $mform =& $this->_form;
+        $editoroptions = $this->_customdata['editoroptions'];
+        $group = $this->_customdata['group'];
+
+        $mform->addElement('header', 'general', get_string('general', 'form'));
+
+        $mform->addElement('text','name', get_string('groupname', 'group'),'maxlength="254" size="50"');
+        $mform->addRule('name', get_string('required'), 'required', null, 'client');
+        $mform->setType('name', PARAM_TEXT);
+
+        $mform->addElement('text','idnumber', get_string('idnumbergroup'), 'maxlength="100" size="10"');
+        $mform->addHelpButton('idnumber', 'idnumbergroup');
+        $mform->setType('idnumber', PARAM_RAW);
+        if (!has_capability('moodle/course:changeidnumber', $coursecontext)) {
+            $mform->hardFreeze('idnumber');
+        }
+
+        $mform->addElement('editor', 'description_editor', get_string('groupdescription', 'group'), null, $editoroptions);
+        $mform->setType('description_editor', PARAM_RAW);
+
+        $mform->addElement('passwordunmask', 'enrolmentkey', get_string('enrolmentkey', 'group'), 'maxlength="254" size="24"', get_string('enrolmentkey', 'group'));
+        $mform->addHelpButton('enrolmentkey', 'enrolmentkey', 'group');
+        $mform->setType('enrolmentkey', PARAM_RAW);
+
+        $visibilityoptions = [
+            GROUPS_VISIBILITY_ALL => get_string('visibilityall', 'group'),
+            GROUPS_VISIBILITY_MEMBERS => get_string('visibilitymembers', 'group'),
+            GROUPS_VISIBILITY_OWN => get_string('visibilityown', 'group'),
+            GROUPS_VISIBILITY_NONE => get_string('visibilitynone', 'group')
+        ];
+        $mform->addElement('select', 'visibility', get_string('visibility', 'group'), $visibilityoptions);
+        $mform->addHelpButton('visibility', 'visibility', 'group');
+        $mform->setType('visibility', PARAM_INT);
+
+        $mform->addElement('advcheckbox', 'participation', '', get_string('participation', 'group'));
+        $mform->addHelpButton('participation', 'participation', 'group');
+        $mform->setType('participation', PARAM_BOOL);
+        $mform->setDefault('participation', 1);
+        $mform->hideIf('participation', 'visibility', 'in', [GROUPS_VISIBILITY_OWN, GROUPS_VISIBILITY_NONE]);
+
+        // Group conversation messaging.
+        if (\core_message\api::can_create_group_conversation($USER->id, $coursecontext)) {
+            $mform->addElement('selectyesno', 'enablemessaging', get_string('enablemessaging', 'group'));
+            $mform->addHelpButton('enablemessaging', 'enablemessaging', 'group');
+            $mform->hideIf('enablemessaging', 'visibility', 'in', [GROUPS_VISIBILITY_OWN, GROUPS_VISIBILITY_NONE]);
+        }
+
+        $mform->addElement('static', 'currentpicture', get_string('currentpicture'));
+
+        $mform->addElement('checkbox', 'deletepicture', get_string('delete'));
+        $mform->setDefault('deletepicture', 0);
+
+        $mform->addElement('filepicker', 'imagefile', get_string('newpicture', 'group'));
+        $mform->addHelpButton('imagefile', 'newpicture', 'group');
+
+        $handler = \core_group\customfield\group_handler::create();
+        $handler->instance_form_definition($mform, empty($group->id) ? 0 : $group->id);
+        $handler->instance_form_before_set_data($group);
+
+        $mform->addElement('hidden','id');
+        $mform->setType('id', PARAM_INT);
+
+        $mform->addElement('hidden','courseid');
+        $mform->setType('courseid', PARAM_INT);
+
+        $this->add_action_buttons();
+    }
+
+    /**
+     * Extend the form definition after the data has been parsed.
+     */
+    public function definition_after_data() {
+        global $COURSE, $DB, $USER;
+
+        $mform = $this->_form;
+        $groupid = $mform->getElementValue('id');
+        $coursecontext = context_course::instance($COURSE->id);
+
+        if ($group = $DB->get_record('groups', array('id' => $groupid))) {
+            // If can create group conversation then get if a conversation area exists and it is enabled.
+            if (\core_message\api::can_create_group_conversation($USER->id, $coursecontext)) {
+                if (\core_message\api::is_conversation_area_enabled('core_group', 'groups', $groupid, $coursecontext->id)) {
+                    $mform->getElement('enablemessaging')->setSelected(1);
+                }
+            }
+            // Print picture.
+            if (!($pic = print_group_picture($group, $COURSE->id, true, true, false))) {
+                $pic = get_string('none');
+                if ($mform->elementExists('deletepicture')) {
+                    $mform->removeElement('deletepicture');
+                }
+            }
+            $imageelement = $mform->getElement('currentpicture');
+            $imageelement->setValue($pic);
+        } else {
+            if ($mform->elementExists('currentpicture')) {
+                $mform->removeElement('currentpicture');
+            }
+            if ($mform->elementExists('deletepicture')) {
+                $mform->removeElement('deletepicture');
+            }
+        }
+
+        if ($DB->record_exists('groups_members', ['groupid' => $groupid])) {
+            // If the group has members, lock visibility and participation fields.
+            /** @var MoodleQuickForm_select $visibility */
+            $visibility = $mform->getElement('visibility');
+            $visibility->freeze();
+            /** @var MoodleQuickForm_advcheckbox $participation */
+            $participation = $mform->getElement('participation');
+            $participation->freeze();
+        }
+
+        $handler = core_group\customfield\group_handler::create();
+        $handler->instance_form_definition_after_data($this->_form, empty($groupid) ? 0 : $groupid);
+    }
+
+    /**
+     * Form validation
+     *
+     * @param array $data
+     * @param array $files
+     * @return array $errors An array of errors
+     */
+    function validation($data, $files) {
+        global $COURSE, $DB, $CFG;
+
+        $errors = parent::validation($data, $files);
+
+        $name = trim($data['name']);
+        if (isset($data['idnumber'])) {
+            $idnumber = trim($data['idnumber']);
+        } else {
+            $idnumber = '';
+        }
+        if ($data['id'] && $group = $DB->get_record('groups', ['id' => $data['id']])) {
+            if ($group->name != $name) {
+                if (groups_get_group_by_name($COURSE->id,  $name)) {
+                    $errors['name'] = get_string('groupnameexists', 'group', $name);
+                }
+            }
+            if (!empty($idnumber) && $group->idnumber != $idnumber) {
+                if (groups_get_group_by_idnumber($COURSE->id, $idnumber)) {
+                    $errors['idnumber']= get_string('idnumbertaken');
+                }
+            }
+
+            if ($data['enrolmentkey'] != '') {
+                $errmsg = '';
+                if (!empty($CFG->groupenrolmentkeypolicy) && $group->enrolmentkey !== $data['enrolmentkey']
+                        && !check_password_policy($data['enrolmentkey'], $errmsg)) {
+                    // Enforce password policy when the password is changed.
+                    $errors['enrolmentkey'] = $errmsg;
+                } else {
+                    // Prevent twice the same enrolment key in course groups.
+                    $sql = "SELECT id FROM {groups} WHERE id <> :groupid AND courseid = :courseid AND enrolmentkey = :key";
+                    $params = array('groupid' => $data['id'], 'courseid' => $COURSE->id, 'key' => $data['enrolmentkey']);
+                    if ($DB->record_exists_sql($sql, $params)) {
+                        $errors['enrolmentkey'] = get_string('enrolmentkeyalreadyinuse', 'group');
+                    }
+                }
+            }
+
+        } else if (groups_get_group_by_name($COURSE->id, $name)) {
+            $errors['name'] = get_string('groupnameexists', 'group', $name);
+        } else if (!empty($idnumber) && groups_get_group_by_idnumber($COURSE->id, $idnumber)) {
+            $errors['idnumber']= get_string('idnumbertaken');
+        } else if ($data['enrolmentkey'] != '') {
+            $errmsg = '';
+            if (!empty($CFG->groupenrolmentkeypolicy) && !check_password_policy($data['enrolmentkey'], $errmsg)) {
+                // Enforce password policy.
+                $errors['enrolmentkey'] = $errmsg;
+            } else if ($DB->record_exists('groups', array('courseid' => $COURSE->id, 'enrolmentkey' => $data['enrolmentkey']))) {
+                // Prevent the same enrolment key from being used multiple times in course groups.
+                $errors['enrolmentkey'] = get_string('enrolmentkeyalreadyinuse', 'group');
+            }
+        }
+
+        $handler = \core_group\customfield\group_handler::create();
+        $errors = array_merge($errors, $handler->instance_form_validation($data, $files));
+
+        return $errors;
+    }
+
+    /**
+     * Get editor options for this form
+     *
+     * @return array An array of options
+     */
+    function get_editor_options() {
+        return $this->_customdata['editoroptions'];
+    }
+}

group/grouping.php

@@ -0,0 +1,149 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * Create grouping OR edit grouping settings.
+ *
+ * @copyright 2006 The Open University, N.D.Freear AT open.ac.uk, J.White AT open.ac.uk
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+require_once('../config.php');
+require_once('lib.php');
+require_once('grouping_form.php');
+
+/// get url variables
+$courseid = optional_param('courseid', 0, PARAM_INT);
+$id       = optional_param('id', 0, PARAM_INT);
+$delete   = optional_param('delete', 0, PARAM_BOOL);
+$confirm  = optional_param('confirm', 0, PARAM_BOOL);
+
+$url = new moodle_url('/group/grouping.php');
+if ($id) {
+    $url->param('id', $id);
+    if (!$grouping = $DB->get_record('groupings', array('id'=>$id))) {
+        throw new \moodle_exception('invalidgroupid');
+    }
+    $grouping->description = clean_text($grouping->description);
+    if (empty($courseid)) {
+        $courseid = $grouping->courseid;
+    } else if ($courseid != $grouping->courseid) {
+        throw new \moodle_exception('invalidcourseid');
+    } else {
+        $url->param('courseid', $courseid);
+    }
+
+    if (!$course = $DB->get_record('course', array('id'=>$courseid))) {
+        throw new \moodle_exception('invalidcourseid');
+    }
+
+} else {
+    $url->param('courseid', $courseid);
+    if (!$course = $DB->get_record('course', array('id'=>$courseid))) {
+        throw new \moodle_exception('invalidcourseid');
+    }
+    $grouping = new stdClass();
+    $grouping->courseid = $course->id;
+}
+
+$PAGE->set_url($url);
+
+require_login($course);
+$context = context_course::instance($course->id);
+require_capability('moodle/course:managegroups', $context);
+
+$strgroupings = get_string('groupings', 'group');
+$PAGE->set_title($strgroupings);
+$PAGE->set_heading($course->fullname. ': '.$strgroupings);
+$PAGE->set_pagelayout('admin');
+navigation_node::override_active_url(new moodle_url('/group/index.php', array('id' => $course->id)));
+
+$returnurl = $CFG->wwwroot.'/group/groupings.php?id='.$course->id;
+
+if ($id and $delete) {
+    if (!empty($grouping->idnumber) && !has_capability('moodle/course:changeidnumber', $context)) {
+        throw new \moodle_exception('groupinghasidnumber', '', '', $grouping->name);
+    }
+    if (!$confirm) {
+        $PAGE->set_title(get_string('deletegrouping', 'group'));
+        $PAGE->set_heading($course->fullname. ': '. get_string('deletegrouping', 'group'));
+        echo $OUTPUT->header();
+        $optionsyes = array('id'=>$id, 'delete'=>1, 'courseid'=>$courseid, 'sesskey'=>sesskey(), 'confirm'=>1);
+        $optionsno  = array('id'=>$courseid);
+        $formcontinue = new single_button(new moodle_url('grouping.php', $optionsyes), get_string('yes'), 'get');
+        $formcancel = new single_button(new moodle_url('groupings.php', $optionsno), get_string('no'), 'get');
+        echo $OUTPUT->confirm(get_string('deletegroupingconfirm', 'group', $grouping->name), $formcontinue, $formcancel);
+        echo $OUTPUT->footer();
+        die;
+
+    } else if (confirm_sesskey()){
+        if (groups_delete_grouping($id)) {
+            redirect($returnurl);
+        } else {
+            throw new \moodle_exception('erroreditgrouping', 'group', $returnurl);
+        }
+    }
+}
+
+// Prepare the description editor: We do support files for grouping descriptions
+$editoroptions = array('maxfiles'=>EDITOR_UNLIMITED_FILES, 'maxbytes'=>$course->maxbytes, 'trust'=>true, 'context'=>$context, 'noclean'=>true);
+if (!empty($grouping->id)) {
+    $grouping = file_prepare_standard_editor($grouping, 'description', $editoroptions, $context, 'grouping', 'description', $grouping->id);
+} else {
+    $grouping = file_prepare_standard_editor($grouping, 'description', $editoroptions, $context, 'grouping', 'description', null);
+}
+
+/// First create the form
+$editform = new grouping_form(null, compact('editoroptions', 'grouping'));
+$editform->set_data($grouping);
+
+if ($editform->is_cancelled()) {
+    redirect($returnurl);
+
+} elseif ($data = $editform->get_data()) {
+    $success = true;
+    if (!has_capability('moodle/course:changeidnumber', $context)) {
+        // Remove the idnumber if the user doesn't have permission to modify it
+        unset($data->idnumber);
+    }
+
+    if ($data->id) {
+        groups_update_grouping($data, $editoroptions);
+    } else {
+        groups_create_grouping($data, $editoroptions);
+    }
+
+    redirect($returnurl);
+
+}
+
+$strparticipants = get_string('participants');
+if ($id) {
+    $strheading = get_string('editgroupingsettings', 'group');
+} else {
+    $strheading = get_string('creategrouping', 'group');
+}
+
+$PAGE->navbar->add($strparticipants, new moodle_url('/user/index.php', array('id'=>$courseid)));
+$PAGE->navbar->add($strgroupings, new moodle_url('/group/groupings.php', array('id'=>$courseid)));
+$PAGE->navbar->add($strheading);
+
+/// Print header
+echo $OUTPUT->header();
+echo $OUTPUT->heading($strheading);
+$editform->display();
+echo $OUTPUT->footer();

group/grouping_customfield.php

@@ -0,0 +1,41 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Manage grouping custom fields
+ *
+ * @package   core_group
+ * @author    Tomo Tsuyuki <tomotsuyuki@catalyst-au.net>
+ * @copyright 2023 Catalyst IT Pty Ltd
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+use core_group\customfield\grouping_handler;
+use core_customfield\output\management;
+
+require_once('../config.php');
+require_once($CFG->libdir . '/adminlib.php');
+
+admin_externalpage_setup('grouping_customfield');
+
+$output = $PAGE->get_renderer('core_customfield');
+$handler = grouping_handler::create();
+$outputpage = new management($handler);
+
+echo $output->header(),
+     $output->heading(new lang_string('grouping_customfield', 'admin')),
+     $output->render($outputpage),
+     $output->footer();

group/grouping_form.php

@@ -0,0 +1,131 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * A form for creating and editing groupings.
+ *
+ * @copyright 2006 The Open University, N.D.Freear AT open.ac.uk, J.White AT open.ac.uk
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+
+if (!defined('MOODLE_INTERNAL')) {
+    die('Direct access to this script is forbidden.');    ///  It must be included from a Moodle page
+}
+
+require_once($CFG->dirroot.'/lib/formslib.php');
+
+/**
+ * Grouping form class
+ *
+ * @copyright 2006 The Open University, N.D.Freear AT open.ac.uk, J.White AT open.ac.uk
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+class grouping_form extends moodleform {
+
+    /**
+     * Form definition
+     */
+    function definition() {
+        global $USER, $CFG, $COURSE;
+        $coursecontext = context_course::instance($COURSE->id);
+
+        $mform =& $this->_form;
+        $editoroptions = $this->_customdata['editoroptions'];
+        $grouping = $this->_customdata['grouping'];
+
+        $mform->addElement('header', 'general', get_string('general', 'form'));
+
+        $mform->addElement('text','name', get_string('groupingname', 'group'),'maxlength="254" size="50"');
+        $mform->addRule('name', get_string('required'), 'required', null, 'server');
+        $mform->setType('name', PARAM_TEXT);
+
+        $mform->addElement('text','idnumber', get_string('idnumbergrouping'), 'maxlength="100" size="10"');
+        $mform->addHelpButton('idnumber', 'idnumbergrouping');
+        $mform->setType('idnumber', PARAM_RAW);
+        if (!has_capability('moodle/course:changeidnumber', $coursecontext)) {
+            $mform->hardFreeze('idnumber');
+        }
+
+        $mform->addElement('editor', 'description_editor', get_string('groupingdescription', 'group'), null, $editoroptions);
+        $mform->setType('description_editor', PARAM_RAW);
+
+        $handler = \core_group\customfield\grouping_handler::create();
+        $handler->instance_form_definition($mform, empty($grouping->id) ? 0 : $grouping->id);
+        $handler->instance_form_before_set_data($grouping);
+
+        $mform->addElement('hidden','id');
+        $mform->setType('id', PARAM_INT);
+
+        $mform->addElement('hidden', 'courseid');
+        $mform->setType('courseid', PARAM_INT);
+
+        $this->add_action_buttons();
+    }
+
+    /**
+     * Form validation
+     *
+     * @param array $data
+     * @param array $files
+     * @return array $errors An array of validataion errors for the form.
+     */
+    function validation($data, $files) {
+        global $COURSE, $DB;
+
+        $errors = parent::validation($data, $files);
+
+        $name = trim($data['name']);
+        if (isset($data['idnumber'])) {
+            $idnumber = trim($data['idnumber']);
+        } else {
+            $idnumber = '';
+        }
+        if ($data['id'] and $grouping = $DB->get_record('groupings', array('id'=>$data['id']))) {
+            if (core_text::strtolower($grouping->name) != core_text::strtolower($name)) {
+                if (groups_get_grouping_by_name($COURSE->id,  $name)) {
+                    $errors['name'] = get_string('groupingnameexists', 'group', $name);
+                }
+            }
+            if (!empty($idnumber) && $grouping->idnumber != $idnumber) {
+                if (groups_get_grouping_by_idnumber($COURSE->id, $idnumber)) {
+                    $errors['idnumber']= get_string('idnumbertaken');
+                }
+            }
+
+        } else if (groups_get_grouping_by_name($COURSE->id, $name)) {
+            $errors['name'] = get_string('groupingnameexists', 'group', $name);
+        } else if (!empty($idnumber) && groups_get_grouping_by_idnumber($COURSE->id, $idnumber)) {
+            $errors['idnumber']= get_string('idnumbertaken');
+        }
+
+        $handler = \core_group\customfield\grouping_handler::create();
+        $errors = array_merge($errors, $handler->instance_form_validation($data, $files));
+
+        return $errors;
+    }
+
+    /**
+     *  Apply a logic after data is set.
+     */
+    public function definition_after_data() {
+        $groupid = $this->_form->getElementValue('id');
+        $handler = \core_group\customfield\grouping_handler::create();
+        $handler->instance_form_definition_after_data($this->_form, empty($groupid) ? 0 : $groupid);
+    }
+}

group/groupings.php

@@ -0,0 +1,117 @@
+<?php
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Allows a creator to edit groupings
+ *
+ * @copyright 1999 Martin Dougiamas  http://dougiamas.com
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core_group
+ */
+
+require_once '../config.php';
+require_once $CFG->dirroot.'/group/lib.php';
+
+$courseid = required_param('id', PARAM_INT);
+
+$PAGE->set_url('/group/groupings.php', array('id'=>$courseid));
+
+if (!$course = $DB->get_record('course', array('id'=>$courseid))) {
+    throw new \moodle_exception('invalidcourseid');
+}
+
+require_login($course);
+$context = context_course::instance($course->id);
+require_capability('moodle/course:managegroups', $context);
+
+$strgrouping     = get_string('grouping', 'group');
+$strgroups       = get_string('groups');
+$strname         = get_string('name');
+$strdelete       = get_string('delete');
+$stredit         = get_string('edit');
+$srtnewgrouping  = get_string('creategrouping', 'group');
+$strgroups       = get_string('groups');
+$strgroupings    = get_string('groupings', 'group');
+$struses         = get_string('activities');
+$strparticipants = get_string('participants');
+$strmanagegrping = get_string('showgroupsingrouping', 'group');
+
+navigation_node::override_active_url(new moodle_url('/group/index.php', array('id'=>$courseid)));
+$PAGE->navbar->add($strgroupings);
+
+/// Print header
+$PAGE->set_title($strgroupings);
+$PAGE->set_heading($course->fullname);
+$PAGE->set_pagelayout('standard');
+
+echo $OUTPUT->header();
+echo $OUTPUT->render_participants_tertiary_nav($course);
+
+$data = array();
+if ($groupings = $DB->get_records('groupings', array('courseid'=>$course->id), 'name')) {
+    $canchangeidnumber = has_capability('moodle/course:changeidnumber', $context);
+    foreach ($groupings as $gid => $grouping) {
+        $groupings[$gid]->formattedname = format_string($grouping->name, true, array('context' => $context));
+    }
+    core_collator::asort_objects_by_property($groupings, 'formattedname');
+    foreach($groupings as $grouping) {
+        $line = array();
+        $line[0] = $grouping->formattedname;
+
+        if ($groups = groups_get_all_groups($courseid, 0, $grouping->id)) {
+            $groupnames = array();
+            foreach ($groups as $group) {
+                $groupnames[] = format_string($group->name);
+            }
+            $line[1] = implode(', ', $groupnames);
+        } else {
+            $line[1] = get_string('none');
+        }
+        $line[2] = $DB->count_records('course_modules', array('course'=>$course->id, 'groupingid'=>$grouping->id));
+
+        $url = new moodle_url('/group/grouping.php', array('id' => $grouping->id));
+        $buttons  = html_writer::link($url, $OUTPUT->pix_icon('t/edit', $stredit, 'core',
+                array('class' => 'iconsmall')), array('title' => $stredit));
+        if (empty($grouping->idnumber) || $canchangeidnumber) {
+            // It's only possible to delete groups without an idnumber unless the user has the changeidnumber capability.
+            $url = new moodle_url('/group/grouping.php', array('id' => $grouping->id, 'delete' => 1));
+            $buttons .= html_writer::link($url, $OUTPUT->pix_icon('t/delete', $strdelete, 'core',
+                    array('class' => 'iconsmall')), array('title' => $strdelete));
+        } else {
+            $buttons .= $OUTPUT->spacer();
+        }
+        $url = new moodle_url('/group/assign.php', array('id' => $grouping->id));
+        $buttons .= html_writer::link($url, $OUTPUT->pix_icon('t/groups', $strmanagegrping, 'core',
+                array('class' => 'iconsmall')), array('title' => $strmanagegrping));
+
+        $line[3] = $buttons;
+        $data[] = $line;
+    }
+}
+$table = new html_table();
+$table->head  = array($strgrouping, $strgroups, $struses, $stredit);
+$table->size  = array('30%', '50%', '10%', '10%');
+$table->align = array('left', 'left', 'center', 'center');
+$table->width = '90%';
+$table->data  = $data;
+echo html_writer::table($table);
+
+echo $OUTPUT->container_start('buttons');
+echo $OUTPUT->single_button(new moodle_url('grouping.php', array('courseid'=>$courseid)), $srtnewgrouping);
+echo $OUTPUT->container_end();
+
+echo $OUTPUT->footer();

group/import.php

@@ -0,0 +1,271 @@
+<?php
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Bulk group creation registration script from a comma separated file
+ *
+ * @copyright 1999 Martin Dougiamas  http://dougiamas.com
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core_group
+ */
+
+require_once('../config.php');
+require_once($CFG->dirroot.'/course/lib.php');
+require_once($CFG->dirroot.'/group/lib.php');
+include_once('import_form.php');
+
+$id = required_param('id', PARAM_INT);    // Course id
+
+$course = $DB->get_record('course', array('id'=>$id), '*', MUST_EXIST);
+
+$PAGE->set_url('/group/import.php', array('id'=>$id));
+
+require_login($course);
+$context = context_course::instance($id);
+
+require_capability('moodle/course:managegroups', $context);
+
+$strimportgroups = get_string('importgroups', 'core_group');
+
+$PAGE->navbar->add($strimportgroups);
+navigation_node::override_active_url(new moodle_url('/group/index.php', array('id' => $course->id)));
+$PAGE->set_title("$course->shortname: $strimportgroups");
+$PAGE->set_heading($course->fullname);
+$PAGE->set_pagelayout('admin');
+
+$returnurl = new moodle_url('/group/index.php', array('id'=>$id));
+
+$importform = new groups_import_form(null, ['id' => $id]);
+
+// If a file has been uploaded, then process it
+if ($importform->is_cancelled()) {
+    redirect($returnurl);
+
+} else if ($formdata = $importform->get_data()) {
+    echo $OUTPUT->header();
+
+    $text = $importform->get_file_content('userfile');
+    $text = preg_replace('!\r\n?!', "\n", $text);
+
+    require_once($CFG->libdir . '/csvlib.class.php');
+    $importid = csv_import_reader::get_new_iid('groupimport');
+    $csvimport = new csv_import_reader($importid, 'groupimport');
+    $delimiter = $formdata->delimiter_name;
+    $encoding = $formdata->encoding;
+    $readcount = $csvimport->load_csv_content($text, $encoding, $delimiter);
+
+    if ($readcount === false) {
+        throw new \moodle_exception('csvfileerror', 'error', $PAGE->url, $csvimport->get_error());
+    } else if ($readcount == 0) {
+        throw new \moodle_exception('csvemptyfile', 'error', $PAGE->url, $csvimport->get_error());
+    } else if ($readcount == 1) {
+        throw new \moodle_exception('csvnodata', 'error', $PAGE->url);
+    }
+
+    $csvimport->init();
+
+    unset($text);
+
+    // make arrays of valid fields for error checking
+    $required = array("groupname" => 1);
+    $optionaldefaults = array("lang" => 1);
+    $optional = array("coursename" => 1,
+            "idnumber" => 1,
+            "groupidnumber" => 1,
+            "description" => 1,
+            "enrolmentkey" => 1,
+            "groupingname" => 1,
+            "enablemessaging" => 1,
+        );
+    // Check custom fields from group and grouping.
+    $customfields = \core_group\customfield\group_handler::create()->get_fields();
+    $customfieldnames = [];
+    foreach ($customfields as $customfield) {
+        $controller = \core_customfield\data_controller::create(0, null, $customfield);
+        $customfieldnames['customfield_' . $customfield->get('shortname')] = 1;
+    }
+    $customfields = \core_group\customfield\grouping_handler::create()->get_fields();
+    $groupingcustomfields = [];
+    foreach ($customfields as $customfield) {
+        $controller = \core_customfield\data_controller::create(0, null, $customfield);
+        $groupingcustomfieldname = 'grouping_customfield_' . $customfield->get('shortname');
+        $customfieldnames[$groupingcustomfieldname] = 1;
+        $groupingcustomfields[$groupingcustomfieldname] = 'customfield_' . $customfield->get('shortname');
+    }
+
+    // --- get header (field names) ---
+    // Using get_columns() ensures the Byte Order Mark is removed.
+    $header = $csvimport->get_columns();
+
+    // Check for valid field names.
+    foreach ($header as $i => $h) {
+        // Remove whitespace.
+        $h = trim($h);
+        $header[$i] = $h;
+        if (!isset($required[$h]) && !isset($optionaldefaults[$h]) && !isset($optional[$h]) && !isset($customfieldnames[$h])) {
+            throw new \moodle_exception('invalidfieldname', 'error', $PAGE->url, $h);
+        }
+        if (isset($required[$h])) {
+            $required[$h] = 2;
+        }
+    }
+    // check for required fields
+    foreach ($required as $key => $value) {
+        if ($value < 2) {
+            throw new \moodle_exception('fieldrequired', 'error', $PAGE->url, $key);
+        }
+    }
+    $linenum = 2; // since header is line 1
+
+    while ($line = $csvimport->next()) {
+
+        $newgroup = new stdClass();//to make Martin happy
+        foreach ($optionaldefaults as $key => $value) {
+            $newgroup->$key = current_language(); //defaults to current language
+        }
+        foreach ($line as $key => $value) {
+            $record[$header[$key]] = trim($value);
+        }
+        if (trim(implode($line)) !== '') {
+            // add a new group to the database
+
+            // add fields to object $user
+            foreach ($record as $name => $value) {
+                // check for required values
+                if (isset($required[$name]) and !$value) {
+                    throw new \moodle_exception('missingfield', 'error', $PAGE->url, $name);
+                } else if ($name == "groupname") {
+                    $newgroup->name = $value;
+                } else {
+                // normal entry
+                    $newgroup->{$name} = $value;
+                }
+            }
+
+            if (isset($newgroup->idnumber) && strlen($newgroup->idnumber)) {
+                //if idnumber is set, we use that.
+                //unset invalid courseid
+                if (!$mycourse = $DB->get_record('course', array('idnumber'=>$newgroup->idnumber))) {
+                    echo $OUTPUT->notification(get_string('unknowncourseidnumber', 'error', $newgroup->idnumber));
+                    unset($newgroup->courseid);//unset so 0 doesn't get written to database
+                } else {
+                    $newgroup->courseid = $mycourse->id;
+                }
+
+            } else if (isset($newgroup->coursename) && strlen($newgroup->coursename)) {
+                //else use course short name to look up
+                //unset invalid coursename (if no id)
+                if (!$mycourse = $DB->get_record('course', array('shortname' => $newgroup->coursename))) {
+                    echo $OUTPUT->notification(get_string('unknowncourse', 'error', $newgroup->coursename));
+                    unset($newgroup->courseid);//unset so 0 doesn't get written to database
+                } else {
+                    $newgroup->courseid = $mycourse->id;
+                }
+
+            } else {
+                //else use use current id
+                $newgroup->courseid = $id;
+            }
+            unset($newgroup->idnumber);
+            unset($newgroup->coursename);
+
+            //if courseid is set
+            if (isset($newgroup->courseid)) {
+                $linenum++;
+                $groupname = $newgroup->name;
+                $newgrpcoursecontext = context_course::instance($newgroup->courseid);
+
+                ///Users cannot upload groups in courses they cannot update.
+                if (!has_capability('moodle/course:managegroups', $newgrpcoursecontext) or (!is_enrolled($newgrpcoursecontext) and !has_capability('moodle/course:view', $newgrpcoursecontext))) {
+                    echo $OUTPUT->notification(get_string('nopermissionforcreation', 'group', $groupname));
+
+                } else {
+                    if (isset($newgroup->groupidnumber)) {
+                        // The CSV field for the group idnumber is groupidnumber rather than
+                        // idnumber as that field is already in use for the course idnumber.
+                        $newgroup->groupidnumber = trim($newgroup->groupidnumber);
+                        if (has_capability('moodle/course:changeidnumber', $newgrpcoursecontext)) {
+                            $newgroup->idnumber = $newgroup->groupidnumber;
+                            if ($existing = groups_get_group_by_idnumber($newgroup->courseid, $newgroup->idnumber)) {
+                                // idnumbers must be unique to a course but we shouldn't ignore group creation for duplicates
+                                $existing->name = s($existing->name);
+                                $existing->idnumber = s($existing->idnumber);
+                                $existing->problemgroup = $groupname;
+                                echo $OUTPUT->notification(get_string('groupexistforcoursewithidnumber', 'error', $existing));
+                                unset($newgroup->idnumber);
+                            }
+                        }
+                        // Always drop the groupidnumber key. It's not a valid database field
+                        unset($newgroup->groupidnumber);
+                    }
+                    if ($groupid = groups_get_group_by_name($newgroup->courseid, $groupname)) {
+                        echo $OUTPUT->notification("$groupname :".get_string('groupexistforcourse', 'error', $groupname));
+                    } else if ($groupid = groups_create_group($newgroup)) {
+                        echo $OUTPUT->notification(get_string('groupaddedsuccesfully', 'group', $groupname), 'notifysuccess');
+                    } else {
+                        echo $OUTPUT->notification(get_string('groupnotaddederror', 'error', $groupname));
+                        continue;
+                    }
+
+                    // Add group to grouping
+                    if (isset($newgroup->groupingname) && strlen($newgroup->groupingname)) {
+                        $groupingname = $newgroup->groupingname;
+                        if (! $groupingid = groups_get_grouping_by_name($newgroup->courseid, $groupingname)) {
+                            $data = new stdClass();
+                            $data->courseid = $newgroup->courseid;
+                            $data->name = $groupingname;
+                            // Add customfield if exists.
+                            foreach ($header as $fieldname) {
+                                if (isset($customfieldnames[$fieldname]) && isset($newgroup->$fieldname)) {
+                                    $data->{$groupingcustomfields[$groupingcustomfieldname]} = $newgroup->$fieldname;
+                                }
+                            }
+                            if ($groupingid = groups_create_grouping($data)) {
+                                echo $OUTPUT->notification(get_string('groupingaddedsuccesfully', 'group', $groupingname), 'notifysuccess');
+                            } else {
+                                echo $OUTPUT->notification(get_string('groupingnotaddederror', 'error', $groupingname));
+                                continue;
+                            }
+                        }
+
+                        // if we have reached here we definitely have a groupingid
+                        $a = array('groupname' => $groupname, 'groupingname' => $groupingname);
+                        try {
+                            groups_assign_grouping($groupingid, $groupid);
+                            echo $OUTPUT->notification(get_string('groupaddedtogroupingsuccesfully', 'group', $a), 'notifysuccess');
+                        } catch (Exception $e) {
+                            echo $OUTPUT->notification(get_string('groupnotaddedtogroupingerror', 'error', $a));
+                        }
+
+                    }
+                }
+            }
+            unset ($newgroup);
+        }
+    }
+
+    $csvimport->close();
+    echo $OUTPUT->single_button($returnurl, get_string('continue'), 'get');
+    echo $OUTPUT->footer();
+    die;
+}
+
+/// Print the form
+echo $OUTPUT->header();
+echo $OUTPUT->heading_with_help($strimportgroups, 'importgroups', 'core_group');
+$importform->display();
+echo $OUTPUT->footer();

group/import_form.php

@@ -0,0 +1,79 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * A form for group import.
+ *
+ * @package    core_group
+ * @copyright  2010 Toyomoyo (http://moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+if (!defined('MOODLE_INTERNAL')) {
+    die('Direct access to this script is forbidden.');    ///  It must be included from a Moodle page
+}
+
+require_once($CFG->libdir.'/formslib.php');
+require_once($CFG->libdir . '/csvlib.class.php');
+
+/**
+ * Groups import form class
+ *
+ * @package    core_group
+ * @copyright  2010 Toyomoyo (http://moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class groups_import_form extends moodleform {
+
+    /**
+     * Form definition
+     */
+    function definition() {
+        $mform =& $this->_form;
+        $data  = $this->_customdata;
+
+        //fill in the data depending on page params
+        //later using set_data
+        $mform->addElement('header', 'general', get_string('general'));
+
+        $filepickeroptions = array();
+        $filepickeroptions['filetypes'] = '*';
+        $filepickeroptions['maxbytes'] = get_max_upload_file_size();
+        $mform->addElement('filepicker', 'userfile', get_string('import'), null, $filepickeroptions);
+        $mform->addRule('userfile', null, 'required');
+
+        $mform->addElement('hidden', 'id');
+        $mform->setType('id', PARAM_INT);
+
+        $choices = csv_import_reader::get_delimiter_list();
+        $mform->addElement('select', 'delimiter_name', get_string('csvdelimiter', 'group'), $choices);
+        if (array_key_exists('cfg', $choices)) {
+            $mform->setDefault('delimiter_name', 'cfg');
+        } else if (get_string('listsep', 'langconfig') == ';') {
+            $mform->setDefault('delimiter_name', 'semicolon');
+        } else {
+            $mform->setDefault('delimiter_name', 'comma');
+        }
+
+        $choices = core_text::get_encodings();
+        $mform->addElement('select', 'encoding', get_string('encoding', 'group'), $choices);
+        $mform->setDefault('encoding', 'UTF-8');
+        $this->add_action_buttons(true, get_string('importgroups', 'core_group'));
+
+        $this->set_data($data);
+    }
+}
+

group/index.php

@@ -0,0 +1,266 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * The main group management user interface.
+ *
+ * @copyright 2006 The Open University, N.D.Freear AT open.ac.uk, J.White AT open.ac.uk
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+require_once('../config.php');
+require_once('lib.php');
+
+$courseid = required_param('id', PARAM_INT);
+$groupid  = optional_param('group', false, PARAM_INT);
+$userid   = optional_param('user', false, PARAM_INT);
+$action = optional_param('action', false, PARAM_TEXT);
+
+// Support either single group= parameter, or array groups[].
+if ($groupid) {
+    $groupids = array($groupid);
+} else {
+    $groupids = optional_param_array('groups', array(), PARAM_INT);
+}
+$singlegroup = (count($groupids) == 1);
+
+$returnurl = $CFG->wwwroot.'/group/index.php?id='.$courseid;
+
+// Get the course information so we can print the header and
+// check the course id is valid.
+$course = $DB->get_record('course', array('id' => $courseid), '*', MUST_EXIST);
+
+$url = new moodle_url('/group/index.php', array('id' => $courseid));
+navigation_node::override_active_url($url);
+if ($userid) {
+    $url->param('user', $userid);
+}
+if ($groupid) {
+    $url->param('group', $groupid);
+}
+$PAGE->set_url($url);
+
+// Make sure that the user has permissions to manage groups.
+require_login($course);
+
+$context = context_course::instance($course->id);
+require_capability('moodle/course:managegroups', $context);
+
+$PAGE->requires->js('/group/clientlib.js', true);
+$PAGE->requires->js('/group/module.js', true);
+
+// Check for multiple/no group errors.
+if (!$singlegroup) {
+    switch($action) {
+        case 'ajax_getmembersingroup':
+        case 'showgroupsettingsform':
+        case 'showaddmembersform':
+        case 'updatemembers':
+            throw new \moodle_exception('errorselectone', 'group', $returnurl);
+    }
+}
+
+switch ($action) {
+    case false: // OK, display form.
+        break;
+
+    case 'ajax_getmembersingroup':
+        $roles = array();
+
+        $userfieldsapi = \core_user\fields::for_identity($context)->with_userpic();
+        [
+            'selects' => $userfieldsselects,
+            'joins' => $userfieldsjoin,
+            'params' => $userfieldsparams
+        ] = (array)$userfieldsapi->get_sql('u', true, '', '', false);
+        $extrafields = $userfieldsapi->get_required_fields([\core_user\fields::PURPOSE_IDENTITY]);
+        if ($groupmemberroles = groups_get_members_by_role($groupids[0], $courseid,
+                'u.id, ' . $userfieldsselects, null, '', $userfieldsparams, $userfieldsjoin)) {
+
+            $viewfullnames = has_capability('moodle/site:viewfullnames', $context);
+
+            foreach ($groupmemberroles as $roleid => $roledata) {
+                $shortroledata = new stdClass();
+                $shortroledata->name = html_entity_decode($roledata->name, ENT_QUOTES, 'UTF-8');
+                $shortroledata->users = array();
+                foreach ($roledata->users as $member) {
+                    $shortmember = new stdClass();
+                    $shortmember->id = $member->id;
+                    $shortmember->name = fullname($member, $viewfullnames);
+                    if ($extrafields) {
+                        $extrafieldsdisplay = [];
+                        foreach ($extrafields as $field) {
+                            // No escaping here, handled client side in response to AJAX request.
+                            $extrafieldsdisplay[] = $member->{$field};
+                        }
+                        $shortmember->name .= ' (' . implode(', ', $extrafieldsdisplay) . ')';
+                    }
+
+                    $shortroledata->users[] = $shortmember;
+                }
+                $roles[] = $shortroledata;
+            }
+        }
+        echo json_encode($roles);
+        die;  // Client side JavaScript takes it from here.
+
+    case 'deletegroup':
+        if (count($groupids) == 0) {
+            throw new \moodle_exception('errorselectsome', 'group', $returnurl);
+        }
+        $groupidlist = implode(',', $groupids);
+        redirect(new moodle_url('/group/delete.php', array('courseid' => $courseid, 'groups' => $groupidlist)));
+        break;
+
+    case 'showcreateorphangroupform':
+        redirect(new moodle_url('/group/group.php', array('courseid' => $courseid)));
+        break;
+
+    case 'showautocreategroupsform':
+        redirect(new moodle_url('/group/autogroup.php', array('courseid' => $courseid)));
+        break;
+
+    case 'showimportgroups':
+        redirect(new moodle_url('/group/import.php', array('id' => $courseid)));
+        break;
+
+    case 'showgroupsettingsform':
+        redirect(new moodle_url('/group/group.php', array('courseid' => $courseid, 'id' => $groupids[0])));
+        break;
+
+    case 'updategroups': // Currently reloading.
+        break;
+
+    case 'removemembers':
+        break;
+
+    case 'showaddmembersform':
+        redirect(new moodle_url('/group/members.php', array('group' => $groupids[0])));
+        break;
+
+    case 'updatemembers': // Currently reloading.
+        break;
+
+    case 'enablemessaging':
+        set_groups_messaging($groupids, true);
+        redirect($returnurl, get_string('messagingenabled', 'group', count($groupids)), null,
+            \core\output\notification::NOTIFY_SUCCESS);
+        break;
+
+    case 'disablemessaging':
+        set_groups_messaging($groupids, false);
+        redirect($returnurl, get_string('messagingdisabled', 'group', count($groupids)), null,
+            \core\output\notification::NOTIFY_SUCCESS);
+        break;
+
+    default: // ERROR.
+        throw new \moodle_exception('unknowaction', '', $returnurl);
+        break;
+}
+
+// Print the page and form.
+$strgroups = get_string('groups');
+$strparticipants = get_string('participants');
+
+// Print header.
+$PAGE->set_title($strgroups);
+$PAGE->set_heading($course->fullname);
+$PAGE->set_pagelayout('standard');
+echo $OUTPUT->header();
+
+echo $OUTPUT->render_participants_tertiary_nav($course);
+
+$groups = groups_get_all_groups($courseid);
+$selectedname = null;
+$preventgroupremoval = array();
+
+// Get list of groups to render.
+$groupoptions = array();
+if ($groups) {
+    foreach ($groups as $group) {
+        $selected = false;
+        $usercount = $DB->count_records('groups_members', array('groupid' => $group->id));
+        $groupname = format_string($group->name, true, ['context' => $context, 'escape' => false]) . ' (' . $usercount . ')';
+        if (in_array($group->id, $groupids)) {
+            $selected = true;
+            if ($singlegroup) {
+                // Only keep selected name if there is one group selected.
+                $selectedname = $groupname;
+            }
+        }
+        if (!empty($group->idnumber) && !has_capability('moodle/course:changeidnumber', $context)) {
+            $preventgroupremoval[$group->id] = true;
+        }
+
+        $groupoptions[] = (object) [
+            'value' => $group->id,
+            'selected' => $selected,
+            'text' => s($groupname)
+        ];
+    }
+}
+
+// Get list of group members to render if there is a single selected group.
+$members = array();
+if ($singlegroup) {
+    $userfieldsapi = \core_user\fields::for_identity($context)->with_userpic();
+    [
+        'selects' => $userfieldsselects,
+        'joins' => $userfieldsjoin,
+        'params' => $userfieldsparams
+    ] = (array)$userfieldsapi->get_sql('u', true, '', '', false);
+    $extrafields = $userfieldsapi->get_required_fields([\core_user\fields::PURPOSE_IDENTITY]);
+    if ($groupmemberroles = groups_get_members_by_role(reset($groupids), $courseid,
+            'u.id, ' . $userfieldsselects, null, '', $userfieldsparams, $userfieldsjoin)) {
+
+        $viewfullnames = has_capability('moodle/site:viewfullnames', $context);
+
+        foreach ($groupmemberroles as $roleid => $roledata) {
+            $users = array();
+            foreach ($roledata->users as $member) {
+                $shortmember = new stdClass();
+                $shortmember->value = $member->id;
+                $shortmember->text = fullname($member, $viewfullnames);
+                if ($extrafields) {
+                    $extrafieldsdisplay = [];
+                    foreach ($extrafields as $field) {
+                        $extrafieldsdisplay[] = s($member->{$field});
+                    }
+                    $shortmember->text .= ' (' . implode(', ', $extrafieldsdisplay) . ')';
+                }
+
+                $users[] = $shortmember;
+            }
+
+            $members[] = (object)[
+                'role' => html_entity_decode($roledata->name, ENT_QUOTES, 'UTF-8'),
+                'rolemembers' => $users
+            ];
+        }
+    }
+}
+
+$disableaddedit = !$singlegroup;
+$disabledelete = !empty($groupids);
+$caneditmessaging = \core_message\api::can_create_group_conversation($USER->id, $context);
+
+$renderable = new \core_group\output\index_page($courseid, $groupoptions, $selectedname, $members, $disableaddedit, $disabledelete,
+        $preventgroupremoval, $caneditmessaging);
+$output = $PAGE->get_renderer('core_group');
+echo $output->render($renderable);
+
+echo $OUTPUT->footer();

group/members.php

@@ -0,0 +1,165 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * Add/remove members from group.
+ *
+ * @copyright 2006 The Open University and others, N.D.Freear AT open.ac.uk, J.White AT open.ac.uk and others
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   core_group
+ */
+require_once(__DIR__ . '/../config.php');
+require_once(__DIR__ . '/lib.php');
+require_once($CFG->dirroot . '/user/selector/lib.php');
+require_once($CFG->dirroot . '/course/lib.php');
+require_once($CFG->libdir . '/filelib.php');
+
+$groupid = required_param('group', PARAM_INT);
+$cancel  = optional_param('cancel', false, PARAM_BOOL);
+
+$group = $DB->get_record('groups', array('id'=>$groupid), '*', MUST_EXIST);
+$course = $DB->get_record('course', array('id'=>$group->courseid), '*', MUST_EXIST);
+
+$PAGE->set_url('/group/members.php', array('group'=>$groupid));
+$PAGE->set_pagelayout('admin');
+
+require_login($course);
+$context = context_course::instance($course->id);
+require_capability('moodle/course:managegroups', $context);
+
+$returnurl = $CFG->wwwroot.'/group/index.php?id='.$course->id.'&group='.$group->id;
+
+if ($cancel) {
+    redirect($returnurl);
+}
+
+$groupmembersselector = new group_members_selector('removeselect', array('groupid' => $groupid, 'courseid' => $course->id));
+$potentialmembersselector = new group_non_members_selector('addselect', array('groupid' => $groupid, 'courseid' => $course->id));
+
+if (optional_param('add', false, PARAM_BOOL) && confirm_sesskey()) {
+    $userstoadd = $potentialmembersselector->get_selected_users();
+    if (!empty($userstoadd)) {
+        foreach ($userstoadd as $user) {
+            if (!groups_add_member($groupid, $user->id)) {
+                throw new \moodle_exception('erroraddremoveuser', 'group', $returnurl);
+            }
+            $groupmembersselector->invalidate_selected_users();
+            $potentialmembersselector->invalidate_selected_users();
+        }
+    }
+}
+
+if (optional_param('remove', false, PARAM_BOOL) && confirm_sesskey()) {
+    $userstoremove = $groupmembersselector->get_selected_users();
+    if (!empty($userstoremove)) {
+        foreach ($userstoremove as $user) {
+            if (!groups_remove_member_allowed($groupid, $user->id)) {
+                throw new \moodle_exception('errorremovenotpermitted', 'group', $returnurl,
+                        $user->fullname);
+            }
+            if (!groups_remove_member($groupid, $user->id)) {
+                throw new \moodle_exception('erroraddremoveuser', 'group', $returnurl);
+            }
+            $groupmembersselector->invalidate_selected_users();
+            $potentialmembersselector->invalidate_selected_users();
+        }
+    }
+}
+
+// Print the page and form
+$strgroups = get_string('groups');
+$strparticipants = get_string('participants');
+$stradduserstogroup = get_string('adduserstogroup', 'group');
+$strusergroupmembership = get_string('usergroupmembership', 'group');
+
+$groupname = format_string($group->name);
+
+$PAGE->requires->js('/group/clientlib.js');
+$PAGE->navbar->add($strparticipants, new moodle_url('/user/index.php', array('id'=>$course->id)));
+$PAGE->navbar->add($strgroups, new moodle_url('/group/index.php', array('id'=>$course->id)));
+$PAGE->navbar->add($stradduserstogroup);
+
+/// Print header
+$PAGE->set_title("$course->shortname: $strgroups");
+$PAGE->set_heading($course->fullname);
+echo $OUTPUT->header();
+echo $OUTPUT->heading(get_string('adduserstogroup', 'group').": $groupname", 3);
+
+// Store the rows we want to display in the group info.
+$groupinforow = array();
+
+// Check if there is a description to display.
+if (!empty($group->description)) {
+    $grouprenderer = $PAGE->get_renderer('core_group');
+    $groupdetailpage = new \core_group\output\group_details($groupid);
+    echo $grouprenderer->group_details($groupdetailpage);
+}
+
+/// Print the editing form
+?>
+
+<div id="addmembersform">
+    <form id="assignform" method="post" action="<?php echo $CFG->wwwroot; ?>/group/members.php?group=<?php echo $groupid; ?>">
+    <div>
+    <input type="hidden" name="sesskey" value="<?php p(sesskey()); ?>" />
+
+    <table class="generaltable generalbox groupmanagementtable boxaligncenter" summary="">
+    <tr>
+      <td id='existingcell'>
+          <p>
+            <label for="removeselect"><?php print_string('groupmembers', 'group'); ?></label>
+          </p>
+          <?php $groupmembersselector->display(); ?>
+          </td>
+      <td id='buttonscell'>
+        <p class="arrow_button">
+            <input class="btn btn-secondary" name="add" id="add"
+                   type="submit" value="<?php echo $OUTPUT->larrow().'&nbsp;'.get_string('add'); ?>"
+                   title="<?php print_string('add'); ?>" /><br />
+            <input class="btn btn-secondary" name="remove" id="remove"
+                   type="submit" value="<?php echo get_string('remove').'&nbsp;'.$OUTPUT->rarrow(); ?>"
+                   title="<?php print_string('remove'); ?>" />
+        </p>
+      </td>
+      <td id='potentialcell'>
+          <p>
+            <label for="addselect"><?php print_string('potentialmembs', 'group'); ?></label>
+          </p>
+          <?php $potentialmembersselector->display(); ?>
+      </td>
+      <td>
+        <p><?php echo($strusergroupmembership) ?></p>
+        <div id="group-usersummary"></div>
+      </td>
+    </tr>
+    <tr><td colspan="3" id='backcell'>
+        <input class="btn btn-secondary" type="submit" name="cancel"
+               value="<?php print_string('backtogroups', 'group'); ?>" />
+    </td></tr>
+    </table>
+    </div>
+    </form>
+</div>
+
+<?php
+    //outputs the JS array used to display the other groups users are in
+    $potentialmembersselector->print_user_summaries($course->id);
+
+    //this must be after calling display() on the selectors so their setup JS executes first
+    $PAGE->requires->js_init_call('init_add_remove_members_page', null, false, $potentialmembersselector->get_js_module());
+
+    echo $OUTPUT->footer();

group/module.js

@@ -0,0 +1,42 @@
+/*
+ * To change this template, choose Tools | Templates
+ * and open the template in the editor.
+ */
+M.core_group = {
+    hoveroverlay : null
+};
+
+M.core_group.init_index = function(Y, wwwroot, courseid) {
+    M.core_group.groupsCombo = new UpdatableGroupsCombo(wwwroot, courseid);
+    M.core_group.membersCombo = new UpdatableMembersCombo(wwwroot, courseid);
+};
+
+M.core_group.groupslist = function(Y, preventgroupremoval) {
+    var actions = {
+        init : function() {
+            // We need to add check_deletable both on change for the groups, and then call it the first time the page loads
+            Y.one('#groups').on('change', this.check_deletable, this);
+            this.check_deletable();
+        },
+        check_deletable : function() {
+            // Ensure that if the 'preventremoval' attribute is set, the delete button is greyed out
+            var candelete = true;
+            var optionselected = false;
+            Y.one('#groups').get('options').each(function(option) {
+                if (option.get('selected')) {
+                    optionselected = true;
+                    if (option.getAttribute('value') in preventgroupremoval) {
+                        candelete = false;
+                    }
+                }
+            }, this);
+            var deletebutton = Y.one('#deletegroup');
+            if (candelete && optionselected) {
+                deletebutton.removeAttribute('disabled');
+            } else {
+                deletebutton.setAttribute('disabled', 'disabled');
+            }
+        }
+    }
+    actions.init();
+};

group/overview.php

@@ -0,0 +1,381 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+
+/**
+ * Print an overview of groupings & group membership
+ *
+ * @copyright  Matt Clarkson mattc@catalyst.net.nz
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package    core_group
+ */
+
+require_once('../config.php');
+require_once($CFG->libdir . '/filelib.php');
+
+define('OVERVIEW_NO_GROUP', -1); // The fake group for users not in a group.
+define('OVERVIEW_GROUPING_GROUP_NO_GROUPING', -1); // The fake grouping for groups that have no grouping.
+define('OVERVIEW_GROUPING_NO_GROUP', -2); // The fake grouping for users with no group.
+
+$courseid   = required_param('id', PARAM_INT);
+$groupid    = optional_param('group', 0, PARAM_INT);
+$groupingid = optional_param('grouping', 0, PARAM_INT);
+$dataformat = optional_param('dataformat', '', PARAM_ALPHA);
+
+$returnurl = $CFG->wwwroot.'/group/index.php?id='.$courseid;
+$rooturl   = $CFG->wwwroot.'/group/overview.php?id='.$courseid;
+
+if (!$course = $DB->get_record('course', array('id'=>$courseid))) {
+    throw new \moodle_exception('invalidcourse');
+}
+
+$url = new moodle_url('/group/overview.php', array('id'=>$courseid));
+if ($groupid !== 0) {
+    $url->param('group', $groupid);
+}
+if ($groupingid !== 0) {
+    $url->param('grouping', $groupingid);
+}
+$PAGE->set_url($url);
+
+// Make sure that the user has permissions to manage groups.
+require_login($course);
+
+$context = context_course::instance($courseid);
+require_capability('moodle/course:managegroups', $context);
+
+$strgroups           = get_string('groups');
+$strparticipants     = get_string('participants');
+$stroverview         = get_string('overview', 'group');
+$strgrouping         = get_string('grouping', 'group');
+$strgroup            = get_string('group', 'group');
+$strnotingrouping    = get_string('notingrouping', 'group');
+$strfiltergroups     = get_string('filtergroups', 'group');
+$strnogroups         = get_string('nogroups', 'group');
+$strdescription      = get_string('description');
+$strnotingroup       = get_string('notingrouplist', 'group');
+$strnogroup          = get_string('nogroup', 'group');
+$strnogrouping       = get_string('nogrouping', 'group');
+
+// This can show all users and all groups in a course.
+// This is lots of data so allow this script more resources.
+raise_memory_limit(MEMORY_EXTRA);
+
+// Get all groupings and sort them by formatted name.
+$groupings = $DB->get_records('groupings', array('courseid'=>$courseid), 'name');
+foreach ($groupings as $gid => $grouping) {
+    $groupings[$gid]->formattedname = format_string($grouping->name, true, array('context' => $context));
+}
+core_collator::asort_objects_by_property($groupings, 'formattedname');
+$members = array();
+foreach ($groupings as $grouping) {
+    $members[$grouping->id] = array();
+}
+// Groups not in a grouping.
+$members[OVERVIEW_GROUPING_GROUP_NO_GROUPING] = array();
+
+// Get all groups and sort them by formatted name.
+$groups = $DB->get_records('groups', array('courseid'=>$courseid), 'name');
+foreach ($groups as $id => $group) {
+    $groups[$id]->formattedname = format_string($group->name, true, ['context' => $context]);
+}
+core_collator::asort_objects_by_property($groups, 'formattedname');
+
+$params = array('courseid'=>$courseid);
+if ($groupid) {
+    $groupwhere = "AND g.id = :groupid";
+    $params['groupid']   = $groupid;
+} else {
+    $groupwhere = "";
+}
+
+if ($groupingid) {
+    if ($groupingid < 0) { // No grouping filter.
+        $groupingwhere = "AND gg.groupingid IS NULL";
+    } else {
+        $groupingwhere = "AND gg.groupingid = :groupingid";
+        $params['groupingid'] = $groupingid;
+    }
+} else {
+    $groupingwhere = "";
+}
+
+list($sort, $sortparams) = users_order_by_sql('u');
+
+$userfieldsapi = \core_user\fields::for_identity($context)->with_userpic();
+[
+    'selects' => $userfieldsselects,
+    'joins' => $userfieldsjoin,
+    'params' => $userfieldsparams
+] = (array)$userfieldsapi->get_sql('u', true);
+$extrafields = $userfieldsapi->get_required_fields([\core_user\fields::PURPOSE_IDENTITY]);
+$allnames = 'u.id ' . $userfieldsselects;
+
+$sql = "SELECT g.id AS groupid, gg.groupingid, u.id AS userid, $allnames, u.idnumber, u.username
+          FROM {groups} g
+               LEFT JOIN {groupings_groups} gg ON g.id = gg.groupid
+               LEFT JOIN {groups_members} gm ON g.id = gm.groupid
+               LEFT JOIN {user} u ON gm.userid = u.id
+               $userfieldsjoin
+         WHERE g.courseid = :courseid $groupwhere $groupingwhere
+      ORDER BY g.name, $sort";
+
+$rs = $DB->get_recordset_sql($sql, array_merge($params, $sortparams, $userfieldsparams));
+foreach ($rs as $row) {
+    $user = username_load_fields_from_object((object) [], $row, null,
+        array_merge(['id' => 'userid', 'username', 'idnumber'], $extrafields));
+
+    if (!$row->groupingid) {
+        $row->groupingid = OVERVIEW_GROUPING_GROUP_NO_GROUPING;
+    }
+    if (!array_key_exists($row->groupid, $members[$row->groupingid])) {
+        $members[$row->groupingid][$row->groupid] = array();
+    }
+    if (!empty($user->id)) {
+        $members[$row->groupingid][$row->groupid][] = $user;
+    }
+}
+$rs->close();
+
+// Add 'no groupings' / 'no groups' selectors.
+$groupings[OVERVIEW_GROUPING_GROUP_NO_GROUPING] = (object)array(
+    'id' => OVERVIEW_GROUPING_GROUP_NO_GROUPING,
+    'formattedname' => $strnogrouping,
+);
+$groups[OVERVIEW_NO_GROUP] = (object)array(
+    'id' => OVERVIEW_NO_GROUP,
+    'courseid' => $courseid,
+    'idnumber' => '',
+    'name' => $strnogroup,
+    'formattedname' => $strnogroup,
+    'description' => '',
+    'descriptionformat' => FORMAT_HTML,
+    'enrolmentkey' => '',
+    'picture' => 0,
+    'timecreated' => 0,
+    'timemodified' => 0,
+);
+
+// Add users who are not in a group.
+if ($groupid <= 0 && $groupingid <= 0) {
+    list($esql, $params) = get_enrolled_sql($context, null, 0, true);
+    $sql = "SELECT u.id, $allnames, u.idnumber, u.username
+              FROM {user} u
+              JOIN ($esql) e ON e.id = u.id
+         LEFT JOIN (
+                  SELECT gm.userid
+                    FROM {groups_members} gm
+                    JOIN {groups} g ON g.id = gm.groupid
+                   WHERE g.courseid = :courseid
+                   ) grouped ON grouped.userid = u.id
+                  $userfieldsjoin
+             WHERE grouped.userid IS NULL
+             ORDER BY $sort";
+    $params['courseid'] = $courseid;
+
+    $nogroupusers = $DB->get_records_sql($sql, array_merge($params, $userfieldsparams));
+
+    if ($nogroupusers) {
+        $members[OVERVIEW_GROUPING_NO_GROUP][OVERVIEW_NO_GROUP] = $nogroupusers;
+    }
+}
+
+// Export groups if requested.
+if ($dataformat !== '') {
+    $columnnames = array(
+        'grouping' => $strgrouping,
+        'group' => $strgroup,
+        'firstname' => get_string('firstname'),
+        'lastname' => get_string('lastname'),
+    );
+    $extrafields = \core_user\fields::get_identity_fields($context, false);
+    foreach ($extrafields as $field) {
+        $columnnames[$field] = \core_user\fields::get_display_name($field);
+    }
+    $alldata = array();
+    // Generate file name.
+    $shortname = format_string($course->shortname, true, array('context' => $context))."_groups";
+    $i = 0;
+    foreach ($members as $gpgid => $groupdata) {
+        if ($groupingid and $groupingid != $gpgid) {
+            if ($groupingid > 0 || $gpgid > 0) {
+                // Still show 'not in group' when 'no grouping' selected.
+                continue; // Do not export.
+            }
+        }
+        if ($gpgid < 0) {
+            // Display 'not in group' for grouping id == OVERVIEW_GROUPING_NO_GROUP.
+            if ($gpgid == OVERVIEW_GROUPING_NO_GROUP) {
+                $groupingname = $strnotingroup;
+            } else {
+                $groupingname = $strnotingrouping;
+            }
+        } else {
+            $groupingname = $groupings[$gpgid]->formattedname;
+        }
+        if (empty($groupdata)) {
+            $alldata[$i] = array_fill_keys(array_keys($columnnames), '');
+            $alldata[$i]['grouping'] = $groupingname;
+            $i++;
+        }
+        foreach ($groupdata as $gpid => $users) {
+            if ($groupid and $groupid != $gpid) {
+                continue;
+            }
+            if (empty($users)) {
+                $alldata[$i] = array_fill_keys(array_keys($columnnames), '');
+                $alldata[$i]['grouping'] = $groupingname;
+                $alldata[$i]['group'] = $groups[$gpid]->formattedname;
+                $i++;
+            }
+            foreach ($users as $option => $user) {
+                $alldata[$i]['grouping'] = $groupingname;
+                $alldata[$i]['group'] = $groups[$gpid]->formattedname;
+                $alldata[$i]['firstname'] = $user->firstname;
+                $alldata[$i]['lastname'] = $user->lastname;
+                foreach ($extrafields as $field) {
+                    $alldata[$i][$field] = $user->$field;
+                }
+                $i++;
+            }
+        }
+    }
+
+    \core\dataformat::download_data(
+        $shortname,
+        $dataformat,
+        $columnnames,
+        $alldata,
+        function($record, $supportshtml) use ($extrafields) {
+            if ($supportshtml) {
+                foreach ($extrafields as $extrafield) {
+                    $record[$extrafield] = s($record[$extrafield]);
+                }
+            }
+            return $record;
+        });
+    die;
+}
+
+// Main page content.
+navigation_node::override_active_url(new moodle_url('/group/index.php', array('id'=>$courseid)));
+$PAGE->navbar->add(get_string('overview', 'group'));
+
+/// Print header
+$PAGE->set_title($strgroups);
+$PAGE->set_heading($course->fullname);
+$PAGE->set_pagelayout('standard');
+
+echo $OUTPUT->header();
+echo $OUTPUT->render_participants_tertiary_nav($course);
+
+echo $strfiltergroups;
+
+$options = array();
+$options[0] = get_string('all');
+foreach ($groupings as $grouping) {
+    $options[$grouping->id] = strip_tags($grouping->formattedname);
+}
+$popupurl = new moodle_url($rooturl.'&group='.$groupid);
+$select = new single_select($popupurl, 'grouping', $options, $groupingid, array());
+$select->label = $strgrouping;
+$select->formid = 'selectgrouping';
+echo $OUTPUT->render($select);
+
+$options = array();
+$options[0] = get_string('all');
+foreach ($groups as $group) {
+    $options[$group->id] = $group->formattedname;
+}
+$popupurl = new moodle_url($rooturl.'&grouping='.$groupingid);
+$select = new single_select($popupurl, 'group', $options, $groupid, array());
+$select->label = $strgroup;
+$select->formid = 'selectgroup';
+echo $OUTPUT->render($select);
+
+/// Print table
+$printed = false;
+foreach ($members as $gpgid=>$groupdata) {
+    if ($groupingid and $groupingid != $gpgid) {
+        if ($groupingid > 0 || $gpgid > 0) { // Still show 'not in group' when 'no grouping' selected.
+            continue; // Do not show.
+        }
+    }
+    $table = new html_table();
+    $table->head  = array(get_string('groupscount', 'group', count($groupdata)), get_string('groupmembers', 'group'), get_string('usercount', 'group'));
+    $table->size  = array('20%', '70%', '10%');
+    $table->align = array('left', 'left', 'center');
+    $table->width = '90%';
+    $table->data  = array();
+    foreach ($groupdata as $gpid=>$users) {
+        if ($groupid and $groupid != $gpid) {
+            continue;
+        }
+        $line = array();
+        $name = print_group_picture($groups[$gpid], $course->id, false, true, false) . $groups[$gpid]->formattedname;
+        $description = file_rewrite_pluginfile_urls($groups[$gpid]->description, 'pluginfile.php', $context->id, 'group', 'description', $gpid);
+        $options = new stdClass;
+        $options->noclean = true;
+        $options->overflowdiv = true;
+        $line[] = $name;
+        $viewfullnames = has_capability('moodle/site:viewfullnames', $context);
+        $fullnames = array();
+        foreach ($users as $user) {
+            $displayname = fullname($user, $viewfullnames);
+            if ($extrafields) {
+                $extrafieldsdisplay = [];
+                foreach ($extrafields as $field) {
+                    $extrafieldsdisplay[] = s($user->{$field});
+                }
+                $displayname .= ' (' . implode(', ', $extrafieldsdisplay) . ')';
+            }
+
+            $fullnames[] = html_writer::link(new moodle_url('/user/view.php', ['id' => $user->id, 'course' => $course->id]),
+                $displayname);
+        }
+        $line[] = implode(', ', $fullnames);
+        $line[] = count($users);
+        $table->data[] = $line;
+    }
+    if ($groupid and empty($table->data)) {
+        continue;
+    }
+    if ($gpgid < 0) {
+        // Display 'not in group' for grouping id == OVERVIEW_GROUPING_NO_GROUP.
+        if ($gpgid == OVERVIEW_GROUPING_NO_GROUP) {
+            echo $OUTPUT->heading($strnotingroup, 3);
+        } else {
+            echo $OUTPUT->heading($strnotingrouping, 3);
+        }
+    } else {
+        echo $OUTPUT->heading($groupings[$gpgid]->formattedname, 3);
+        $description = file_rewrite_pluginfile_urls($groupings[$gpgid]->description, 'pluginfile.php', $context->id, 'grouping', 'description', $gpgid);
+        $options = new stdClass;
+        $options->overflowdiv = true;
+        echo $OUTPUT->box(format_text($description, $groupings[$gpgid]->descriptionformat, $options), 'generalbox boxwidthnarrow boxaligncenter');
+    }
+    echo html_writer::table($table);
+    $printed = true;
+}
+
+// Add buttons for exporting groups/groupings.
+echo $OUTPUT->download_dataformat_selector(get_string('exportgroupsgroupings', 'group'), 'overview.php', 'dataformat', [
+    'id' => $courseid,
+    'group' => $groupid,
+    'grouping' => $groupingid,
+]);
+
+echo $OUTPUT->footer();

group/tabs.php

@@ -0,0 +1,38 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Prints navigation tabs
+ *
+ * @package    core_group
+ * @copyright  2010 Petr Skoda (http://moodle.com)
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+    $row = array();
+    $row[] = new tabobject('groups',
+                           new moodle_url('/group/index.php', array('id' => $courseid)),
+                           get_string('groups'));
+
+    $row[] = new tabobject('groupings',
+                           new moodle_url('/group/groupings.php', array('id' => $courseid)),
+                           get_string('groupings', 'group'));
+
+    $row[] = new tabobject('overview',
+                           new moodle_url('/group/overview.php', array('id' => $courseid)),
+                           get_string('overview', 'group'));
+    echo '<div class="groupdisplay">';
+    echo $OUTPUT->tabtree($row, $currenttab);
+    echo '</div>';

group/templates/comboboxsearch/group_selector.mustache

@@ -0,0 +1,44 @@
+{{!
+    This file is part of Moodle - http://moodle.org/
+
+    Moodle is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Moodle is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+}}
+{{!
+    @template core_group/comboboxsearch/group_selector
+
+    The group selector trigger element.
+
+    Context variables required for this template:
+    * label - The label text fot the group selector element.
+    * group - The value of the group selector element (id of the preselected group)
+    * selectedgroup - The text of the selected group option.
+
+    Example context (json):
+    {
+        "label": "Select separate groups",
+        "group": "21",
+        "selectedgroup": "Group 1"
+    }
+}}
+<span class="d-none" data-region="groupid" data-groupid="{{group}}"></span>
+<div class="align-items-center d-flex">
+    <div class="d-block pr-3 text-truncate">
+        <span class="d-block small" aria-hidden="true">
+            {{label}}
+        </span>
+        <span class="p-0 font-weight-bold">
+            {{selectedgroup}}
+        </span>
+    </div>
+</div>

group/templates/comboboxsearch/resultitem.mustache

@@ -0,0 +1,42 @@
+{{!
+    This file is part of Moodle - http://moodle.org/
+    Moodle is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+    Moodle is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+    You should have received a copy of the GNU General Public License
+    along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+}}
+{{!
+    @template core_group/comboboxsearch/resultitem
+
+    Template for the individual result item.
+
+    Context variables required for this template:
+    * id - Group system ID.
+    * name - Groups' name.
+    * groupimageurl - The link of the groups picture.
+
+    Example context (json):
+    {
+        "id": 2,
+        "name": "Foo bar",
+        "groupimageurl": "http://foo.bar/grade/report/grader/index.php?id=42&userid=2"
+    }
+}}
+{{<core/local/comboboxsearch/resultitem }}
+    {{$content}}
+        <div class="pr-2 pl-1 w-25">
+            <img class="rounded-circle mx-auto img-fluid" src="{{groupimageurl}}" alt=""/>
+        </div>
+        <div class="pr-3 w-75">
+            <span class="d-block w-100 p-0 text-truncate">
+                {{name}}
+            </span>
+        </div>
+    {{/content}}
+{{/core/local/comboboxsearch/resultitem}}

group/templates/comboboxsearch/resultset.mustache

@@ -0,0 +1,51 @@
+{{!
+    This file is part of Moodle - http://moodle.org/
+    Moodle is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+    Moodle is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+    You should have received a copy of the GNU General Public License
+    along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+}}
+{{!
+    @template core_group/comboboxsearch/resultset
+
+    Wrapping template for returned result items.
+
+    Context variables required for this template:
+    * groups - Our returned groups to render.
+    * instance - The instance ID of the combo box.
+    * searchterm - The entered text to find these results.
+    * hasgroups - Allow the handling where no users exist for the returned search term.
+
+    Example context (json):
+    {
+        "groups": [
+            {
+                "id": 2,
+                "name": "Foo bar",
+                "link": "http://foo.bar/grade/report/grader/index.php?id=42&userid=2"
+            },
+            {
+                "id": 3,
+                "name": "Bar Foo",
+                "link": "http://foo.bar/grade/report/grader/index.php?id=42&userid=3"
+            }
+        ],
+        "instance": 25,
+        "searchterm": "Foo",
+        "hasresults": true
+    }
+}}
+{{<core/local/comboboxsearch/resultset}}
+    {{$listid}}groups{{/listid}}
+    {{$results}}
+        {{#groups}}
+            {{>core_group/comboboxsearch/resultitem}}
+        {{/groups}}
+    {{/results}}
+{{/core/local/comboboxsearch/resultset}}

group/templates/comboboxsearch/searchbody.mustache

@@ -0,0 +1,55 @@
+{{!
+    This file is part of Moodle - http://moodle.org/
+    Moodle is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+    Moodle is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+    You should have received a copy of the GNU General Public License
+    along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+}}
+{{!
+    @template core_group/comboboxsearch/searchbody
+
+    Wrapping template for search input.
+
+    Context variables required for this template:
+    * courseid - The id of the course to search within.
+    * groupid - The id of the group to search within.
+    * currentvalue - The prefill value for the search input if provided
+
+    Example context (json):
+    {
+        "courseid": 2,
+        "groupid": 25,
+        "currentvalue": "bar"
+    }
+}}
+<div class="flex-column h-100 w-100">
+    <span class="d-none" data-region="courseid" data-courseid="{{courseid}}"></span>
+    <span class="d-none" data-region="groupid" data-groupid="{{groupid}}"></span>
+    <span class="d-none" data-region="instance" data-instance="{{instance}}"></span>
+
+    {{< core/search_input_auto }}
+        {{$label}}{{#str}}
+            searchgroups, core
+        {{/str}}{{/label}}
+        {{$placeholder}}{{#str}}
+            searchgroups, core
+        {{/str}}{{/placeholder}}
+        {{$value}}{{currentvalue}}{{/value}}
+        {{$additionalattributes}}
+            role="combobox"
+            aria-expanded="true"
+            aria-controls="groups-{{instance}}-result-listbox"
+            aria-autocomplete="list"
+            data-input-element="input-{{uniqid}}-{{instance}}"
+        {{/additionalattributes}}
+    {{/ core/search_input_auto }}
+    <input type="hidden" name="search" id="input-{{uniqid}}-{{instance}}"/>
+
+    <div data-region="searchplaceholder"></div>
+</div>

group/templates/group_details.mustache

@@ -0,0 +1,53 @@
+{{!
+    This file is part of Moodle - http://moodle.org/
+
+    Moodle is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Moodle is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+}}
+{{!
+    @template core_group/group_details
+
+    Template for the Groups page.
+
+    Classes required for JS:
+    * none
+
+    Data attributes required for JS:
+    * none
+
+    Context variables required for this template:
+    * name string Group Name
+    * pictureurl string Group image url
+    * description string Group description
+    * edit string edit link to edit the group
+
+    Example context (json):
+    {
+        "name": "Group Name",
+        "pictureurl": "https://raw.githubusercontent.com/moodle/moodle/master/pix/g/f1.png",
+        "description": "This is the description for Group Name",
+        "editurl": "http://www.moodle.org"
+    }
+}}
+{{#name}}
+<div class="groupinfobox container-fluid card p-3">
+    {{#pictureurl}}
+    <div class="group-image"><img class="grouppicture" src="{{{pictureurl}}}" alt="{{{name}}}" title="{{{name}}}"/></div>
+    {{/pictureurl}}
+    {{#editurl}}
+    <div class="group-edit"><a href="{{editurl}}">{{#pix}}t/edit, core, {{#str}}editgroupprofile{{/str}}{{/pix}}</a></div>
+    {{/editurl}}
+    <h3 class="">{{{name}}}</h3>
+    <div class="group-description">{{{description}}}</div>
+</div>
+{{/name}}

group/templates/index.mustache

@@ -0,0 +1,160 @@
+{{!
+    This file is part of Moodle - http://moodle.org/
+
+    Moodle is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Moodle is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+}}
+{{!
+    @template core_group/index
+
+    Template for the Groups page.
+
+    Classes required for JS:
+    * none
+
+    Data attributes required for JS:
+    * none
+
+    Context variables required for this template:
+    * courseid int The course ID.
+    * selectedgroup string The initially selected group.
+    * editgroupsettingsdisabled bool Whether to disable the "Edit group settings" button on load.
+    * deletegroupdisabled bool Whether to disable the "Delete selected group" button on load.
+    * addmembersdisabled bool Whether to disable the "Add/remove users" button on load.
+    * groups array The list of groups.
+    * members array The list of members, grouped based on roles.
+    * undeletablegroups string A JSON string containing an array of group IDs that a user cannot delete.
+    * messagingsettingsvisible bool Wether the messaging settings buttons should be visible.
+
+    Example context (json):
+    {
+        "courseid": "1",
+        "selectedgroup": "Group 1 (3)",
+        "editgroupsettingsdisabled": false,
+        "deletegroupdisabled": false,
+        "addmembersdisabled": false,
+        "messagingenabled": true,
+        "groups": [
+            {
+                "value": "1",
+                "text": "Group 1 (3)",
+                "selected": true
+            },
+            {
+                "value": "2",
+                "text": "Group 2 (2)"
+            }
+        ],
+        "members": [
+            {
+                "role": "Student",
+                "rolemembers": [
+                    {
+                        "value": "1",
+                        "text": "John Doe"
+                    },
+                    {
+                        "value": "2",
+                        "text": "Jane Doe"
+                    },
+                    {
+                        "value": "3",
+                        "text": "John Smith"
+                    }
+                ]
+            }
+        ],
+        "undeletablegroups": "[1: true, 3: true]"
+    }
+}}
+<form id="groupeditform" action="index.php" method="post">
+    <div class="container-fluid groupmanagementtable">
+        <div class="row rtl-compatible">
+            <div class="col-md-6 mb-1">
+                <input type="hidden" name="id" value="{{courseid}}">
+                <div class="mb-3">
+                    <label for="groups">
+                        <span id="groupslabel">{{#str}}groups{{/str}}</span>
+                        <span id="thegrouping">&nbsp;</span>
+                    </label>
+                    <select name="groups[]" multiple="multiple" id="groups" size="15" class="form-control input-block-level">
+                        {{#groups}}
+                            <option value="{{value}}" {{#selected}}selected="selected"{{/selected}} title="{{{text}}}">{{{text}}}</option>
+                        {{/groups}}
+                    </select>
+                </div>
+                <h3> {{#str}} withselected, group {{/str}} </h3>
+                <div class="mb-3">
+                    <button type="submit" name="action" id="updatemembers" value="updatemembers" class="btn btn-secondary">{{#str}}showmembersforgroup, group{{/str}}</button>
+                </div>
+                <div class="mb-3">
+                    <button type="submit" name="action" id="showeditgroupsettingsform" value="showgroupsettingsform" {{#editgroupsettingsdisabled}}disabled="disabled"{{/editgroupsettingsdisabled}} class="btn btn-secondary">{{#str}}editgroupsettings, group{{/str}}</button>
+                </div>
+                <div class="mb-3">
+                    <button type="submit" name="action" id="deletegroup" value="deletegroup" {{#deletegroupdisabled}}disabled="disabled"{{/deletegroupdisabled}} class="btn btn-secondary">{{#str}}deleteselectedgroup, group{{/str}}</button>
+                </div>
+                {{#messagingsettingsvisible}}
+                    <div class="mb-3">
+                        <button type="submit" name="action" id="disablemessaging" value="disablemessaging" class="btn btn-secondary" disabled="disabled">{{#str}}disablemessagingaction, group{{/str}}</button>
+                    </div>
+                    <div class="mb-3">
+                        <button type="submit" name="action" id="enablemessaging" value="enablemessaging" class="btn btn-secondary" disabled="disabled">{{#str}}enablemessagingaction, group{{/str}}</button>
+                    </div>
+                {{/messagingsettingsvisible}}
+                <h3> {{#str}} manageactions, group {{/str}} </h3>
+                <div class="mb-3">
+                    <button type="submit" name="action" id="showcreateorphangroupform" value="showcreateorphangroupform" class="btn btn-secondary">{{#str}}creategroup, group{{/str}}</button>
+                </div>
+                <div class="mb-3">
+                    <button type="submit" name="action" id="showautocreategroupsform" value="showautocreategroupsform" class="btn btn-secondary">{{#str}}autocreategroups, group{{/str}}</button>
+                </div>
+                <div class="mb-3">
+                    <button type="submit" name="action" id="showimportgroups" value="showimportgroups" class="btn btn-secondary">{{#str}}importgroups, group{{/str}}</button>
+                </div>
+            </div>
+            <div class="col-md-6 mb-1">
+                <div class="mb-3">
+                    <label for="members">
+                        <span id="memberslabel">{{#str}}membersofselectedgroup, group{{/str}}</span>
+                        <span id="thegroup">{{{selectedgroup}}}</span>
+                    </label>
+                    <select size="15" multiple="multiple" class="form-control input-block-level" id="members" name="user">
+                        {{#members}}
+                            <optgroup label="{{role}}">
+                                {{#rolemembers}}
+                                    <option value="{{value}}" title="{{text}}">{{{text}}}</option>
+                                {{/rolemembers}}
+                            </optgroup>
+                        {{/members}}
+                    </select>
+                </div>
+                <div class="mb-3">
+                    <button type="submit" value="showaddmembersform" class="btn btn-secondary" {{#addmembersdisabled}}disabled="disabled"{{/addmembersdisabled}} name="action" id="showaddmembersform">{{#str}}adduserstogroup, group{{/str}}</button>
+                </div>
+            </div>
+        </div>
+    </div>
+</form>
+{{#js}}
+    require(['jquery', 'core/yui'], function($) {
+        $("#groups").change(function() {
+            M.core_group.membersCombo.refreshMembers();
+        });
+        M.core_group.init_index(Y, "{{wwwroot}}", {{courseid}});
+        var undeletableGroups = JSON.parse('{{{undeletablegroups}}}');
+        M.core_group.groupslist(Y, undeletableGroups);
+    });
+{{/js}}
+{{#js}}
+    require(['core_group/index'], (module) => module.init());
+{{/js}}

group/tests/behat/auto_creation.feature

@@ -0,0 +1,193 @@
+@core @core_group
+Feature: Automatic creation of groups
+  In order to quickly create groups
+  As a teacher
+  I need to create groups automatically and allocate them in groupings if necessary
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | category |
+      | Course 1 | C1 | 0 |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+      | student1 | Student | 1 | student1@example.com |
+      | student2 | Student | 2 | student2@example.com |
+      | student3 | Student | 3 | student3@example.com |
+      | student4 | Student | 4 | student4@example.com |
+      | student5 | Student | 5 | student5@example.com |
+      | student6 | Student | 6 | student6@example.com |
+      | student7 | Student | 7 | student7@example.com |
+      | student8 | Student | 8 | student8@example.com |
+      | student9 | Student | 9 | student9@example.com |
+      | student10 | Student | 10 | student10@example.com |
+      | suspendedstudent11 | Suspended student | 11 | suspendedstudent11@example.com |
+    And the following "course enrolments" exist:
+      | user | course | role | status |
+      | teacher1 | C1 | editingteacher | 0 |
+      | student1 | C1 | student | 0 |
+      | student2 | C1 | student | 0 |
+      | student3 | C1 | student | 0 |
+      | student4 | C1 | student | 0 |
+      | student5 | C1 | student | 0 |
+      | student6 | C1 | student | 0 |
+      | student7 | C1 | student | 0 |
+      | student8 | C1 | student | 0 |
+      | student9 | C1 | student | 0 |
+      | student10 | C1 | student | 0 |
+      | suspendedstudent11 | C1 | student | 1 |
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    When I press "Auto-create groups"
+    And I expand all fieldsets
+
+  @javascript
+  Scenario: Split automatically the course users in groups and add the groups to a new grouping
+    Given I set the following fields to these values:
+      | Auto create based on | Number of groups |
+      | Group/member count | 2 |
+      | Grouping of auto-created groups | New grouping |
+      | Grouping name | Grouping name |
+    And I press "Preview"
+    Then I should see "Group members"
+    And I should see "User count"
+    And I should see "Group A"
+    And I should see "Group B"
+    And I press "Submit"
+    And the "groups" select box should contain "Group A (5)"
+    And the "groups" select box should contain "Group B (5)"
+    # Check that group messaging is not enabled for the auto-created groups.
+    And I set the field "groups" to "Group A"
+    And I press "Edit group settings"
+    And I should see "No" in the "Group messaging" "select"
+    And I press "Cancel"
+    And I set the field "groups" to "Group B"
+    And I press "Edit group settings"
+    And I should see "No" in the "Group messaging" "select"
+    And I press "Cancel"
+    # Check groupings.
+    And I set the field "Participants tertiary navigation" to "Groupings"
+    And I should see "Grouping name"
+    And I click on "Show groups in grouping" "link" in the "Grouping name" "table_row"
+    And the "removeselect" select box should contain "Group A"
+    And the "removeselect" select box should contain "Group B"
+
+  @javascript
+  Scenario: Split automatically the course users in groups based on group member count
+    Given I set the following fields to these values:
+      | Auto create based on | Members per group |
+      | Group/member count | 4 |
+      | Grouping of auto-created groups | New grouping |
+      | Grouping name | Grouping name |
+      | Allocate members | Alphabetically by last name, first name |
+    And I press "Preview"
+    Then the following should exist in the "generaltable" table:
+      | Groups (3)   | Group members                    | User count (10) |
+      | Group A      | Student 1 (student1@example.com) | 4               |
+      | Group B      | Student 5 (student5@example.com) | 4               |
+      | Group C      | Student 9 (student9@example.com) | 2               |
+    And I set the field "Prevent last small group" to "1"
+    And I press "Preview"
+    And I should see "Group A" in the ".generaltable" "css_element"
+    And I should see "Group B" in the ".generaltable" "css_element"
+    And I should see "5" in the "Group A" "table_row"
+    And I should see "5" in the "Group B" "table_row"
+
+  @javascript
+  Scenario: Split automatically the course users in groups that are not in groups
+    Given I press "Cancel"
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group 1 |
+    And I press "Save changes"
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group 2 |
+    And I press "Save changes"
+    When I add "Student 1" user to "Group 1" group members
+    And I add "Student 2" user to "Group 1" group members
+    And I add "Student 3" user to "Group 2" group members
+    And I add "Student 4" user to "Group 2" group members
+    And I press "Auto-create groups"
+    And I expand all fieldsets
+    And I set the field "Auto create based on" to "Number of groups"
+    And I set the field "Group/member count" to "2"
+    And I set the field "Grouping of auto-created groups" to "No grouping"
+    And I set the field "Ignore users in groups" to "1"
+    And I press "Submit"
+    And the "groups" select box should contain "Group A (3)"
+    And the "groups" select box should contain "Group B (3)"
+
+  @javascript
+  Scenario: Split users into groups based on existing groups or groupings
+    Given I set the following fields to these values:
+      | Naming scheme | Group @ |
+      | Auto create based on | Number of groups |
+      | Group/member count | 2 |
+      | Grouping of auto-created groups | No grouping |
+    And I press "Submit"
+    And I press "Auto-create groups"
+    And I set the following fields to these values:
+      | Naming scheme | Test @ |
+      | Auto create based on | Number of groups |
+      | Group/member count | 2 |
+      | groupid | Group A |
+      | Grouping of auto-created groups | New grouping |
+      | Grouping name | Sub Grouping |
+    And I press "Submit"
+    And the "groups" select box should contain "Test A (3)"
+    And the "groups" select box should contain "Test B (2)"
+    And I press "Auto-create groups"
+    And I set the following fields to these values:
+      | Naming scheme | Test # |
+      | Auto create based on | Number of groups |
+      | Group/member count | 2 |
+      | Select members from grouping | Sub Grouping |
+      | Grouping of auto-created groups | No grouping |
+    And I press "Submit"
+    And the "groups" select box should contain "Test 1 (3)"
+    And the "groups" select box should contain "Test 2 (2)"
+
+  Scenario: Exclude suspended users when auto-creating groups
+    Given I set the field "Include only active enrolments" to "1"
+    And I set the field "Auto create based on" to "Members per group"
+    When I set the field "Group/member count" to "11"
+    And I press "Preview"
+    Then I should not see "Suspended Student 11"
+
+  Scenario: Include suspended users when auto-creating groups
+    Given I set the field "Include only active enrolments" to "0"
+    And I set the field "Auto create based on" to "Members per group"
+    When I set the field "Group/member count" to "11"
+    And I press "Preview"
+    Then I should see "Suspended student 11 (suspendedstudent11@example.com)"
+
+  Scenario: Do not display 'Include only active enrolments' if user does not have the 'moodle/course:viewsuspendedusers' capability
+    Given I log out
+    And the following "role capability" exists:
+      | role                             | editingteacher |
+      | moodle/course:viewsuspendedusers | prevent        |
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    When I press "Auto-create groups"
+    Then I should not see "Include only active enrolments"
+    And I set the field "Group/member count" to "11"
+    And I press "Preview"
+    And I should not see "Suspended Student 11"
+
+  @javascript
+  Scenario: Auto-create groups with group messaging
+    Given I set the following fields to these values:
+      | Naming scheme | Group @ |
+      | Auto create based on | Number of groups |
+      | Group/member count | 2 |
+      | Grouping of auto-created groups | No grouping |
+      | Group messaging | Yes |
+    And I press "Submit"
+    And I set the field "groups" to "Group A"
+    When I press "Edit group settings"
+    Then I should see "Yes" in the "Group messaging" "select"
+    And I press "Cancel"
+    And I set the field "groups" to "Group B"
+    And I press "Edit group settings"
+    And I should see "Yes" in the "Group messaging" "select"

group/tests/behat/backup_restore_groups.feature

@@ -0,0 +1,50 @@
+@core @core_group
+Feature: Backup and restore a course containing groups
+  In order to transfer groups to another course
+  As a teacher
+  I want to backup and restore a course retaining the groups
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | format | enablecompletion | numsections |
+      | Course 1 | C1        | topics | 1                | 3           |
+    And the following "users" exist:
+      | username | firstname | lastname |
+      | teacher1 | Teacher   | Teacher  |
+    And the following "course enrolments" exist:
+      | user     | course | role           |
+      | teacher1 | C1     | editingteacher |
+    And the following "groups" exist:
+      | name                                      | course | idnumber | visibility | participation |
+      | Visible/Participation                     | C1     | VP       | 0          | 1             |
+      | Only visible to members/Participation     | C1     | MP       | 1          | 1             |
+      | Only see own membership                   | C1     | O        | 2          | 0             |
+      | Not visible                               | C1     | N        | 3          | 0             |
+      | Visible/Non-Participation                 | C1     | VN       | 0          | 0             |
+      | Only visible to members/Non-Participation | C1     | MN       | 1          | 0             |
+    And the following config values are set as admin:
+      | enableasyncbackup | 0 |
+    And I log in as "admin"
+    And I backup "Course 1" course using this options:
+      | Confirmation | Filename | test_backup.mbz |
+    And I restore "test_backup.mbz" backup into a new course using this options:
+      | Schema | Course name | Restored course |
+
+  @javascript
+  Scenario Outline: Check restored groups
+    Given I am on the "Restored course copy 1" "groups" page logged in as teacher1
+    When I set the field "Groups" to "<group>"
+    And I press "Edit group settings"
+    Then the following fields match these values:
+      | Group ID number              | <idnumber>      |
+      | Group membership visibility             | <visibility>    |
+      | Show group in dropdown menu for activities in group mode | <participation> |
+
+    Examples:
+      | group                                     | idnumber | visibility | participation |
+      | Visible/Participation                     | VP       | 0          | 1             |
+      | Only visible to members/Participation     | MP       | 1          | 1             |
+      | Only see own membership                   | O        | 2          | 0             |
+      | Not visible                               | N        | 3          | 0             |
+      | Visible/Non-Participation                 | VN       | 0          | 0             |
+      | Only visible to members/Non-Participation | MN       | 1          | 0             |

group/tests/behat/behat_groups.php

@@ -0,0 +1,86 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Behat groups-related steps definitions.
+ *
+ * @package    core_group
+ * @category   test
+ * @copyright  2013 David Monllaó
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+// NOTE: no MOODLE_INTERNAL test here, this file may be required by behat before including /config.php.
+
+require_once(__DIR__ . '/../../../lib/behat/behat_base.php');
+
+use Behat\Mink\Exception\ElementNotFoundException as ElementNotFoundException;
+
+/**
+ * Groups-related steps definitions.
+ *
+ * @package    core_group
+ * @category   test
+ * @copyright  2013 David Monllaó
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class behat_groups extends behat_base {
+
+    /**
+     * Add the specified user to the group. You should be in the groups page when running this step. The user should be specified like "Firstname Lastname (user@example.com)".
+     *
+     * @Given /^I add "(?P<user_fullname_string>(?:[^"]|\\")*)" user to "(?P<group_name_string>(?:[^"]|\\")*)" group members$/
+     * @throws ElementNotFoundException Thrown by behat_base::find
+     * @param string $username
+     * @param string $groupname
+     */
+    public function i_add_user_to_group_members($userfullname, $groupname) {
+        // Select the group in the select.
+        $this->execute('behat_forms::i_set_the_field_to', [get_string('groups', 'core'), $this->escape($groupname)]);
+
+        // Press "Add/remove users".
+        $this->execute('behat_general::i_click_on', [get_string('adduserstogroup', 'group'), "button"]);
+
+        // Select the user.
+        $this->execute('behat_forms::i_set_the_field_to', ["addselect", $this->escape($userfullname)]);
+
+        // Click add button.
+        $this->execute('behat_general::i_click_on', [get_string('add', 'core'), "button"]);
+
+        // Returning to the main groups page.
+        $this->execute('behat_general::i_click_on', [get_string('backtogroups', 'group'), "button"]);
+    }
+
+    /**
+     * A single or comma-separated list of groups expected within a grouping, on group overview page.
+     *
+     * @Given /^the group overview should include groups "(?P<groups_string>(?:[^"]|\\")*)" in grouping "(?P<grouping_string>(?:[^"]|\\")*)"$/
+     * @param string $groups one or comma seperated list of groups.
+     * @param string $grouping grouping in which all group should be present.
+     */
+    public function the_groups_overview_should_include_groups_in_grouping($groups, $grouping) {
+
+        $groups = array_map('trim', explode(',', $groups));
+
+        foreach ($groups as $groupname) {
+            // Find the table after the H3 containing the grouping name, then look for the group name in the first column.
+            $xpath = "//h3[normalize-space(.) = '{$grouping}']/following-sibling::div[contains(@class, 'table-responsive')]" .
+                "/table//tr//td[contains(concat(' ', normalize-space(@class), ' '), ' c0 ')][normalize-space(.) = '{$groupname}' ]";
+
+            $this->execute('behat_general::should_exist', array($xpath, 'xpath_element'));
+        }
+    }
+}

group/tests/behat/bulk_messaging.feature

@@ -0,0 +1,58 @@
+@core @core_group
+Feature: Bulk update group messaging status
+  In order to update group messaging settings in bulk
+  As a teacher
+  I need to be able to select the groups and update their messaging settings using the buttons provided.
+
+  Background:
+    Given the following "courses" exist:
+        | fullname | shortname | format |
+        | Course 1 | C1        | topics |
+    And the following "users" exist:
+        | username | firstname | lastname | email                |
+        | teacher1 | Teacher   | 1        | teacher1@example.com |
+    And the following "course enrolments" exist:
+        | user     | course | role           |
+        | teacher1 | C1     | editingteacher |
+    And the following "groups" exist:
+        | course | name         | idnumber |
+        | C1     | Group-A-Test | GA       |
+        | C1     | Group-B-Test | GB       |
+    And I am on the "Course 1" "groups" page logged in as "teacher1"
+
+  @javascript
+  Scenario: Bulk enable messaging in groups
+    Given I set the field "groups" to "Group-A-Test (0)"
+    And I press "Edit group settings"
+    And I set the field "id_enablemessaging" to "0"
+    And I press "Save changes"
+    And I wait until the page is ready
+    And the field "groups" matches value "Group-A-Test (0)"
+    And I press "Enable messaging"
+    And I wait until the page is ready
+    And I should see "Successfully enabled messaging in 1 group(s)"
+    And I set the field "groups" to "Group-A-Test (0)"
+    And I press "Edit group settings"
+    Then the field "id_enablemessaging" matches value "1"
+
+  @javascript
+  Scenario: Bulk disable messaging in groups
+    Given I set the field "groups" to "Group-A-Test (0)"
+    And I press "Edit group settings"
+    And I set the field "id_enablemessaging" to "1"
+    And I press "Save changes"
+    And I wait until the page is ready
+    And the field "groups" matches value "Group-A-Test (0)"
+    And I press "Disable messaging"
+    And I wait until the page is ready
+    And I should see "Successfully disabled messaging in 1 group(s)"
+    And I set the field "groups" to "Group-A-Test (0)"
+    And I press "Edit group settings"
+    Then the field "id_enablemessaging" matches value "0"
+
+  @javascript
+  Scenario: Messaging buttons are enabled when a group is selected
+    Given I set the field "groups" to "Group-A-Test (0)"
+    Then the field "groups" matches value "Group-A-Test (0)"
+    And the "Enable messaging" "button" should be enabled
+    And the "Disable messaging" "button" should be enabled

group/tests/behat/create_groups.feature

@@ -0,0 +1,153 @@
+@core @core_group
+Feature: Organize students into groups
+  In order to organize course activities in groups
+  As a teacher
+  I need to group students
+
+  @javascript
+  Scenario: Assign students to groups
+    Given the following "courses" exist:
+      | fullname | shortname | category | groupmode |
+      | Course 1 | C1 | 0 | 1 |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+      | student0 | Student | 0 | student0@example.com |
+      | student1 | Student | 1 | student1@example.com |
+      | student2 | Student | 2 | student2@example.com |
+      | student3 | Student | 3 | student3@example.com |
+    And the following "course enrolments" exist:
+      | user | course | role |
+      | teacher1 | C1 | editingteacher |
+      | student0 | C1 | student |
+      | student1 | C1 | student |
+      | student2 | C1 | student |
+      | student3 | C1 | student |
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group 1 |
+    And I press "Save changes"
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group 2 |
+    And I press "Save changes"
+    When I add "Student 0 (student0@example.com)" user to "Group 1" group members
+    And I add "Student 1 (student1@example.com)" user to "Group 1" group members
+    And I add "Student 2 (student2@example.com)" user to "Group 2" group members
+    And I add "Student 3 (student3@example.com)" user to "Group 2" group members
+    Then I set the field "groups" to "Group 1 (2)"
+    And the "members" select box should contain "Student 0 (student0@example.com)"
+    And the "members" select box should contain "Student 1 (student1@example.com)"
+    And the "members" select box should not contain "Student 2 (student2@example.com)"
+    And the "members" select box should not contain "Student 3 (student3@example.com)"
+    And I set the field "groups" to "Group 2 (2)"
+    And the "members" select box should contain "Student 2 (student2@example.com)"
+    And the "members" select box should contain "Student 3 (student3@example.com)"
+    And the "members" select box should not contain "Student 0 (student0@example.com)"
+    And the "members" select box should not contain "Student 1 (student1@example.com)"
+    And I navigate to course participants
+    And I set the field "type" in the "Filter 1" "fieldset" to "Groups"
+    And I set the field "Type or select..." in the "Filter 1" "fieldset" to "Group 1"
+    And I click on "Apply filters" "button"
+    And I should see "Student 0"
+    And I should see "Student 1"
+    And I should not see "Student 2"
+    And I set the field "Type or select..." in the "Filter 1" "fieldset" to "Group 2"
+    And I click on "Apply filters" "button"
+    And I should see "Student 2"
+    And I should see "Student 3"
+    And I should not see "Student 0"
+
+  @javascript
+  Scenario: Assign students to groups with site user identity configured
+    Given the following "courses" exist:
+      | fullname | shortname | groupmode |
+      | Course 1 | C1        | 1         |
+    And the following "users" exist:
+      | username | firstname | lastname | email               | country |
+      | teacher  | Teacher   | 1        | teacher@example.com | GB      |
+      | student  | Student   | 1        | student@example.com | DE      |
+    And the following "course enrolments" exist:
+      | user    | course | role           |
+      | teacher | C1     | editingteacher |
+      | student | C1     | student        |
+    And the following config values are set as admin:
+      | showuseridentity | email,country |
+    And I log in as "teacher"
+    And I am on the "Course 1" "groups" page
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group 1 |
+    And I press "Save changes"
+    When I add "Student 1 (student@example.com, DE)" user to "Group 1" group members
+    And I set the field "groups" to "Group 1 (1)"
+    Then the "members" select box should contain "Student 1 (student@example.com\, DE)"
+    # Non-AJAX version of the groups page.
+    And I press "Add/remove users"
+    And I press "Back to groups"
+    And the "members" select box should contain "Student 1 (student@example.com\, DE)"
+
+  Scenario: Create groups and groupings without the 'moodle/course:changeidnumber' capability
+    Given the following "courses" exist:
+      | fullname | shortname | category | groupmode |
+      | Course 1 | C1 | 0 | 1 |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+    And the following "course enrolments" exist:
+      | user | course | role |
+      | teacher1 | C1 | editingteacher |
+    And the following "role capability" exists:
+      | role                         | editingteacher |
+      | moodle/course:changeidnumber | prevent        |
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    When I press "Create group"
+    Then the "idnumber" "field" should be readonly
+    And I set the following fields to these values:
+      | Group name | The greatest group that never existed |
+    And I press "Save changes"
+    And I should see "The greatest group that never existed"
+    And I am on the "Course 1" "groupings" page
+    And I press "Create grouping"
+    And the "idnumber" "field" should be readonly
+    And I set the following fields to these values:
+      | Grouping name | Not the greatest grouping, but it's ok! |
+    And I press "Save changes"
+    And I should see "Not the greatest grouping, but it's ok!"
+
+  Scenario: Create groups with enrolment key
+    Given the following "courses" exist:
+      | fullname | shortname | category | groupmode |
+      | Course 1 | C1 | 0 | 1 |
+      | Course 2 | C2 | 0 | 1 |
+    And I log in as "admin"
+    And I am on the "Course 1" "groups" page
+    When I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group A |
+      | Enrolment key | badpasswd |
+    And I press "Save changes"
+    And I should see "Passwords must have at least 1 digit(s)"
+    And I set the following fields to these values:
+      | Group name | Group A |
+      | Enrolment key | Abcdef-1 |
+    And I press "Save changes"
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group B |
+      | Enrolment key | Abcdef-1 |
+    And I press "Save changes"
+    Then I should see "This enrolment key is already used for another group."
+    And I set the following fields to these values:
+      | Enrolment key | Abcdef-2 |
+    And I press "Save changes"
+    And the "groups" select box should contain "Group B (0)"
+    And I am on the "Course 2" "groups" page
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group A |
+      | Enrolment key | Abcdef-1 |
+    And I should not see "This enrolment key is already used for another group."

group/tests/behat/custom_fields.feature

@@ -0,0 +1,74 @@
+@core @core_group
+Feature: Custom profile fields in groups
+  In order to organize participants into groups
+  As a teacher
+  I need to be able to view and search on custom profile fields
+
+  Background:
+    Given the following "custom profile fields" exist:
+      | datatype | shortname | name    | param2 |
+      | text     | species   | Species | 255    |
+    And the following "users" exist:
+      | username | firstname | lastname | profile_field_species | email              |
+      | user1    | Robin     | Hood     | fox                   | email1@example.org |
+      | user2    | Little    | John     | bear                  | email2@example.org |
+    And the following "courses" exist:
+      | shortname | fullname |
+      | C1        | Course 1 |
+    And the following "course enrolments" exist:
+      | user  | course | role    |
+      | user1 | C1     | manager |
+      | user2 | C1     | manager |
+    And the following "groups" exist:
+      | name    | course | idnumber |
+      | Canines | C1     | G1       |
+    And the following "group members" exist:
+      | user  | group |
+      | user1 | G1    |
+    Given the following config values are set as admin:
+      | showuseridentity | username,profile_field_species |
+
+  @javascript
+  Scenario: Check the custom profile fields show up and can be searched on
+    When I am logged in as "admin"
+    And I am on the "Course 1" "groups" page
+
+    # Check the Overview page.
+    And I set the field "Participants tertiary navigation" to "Overview"
+    And "Robin Hood (user1, fox)" "text" should exist in the "Canines" "table_row"
+    And "Little John (user2, bear)" "text" should exist in the "No group" "table_row"
+
+    # Check the groups page.
+    And I set the field "Participants tertiary navigation" to "Groups"
+    And I set the field "groups" to "Canines"
+    And I should see "Robin Hood (user1, fox)"
+    And I should not see "Little John (user2, bear)"
+
+    # Check the members page.
+    And I press "Add/remove users"
+    And I should see "Robin Hood (user1, fox)"
+    And I should see "Little John (user2, bear)"
+
+    And I set the field "addselect" to "Little John (user2, bear)"
+    And I press "Add"
+    And I should see "Robin Hood (user1, fox)"
+    And I should see "Little John (user2, bear)"
+
+    And I set the field "Search" in the "#existingcell" "css_element" to "fox"
+    And I wait "1" seconds
+    And I should see "Robin Hood (user1, fox)"
+    And I should not see "Little John (user2, bear)"
+
+    And I set the field "Search" in the "#existingcell" "css_element" to ""
+    And I wait "1" seconds
+    And I set the field "removeselect" to "Little John (user2, bear)"
+    And I press "Remove"
+    And I set the field "removeselect" to "Robin Hood (user1, fox)"
+    And I press "Remove"
+    And I should see "Robin Hood (user1, fox)"
+    And I should see "Little John (user2, bear)"
+
+    And I set the field "Search" in the "#potentialcell" "css_element" to "bear"
+    And I wait "1" seconds
+    And I should see "Little John (user2, bear)"
+    And I should not see "Robin Hood (user1, fox)"

group/tests/behat/delete_groups.feature

@@ -0,0 +1,62 @@
+@core @core_group
+Feature: Automatic deletion of groups and groupings
+  In order to check the expected results occur when deleting groups and groupings in different scenarios
+  As a teacher
+  I need to create groups and groupings under different scenarios and check that the expected result occurs when attempting to delete them.
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | format |
+      | Course 1 | C1 | topics |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+    And the following "course enrolments" exist:
+      | user | course | role |
+      | teacher1 | C1 | editingteacher |
+    And the following "groups" exist:
+      | course | name               | idnumber |
+      | C1     | Group (without ID) |          |
+      | C1     | Group (with ID)    | An ID    |
+    And the following "groupings" exist:
+      | course | name                  | idnumber |
+      | C1     | Grouping (without ID) |          |
+      | C1     | Grouping (with ID)    | An ID    |
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page logged in as "teacher1"
+
+  @javascript
+  Scenario: Delete groups and groupings with and without ID numbers
+    Given I set the field "groups" to "Group (without ID) (0)"
+    And I press "Delete"
+    And I press "Yes"
+    Then the "groups" select box should not contain "Group (without ID) (0)"
+    And I set the field "groups" to "Group (with ID) (0)"
+    And I press "Delete"
+    And I press "Yes"
+    And the "groups" select box should not contain "Group (with ID) (0)"
+    And I set the field "Participants tertiary navigation" to "Groupings"
+    And I click on "Delete" "link" in the "Grouping (without ID)" "table_row"
+    And I press "Yes"
+    And I should not see "Grouping (without ID)"
+    And I click on "Delete" "link" in the "Grouping (with ID)" "table_row"
+    And I press "Yes"
+    And I should not see "Grouping (with ID)"
+
+  @javascript @skip_chrome_zerosize
+  Scenario: Delete groups and groupings with and without ID numbers without the 'moodle/course:changeidnumber' capability
+    Given the following "role capability" exists:
+      | role                         | editingteacher |
+      | moodle/course:changeidnumber | prevent        |
+    And I am on the "Course 1" "groups" page
+    When I set the field "groups" to "Group (with ID) (0)"
+    Then the "Delete" "button" should be disabled
+    And I set the field "groups" to "Group (without ID) (0)"
+    And I press "Delete"
+    And I press "Yes"
+    And I should not see "Group (without ID)"
+    And I set the field "Participants tertiary navigation" to "Groupings"
+    And "Delete" "link" should not exist in the "Grouping (with ID)" "table_row"
+    And I click on "Delete" "link" in the "Grouping (without ID)" "table_row"
+    And I press "Yes"
+    And I should not see "Grouping (without ID)"

group/tests/behat/group_customfields.feature

@@ -0,0 +1,73 @@
+@core @core_group @core_customfield @javascript
+Feature: Add and use group custom fields
+  In order to store an extra information about groups
+  As an admin
+  I need to create group customs fields and be able to populate them on group creation
+
+  Background:
+    Given the following "custom field categories" exist:
+      | name                   | component  | area     | itemid |
+      | Category for group1    | core_group | group    | 0      |
+      | Category for grouping1 | core_group | grouping | 0      |
+    And the following "courses" exist:
+      | fullname | shortname | category |
+      | Course 1 | C1 | 0 |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+    And the following "course enrolments" exist:
+      | user     | course | role           |
+      | teacher1 | C1     | editingteacher |
+
+  Scenario: Create a new group custom field and use the field for a new group
+    When I log in as "admin"
+    And I navigate to "Courses > Groups > Group custom fields" in site administration
+    Then I should see "Category for group1"
+    And I click on "Add a new custom field" "link"
+    And I click on "Short text" "link"
+    And I set the following fields to these values:
+      | Name       | Test field |
+      | Short name | testfield  |
+    And I click on "Save changes" "button" in the "Adding a new Short text" "dialogue"
+    Then the following should exist in the "generaltable" table:
+      | Custom field | Short name | Type       |
+      | Test field   | testfield  | Short text |
+    Then I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I press "Create group"
+    Then I should see "Category for group1"
+    And I should see "Test field"
+    And I set the following fields to these values:
+      | Group name  | My new group      |
+      | Test field  | Custom field text |
+    And I press "Save changes"
+    Then the "groups" select box should contain "My new group (0)"
+    And I set the field "groups" to "My new group (0)"
+    And I press "Edit group settings"
+    And the field "Test field" matches value "Custom field text"
+
+  Scenario: Create a new grouping custom field and use the field for a new grouping
+    When I log in as "admin"
+    And I navigate to "Courses > Groups > Grouping custom fields" in site administration
+    Then I should see "Category for grouping1"
+    And I click on "Add a new custom field" "link"
+    And I click on "Short text" "link"
+    And I set the following fields to these values:
+      | Name       | Test field |
+      | Short name | testfield  |
+    And I click on "Save changes" "button" in the "Adding a new Short text" "dialogue"
+    Then the following should exist in the "generaltable" table:
+      | Custom field | Short name | Type       |
+      | Test field   | testfield  | Short text |
+    Then I log in as "teacher1"
+    And I am on the "Course 1" "groupings" page
+    And I press "Create grouping"
+    Then I should see "Category for grouping1"
+    And I should see "Test field"
+    And I set the following fields to these values:
+      | Grouping name | My new grouping   |
+      | Test field    | Custom field text |
+    And I press "Save changes"
+    Then I should see "My new grouping"
+    And I click on "Edit" "link" in the "My new grouping" "table_row"
+    And the field "Test field" matches value "Custom field text"

group/tests/behat/group_description_picture.feature

@@ -0,0 +1,117 @@
+@core @core_group
+Feature: The description and picture of a group can be viewed by students and teachers
+  In order to view the description and picture of a group
+  As a teacher
+  I need to create groups and add descriptions and picture to them.
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | format |
+      | Course 1 | C1 | topics |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+      | student1 | Student | 1 | student1@example.com |
+      | student2 | Student | 2 | student2@example.com |
+    And the following "course enrolments" exist:
+      | user | course | role |
+      | teacher1 | C1 | editingteacher |
+      | student1 | C1 | student |
+      | student2 | C1 | student |
+
+  @javascript @_file_upload
+  Scenario: A student can see the group description and picture when visible groups are set. Teachers can see group details.
+    Given I am on the "Course 1" "course editing" page logged in as "teacher1"
+    And I set the following fields to these values:
+      | Group mode | Visible groups |
+    And I press "Save and display"
+    And I am on the "Course 1" "groups" page
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group A |
+      | Group description | Description for Group A |
+    # Upload group picture
+    And I upload "lib/tests/fixtures/gd-logo.png" file to "New picture" filemanager
+    And I press "Save changes"
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group B |
+    And I press "Save changes"
+    And I add "Student 1 (student1@example.com)" user to "Group A" group members
+    And I add "Student 2 (student2@example.com)" user to "Group B" group members
+    And I navigate to course participants
+    And I click on "Student 1" "link" in the "participants" "table"
+    And I click on "Group A" "link"
+    And I should see "Description for Group A"
+    # As teacher, confirm that group picture is displayed
+    And "//img[@class='grouppicture']" "xpath_element" should exist
+    And ".groupinfobox" "css_element" should exist
+    And I set the field "type" in the "Filter 1" "fieldset" to "Groups"
+    And I set the field "Type or select..." in the "Filter 1" "fieldset" to "Group B"
+    And I click on "Apply filters" "button"
+    And I click on "Student 2" "link" in the "participants" "table"
+    And I click on "Group B" "link"
+    And I should see "Student 2" in the "participants" "table"
+    And ".groupinfobox" "css_element" should not exist
+    When I am on the "Course 1" course page logged in as student1
+    And I navigate to course participants
+    And I click on "Student 1" "link" in the "participants" "table"
+    And I click on "Group A" "link"
+    # As student, confirm that group description and picture is displayed
+    Then I should see "Description for Group A"
+    And "//img[@class='grouppicture']" "xpath_element" should exist
+    And I am on the "Course 1" course page logged in as student2
+    And I navigate to course participants
+    And I click on "Student 2" "link" in the "participants" "table"
+    And I click on "Group B" "link"
+    And I should see "Student 2" in the "participants" "table"
+    And ".groupinfobox" "css_element" should not exist
+
+  @javascript @_file_upload
+  Scenario: A student can not see the group description and picture when separate groups are set. Teachers can see group details.
+    Given I am on the "Course 1" "course editing" page logged in as "teacher1"
+    And I set the following fields to these values:
+      | Group mode | Separate groups |
+    And I press "Save and display"
+    And I am on the "Course 1" "groups" page
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group A |
+      | Group description | Description for Group A |
+    # Upload group picture
+    And I upload "lib/tests/fixtures/gd-logo.png" file to "New picture" filemanager
+    And I press "Save changes"
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group B |
+    And I press "Save changes"
+    And I add "Student 1 (student1@example.com)" user to "Group A" group members
+    And I add "Student 2 (student2@example.com)" user to "Group B" group members
+    And I navigate to course participants
+    And I click on "Student 1" "link" in the "participants" "table"
+    And I click on "Group A" "link"
+    And I should see "Description for Group A"
+    # As teacher, confirm that group picture is displayed
+    And "//img[@class='grouppicture']" "xpath_element" should exist
+    And ".groupinfobox" "css_element" should exist
+    And I set the field "type" in the "Filter 1" "fieldset" to "Groups"
+    And I set the field "Type or select..." in the "Filter 1" "fieldset" to "Group B"
+    And I click on "Apply filters" "button"
+    And I click on "Student 2" "link" in the "participants" "table"
+    And I click on "Group B" "link"
+    And ".groupinfobox" "css_element" should not exist
+    When I am on the "Course 1" course page logged in as student1
+    And I navigate to course participants
+    And I click on "Student 1" "link" in the "participants" "table"
+    And I click on "Group A" "link"
+    And I should see "Student 1" in the "participants" "table"
+    # As student, confirm that group description and picture are not displayed
+    Then I should not see "Description for Group A"
+    And "//img[@class='grouppicture']" "xpath_element" should not exist
+    And ".groupinfobox" "css_element" should not exist
+    When I am on the "Course 1" course page logged in as student2
+    And I navigate to course participants
+    And I click on "Student 2" "link" in the "participants" "table"
+    And I click on "Group B" "link"
+    And I should see "Student 2" in the "participants" "table"
+    And ".groupinfobox" "css_element" should not exist

group/tests/behat/groups_import.feature

@@ -0,0 +1,180 @@
+@core @core_group @_file_upload
+Feature: Importing of groups and groupings
+  In order to import groups and grouping
+  As a teacher
+  I need to upload a file and verify groups and groupings can be imported
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | category |
+      | Course 1 | C1 | 0 |
+      | Course 2 | C2 | 0 |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+    And the following "course enrolments" exist:
+      | user | course | role |
+      | teacher1 | C1 | editingteacher |
+      | teacher1 | C2 | editingteacher |
+
+  @javascript
+  Scenario: Import groups and groupings as teacher
+    Given I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I press "Import groups"
+    When I upload "group/tests/fixtures/groups_import.csv" file to "Import" filemanager
+    And I press "Import groups"
+    And I press "Continue"
+    Then I should see "group-id-1"
+    And I should see "group-id-2"
+    And I should see "group-id-1-duplicate"
+    And I should see "group-noid-1"
+    And I should see "group-noid-2"
+    # Group messaging should have been enabled for group-id-1.
+    And I set the field "groups" to "group-id-1"
+    And I press "Edit group settings"
+    And I should see "Yes" in the "Group messaging" "select"
+    And I press "Cancel"
+     # Group messaging should not have been enabled for group-id-2.
+    And I set the field "groups" to "group-id-2"
+    And I press "Edit group settings"
+    And I should see "No" in the "Group messaging" "select"
+    And I press "Cancel"
+    # Check groupings
+    And I set the field "Participants tertiary navigation" to "Groupings"
+    And I should see "Grouping-1"
+    And I should see "Grouping-2"
+    And I should see "Grouping-3"
+    And I should see "group-id-1" in the "Grouping-1" "table_row"
+    And I should see "group-id-2" in the "Grouping-2" "table_row"
+    And I should see "group-noid-2" in the "Grouping-2" "table_row"
+    And I should see "group-id-1-duplicate" in the "Grouping-3" "table_row"
+    And I should see "group-noid-1" in the "Grouping-3" "table_row"
+
+  @javascript
+  Scenario: Import groups with idnumber when the user has proper permissions for the idnumber field
+    Given I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I press "Import groups"
+    When I upload "group/tests/fixtures/groups_import.csv" file to "Import" filemanager
+    And I press "Import groups"
+    Then I should see "Group group-id-1 added successfully"
+    And I should see "Group group-id-2 added successfully"
+    And I should see "group-id-1-duplicate: Group \"group-id-1\" with an idnumber of \"group-id-1\" already exists for this course"
+    And I should see "Group group-id-1-duplicate added successfully"
+    And I should see "Group group-noid-1 added successfully"
+    And I should see "Group group-noid-2 added successfully"
+    And I press "Continue"
+    And I set the field "groups" to "group-id-1"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value "group-id-1"
+    And I press "Cancel"
+    And I set the field "groups" to "group-id-2"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value "group-id-2"
+    And I press "Cancel"
+    And I set the field "groups" to "group-id-1-duplicate"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value ""
+    And I press "Cancel"
+    And I set the field "groups" to "group-noid-1"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value ""
+    And I press "Cancel"
+    And I set the field "groups" to "group-noid-2"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value ""
+    And I press "Cancel"
+
+  @javascript
+  Scenario: Import groups with idnumber when the user does not have proper permissions for the idnumber field
+    Given I log in as "admin"
+    And I am on the "Course 1" "permissions" page
+    And I override the system permissions of "Teacher" role with:
+      | moodle/course:changeidnumber | Prevent |
+    And I log out
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I press "Import groups"
+    When I upload "group/tests/fixtures/groups_import.csv" file to "Import" filemanager
+    And I press "Import groups"
+    And I press "Continue"
+    Then I set the field "groups" to "group-id-1"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value ""
+    And I press "Cancel"
+    And I set the field "groups" to "group-id-2"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value ""
+    And I press "Cancel"
+    And I set the field "groups" to "group-id-1-duplicate"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value ""
+    And I press "Cancel"
+    And I set the field "groups" to "group-noid-1"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value ""
+    And I press "Cancel"
+    And I set the field "groups" to "group-noid-2"
+    And I press "Edit group settings"
+    And the field "id_idnumber" matches value ""
+    And I press "Cancel"
+
+  @javascript
+  Scenario: Import groups into multiple courses as a teacher
+    Given I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I press "Import groups"
+    When I upload "group/tests/fixtures/groups_import_multicourse.csv" file to "Import" filemanager
+    And I press "Import groups"
+    Then I should see "Group group7 added successfully"
+    And I should see "Unknown course named \"C-non-existing\""
+    And I should see "Group group8 added successfully"
+    And I should not see "group-will-not-be-created"
+    And I should see "Group group9 added successfully"
+    And I should see "Group group10 added successfully"
+    And I press "Continue"
+    And I should see "group10"
+    And I should see "group7"
+    And I should see "group8"
+    And I should not see "group9"
+    And I should not see "group-will-not-be-created"
+    And I am on the "Course 2" "groups" page
+    And I should see "group9"
+    And I should not see "group-will-not-be-created"
+    And I should not see "group7"
+    And I should not see "group8"
+    And I should not see "group10"
+    And I log out
+
+  @javascript
+  Scenario: Import groups with custom field
+    Given the following "custom field categories" exist:
+      | name                   | component  | area     | itemid |
+      | Category for group1    | core_group | group    | 0      |
+      | Category for grouping1 | core_group | grouping | 0      |
+    And the following "custom fields" exist:
+      | name        | category               | type | shortname      |
+      | Test Field1 | Category for group1    | text | groupfield1    |
+      | Test Field2 | Category for grouping1 | text | groupingfield1 |
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I press "Import groups"
+    When I upload "group/tests/fixtures/groups_import_with_customfield.csv" file to "Import" filemanager
+    And I press "Import groups"
+    Then I should see "Group Group1 added successfully"
+    And I should see "Group Group2 added successfully"
+    And I should see "Grouping Grouping1 added successfully"
+    And I press "Continue"
+    And I set the field "groups" to "Group1 (0)"
+    And I press "Edit group settings"
+    And the field "Test Field1" matches value "Group1-Custom"
+    And I press "Cancel"
+    And I set the field "groups" to "Group2 (0)"
+    And I press "Edit group settings"
+    And the field "Test Field1" matches value "Group2-Custom"
+    And I press "Cancel"
+    And I am on the "Course 1" "groupings" page
+    Then I should see "Grouping1"
+    And I click on "Edit" "link" in the "Grouping1" "table_row"
+    And the field "Test Field2" matches value "Grouping1-Custom"

group/tests/behat/id_uniqueness.feature

@@ -0,0 +1,63 @@
+@core @core_group
+Feature: Uniqueness of Group ID number
+  In order to create unique groups and groupings
+  As a teacher
+  I need to create groups with unique identificators
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | category |
+      | Course 1 | C1 | 0 |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+    And the following "course enrolments" exist:
+      | user | course | role |
+      | teacher1 | C1 | editingteacher |
+
+  Scenario: Group ID number uniqueness
+    Given I am on the "Course 1" "groups" page logged in as "teacher1"
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group 1 |
+      | Group ID number | G1 |
+    And I press "Save changes"
+    When I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group 2 |
+      | Group ID number | G1 |
+    And I press "Save changes"
+    Then I should see "This ID number is already taken"
+    And I set the following fields to these values:
+      | Group ID number | G2 |
+    And I press "Save changes"
+    And I set the field "groups" to "Group 1 (0)"
+    And I press "Edit group settings"
+    And I set the following fields to these values:
+      | Group ID number | G2 |
+    And I press "Save changes"
+    And I should see "This ID number is already taken"
+    And I press "Cancel"
+
+  Scenario: Grouping ID number uniqueness
+    Given I am on the "Course 1" "groupings" page logged in as "teacher1"
+    And I press "Create grouping"
+    And I set the following fields to these values:
+      | Grouping name | Grouping 1 |
+      | Grouping ID number | GG1 |
+    And I press "Save changes"
+    When I press "Create grouping"
+    And I set the following fields to these values:
+      | Grouping name | Grouping 2 |
+      | Grouping ID number | GG1 |
+    And I press "Save changes"
+    Then I should see "This ID number is already taken"
+    And I set the following fields to these values:
+      | Grouping ID number | GG2 |
+    And I press "Save changes"
+    And I click on "Edit" "link" in the "Grouping 1" "table_row"
+    And I set the following fields to these values:
+      | Grouping ID number | GG2 |
+    And I press "Save changes"
+    And I should see "This ID number is already taken"
+    And I press "Cancel"

group/tests/behat/overview.feature

@@ -0,0 +1,199 @@
+@core @core_group
+Feature: Group overview
+  In order to view an overview of the groups
+  As a teacher
+  I need to visit the group overview page
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | category | groupmode |
+      | Course 1 | C1        | 0        | 1         |
+    And the following "users" exist:
+      | username | firstname | lastname | email                |
+      | teacher1 | Teacher   | 1        | teacher1@example.com |
+      | student0 | Student   | 0        | student0@example.com |
+      | student1 | Student   | 1        | student1@example.com |
+      | student2 | Student   | 2        | student2@example.com |
+      | student3 | Student   | 3        | student3@example.com |
+      | student4 | Student   | 4        | student4@example.com |
+      | student5 | Student   | 5        | student5@example.com |
+      | student6 | Student   | 6        | student6@example.com |
+      | student7 | Student   | 7        | student7@example.com |
+    And the following "course enrolments" exist:
+      | user     | course | role           |
+      | teacher1 | C1     | editingteacher |
+      | student0 | C1     | student        |
+      | student1 | C1     | student        |
+      | student2 | C1     | student        |
+      | student3 | C1     | student        |
+      | student4 | C1     | student        |
+      | student5 | C1     | student        |
+      | student6 | C1     | student        |
+      | student7 | C1     | student        |
+    And the following "groups" exist:
+      | name    | course | idnumber |
+      | Group 1 | C1     | G1       |
+      | Group 2 | C1     | G2       |
+      | Group 3 | C1     | G3       |
+      | Group 4 | C1     | G4       |
+    And the following "group members" exist:
+      | user     | group |
+      | student0 | G1    |
+      | student1 | G1    |
+      | student2 | G2    |
+      | student3 | G3    |
+      | student4 | G3    |
+      | student5 | G4    |
+    And the following "groupings" exist:
+      | name       | course | idnumber |
+      | Grouping 1 | C1     | GG1      |
+      | Grouping 2 | C1     | GG2      |
+    And the following "grouping groups" exist:
+      | grouping | group |
+      | GG1      | G1    |
+      | GG1      | G2    |
+      | GG2      | G2    |
+      | GG2      | G3    |
+
+  Scenario: Filter the overview in various different ways
+    Given I am on the "Course 1" "groups overview" page logged in as "teacher1"
+    # Grouping All and Group All filter
+    When I select "All" from the "Grouping" singleselect
+    And I select "All" from the "group" singleselect
+    # Following groups should exist in groupings.
+    Then the group overview should include groups "Group 1, Group 2" in grouping "Grouping 1"
+    And the group overview should include groups "Group 2,Group 3" in grouping "Grouping 2"
+    And the group overview should include groups "Group 4" in grouping "Not in a grouping"
+    And the group overview should include groups "No group" in grouping "Not in a group"
+    # Following members should exit in group.
+    And "Student 0" "text" should exist in the "Group 1" "table_row"
+    And "Student 1" "text" should exist in the "Group 1" "table_row"
+    And "Student 2" "text" should exist in the "Group 2" "table_row"
+    And "Student 3" "text" should exist in the "Group 3" "table_row"
+    And "Student 4" "text" should exist in the "Group 3" "table_row"
+    And "Student 5" "text" should exist in the "Group 4" "table_row"
+    And "Student 6" "text" should exist in the "No group" "table_row"
+    And "Student 7" "text" should exist in the "No group" "table_row"
+
+    # Grouping 1 and Group All filter
+    And I select "Grouping 1" from the "Grouping" singleselect
+    And I select "All" from the "group" singleselect
+    # Following groups should exist in groupings.
+    And the group overview should include groups "Group 1, Group 2" in grouping "Grouping 1"
+    # Following groups should not exits
+    And "Group 3" "table_row" should not exist
+    And "No group" "table_row" should not exist
+    # Following members should exit in group.
+    And "Student 0" "text" should exist in the "Group 1" "table_row"
+    And "Student 1" "text" should exist in the "Group 1" "table_row"
+    And "Student 2" "text" should exist in the "Group 2" "table_row"
+    # Following members should not exit in group.
+    And I should not see "Student 3"
+    And I should not see "Student 4"
+    And I should not see "Student 5"
+    And I should not see "Student 6"
+    And I should not see "Student 7"
+
+    # Grouping 2 and Group All filter
+    And I select "Grouping 2" from the "Grouping" singleselect
+    And I select "All" from the "group" singleselect
+    # Following groups should exist in groupings.
+    And the group overview should include groups "Group 2, Group 3" in grouping "Grouping 2"
+    # Following groups should not exits
+    And "Group 1" "table_row" should not exist
+    And "No group" "table_row" should not exist
+    # Following members should exit in group.
+    And "Student 2" "text" should exist in the "Group 2" "table_row"
+    And "Student 3" "text" should exist in the "Group 3" "table_row"
+    And "Student 4" "text" should exist in the "Group 3" "table_row"
+    # Following members should not exit in group.
+    And I should not see "Student 0"
+    And I should not see "Student 1"
+    And I should not see "Student 5"
+    And I should not see "Student 6"
+    And I should not see "Student 7"
+
+    # No grouping and Group All filter
+    And I select "No grouping" from the "Grouping" singleselect
+    And I select "All" from the "group" singleselect
+    # Following groups should exist in groupings.
+    And the group overview should include groups "Group 4" in grouping "Not in a grouping"
+    And the group overview should include groups "No group" in grouping "Not in a group"
+    # Following groups should not exits
+    And "Group 1" "table_row" should not exist
+    And "Group 2" "table_row" should not exist
+    And "Group 3" "table_row" should not exist
+    # Following members should exit in group.
+    And "Student 5" "text" should exist in the "Group 4" "table_row"
+    And "Student 6" "text" should exist in the "No group" "table_row"
+    And "Student 7" "text" should exist in the "No group" "table_row"
+    # Following members should not exit in group.
+    And I should not see "Student 0"
+    And I should not see "Student 1"
+    And I should not see "Student 2"
+    And I should not see "Student 3"
+    And I should not see "Student 4"
+
+    # Grouping All and Group 1 filter
+    And I select "All" from the "Grouping" singleselect
+    And I select "Group 1" from the "group" singleselect
+    # Following groups should exist in groupings.
+    And the group overview should include groups "Group 1" in grouping "Grouping 1"
+    # Following groups should not exits
+    And "Group 2" "table_row" should not exist
+    And "Group 3" "table_row" should not exist
+    And "Group 4" "table_row" should not exist
+    And "No group" "table_row" should not exist
+    # Following members should exit in group.
+    And "Student 0" "text" should exist in the "Group 1" "table_row"
+    And "Student 1" "text" should exist in the "Group 1" "table_row"
+    # Following members should not exit in group.
+    And I should not see "Student 2"
+    And I should not see "Student 3"
+    And I should not see "Student 4"
+    And I should not see "Student 5"
+    And I should not see "Student 6"
+    And I should not see "Student 7"
+
+    # Grouping All and Group 2 filter
+    And I select "All" from the "Grouping" singleselect
+    And I select "Group 2" from the "group" singleselect
+    # Following groups should exist in groupings.
+    And the group overview should include groups "Group 2" in grouping "Grouping 1"
+    And the group overview should include groups "Group 2" in grouping "Grouping 2"
+    # Following groups should not exits
+    And "Group 1" "table_row" should not exist
+    And "Group 3" "table_row" should not exist
+    And "Group 4" "table_row" should not exist
+    And "No group" "table_row" should not exist
+    # Following members should exit in group.
+    And "Student 2" "text" should exist in the "Group 2" "table_row"
+    # Following members should not exit in group.
+    And I should not see "Student 0"
+    And I should not see "Student 1"
+    And I should not see "Student 3"
+    And I should not see "Student 4"
+    And I should not see "Student 5"
+    And I should not see "Student 6"
+    And I should not see "Student 7"
+
+    # Grouping All and No group filter
+    And I select "All" from the "Grouping" singleselect
+    And I select "No group" from the "group" singleselect
+    # Following groups should exist in groupings.
+    And the group overview should include groups "No group" in grouping "Not in a group"
+    # Following groups should not exits
+    And "Group 1" "table_row" should not exist
+    And "Group 2" "table_row" should not exist
+    And "Group 3" "table_row" should not exist
+    And "Group 4" "table_row" should not exist
+    # Following members should exit in group.
+    And "Student 6" "text" should exist in the "No group" "table_row"
+    And "Student 7" "text" should exist in the "No group" "table_row"
+    # Following members should not exit in group.
+    And I should not see "Student 0"
+    And I should not see "Student 1"
+    And I should not see "Student 2"
+    And I should not see "Student 3"
+    And I should not see "Student 4"
+    And I should not see "Student 5"

group/tests/behat/private_groups.feature

@@ -0,0 +1,176 @@
+@core @core_group
+Feature: Private groups
+  As a teacher
+  In order to organise students into groups while protecting their privacy
+  I want to define groups that are not visible to all students
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | format | enablecompletion | numsections |
+      | Course 1 | C1        | topics | 1                | 3           |
+    And the following "users" exist:
+      | username | firstname | lastname |
+      | teacher1 | Teacher   | Teacher  |
+      | student1 | Student   | 1        |
+      | student2 | Student   | 2        |
+      | student3 | Student   | 3        |
+      | student4 | Student   | 4        |
+      | student5 | Student   | 5        |
+      | student6 | Student   | 6        |
+      | student7 | Student   | 7        |
+      | student8 | Student   | 8        |
+    And the following "course enrolments" exist:
+      | user     | course | role           |
+      | teacher1 | C1     | editingteacher |
+      | student1 | C1     | student        |
+      | student2 | C1     | student        |
+      | student3 | C1     | student        |
+      | student4 | C1     | student        |
+      | student5 | C1     | student        |
+      | student6 | C1     | student        |
+      | student7 | C1     | student        |
+      | student8 | C1     | student        |
+    And the following "groups" exist:
+      | name                                      | course | idnumber | visibility | participation |
+      | Visible/Participation                     | C1     | VP       | 0          | 1             |
+      | Only visible to members/Participation     | C1     | MP       | 1          | 1             |
+      | Only see own membership                   | C1     | O        | 2          | 0             |
+      | Not visible                               | C1     | N        | 3          | 0             |
+      | Visible/Non-Participation                 | C1     | VN       | 0          | 0             |
+      | Only visible to members/Non-Participation | C1     | MN       | 1          | 0             |
+    And the following "group members" exist:
+      | user     | group |
+      | student1 | VP    |
+      | student1 | VN    |
+      | student2 | MP    |
+      | student2 | MN    |
+      | student3 | O     |
+      | student4 | N     |
+      | student5 | VP    |
+      | student5 | VN    |
+      | student6 | MP    |
+      | student6 | MN    |
+      | student7 | O     |
+      | student8 | N     |
+
+  Scenario: Participants in "Visible" groups see their membership and other members:
+    Given I am on the "C1" "enrolled users" page logged in as "student1"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups                                                         |
+      | Student 1            | Visible/Non-Participation, Visible/Participation               |
+      | Student 2            | No groups                                                      |
+      | Student 3            | No groups                                                      |
+      | Student 4            | No groups                                                      |
+      | Student 5            | Visible/Non-Participation, Visible/Participation               |
+      | Student 6            | No groups                                                      |
+      | Student 7            | No groups                                                      |
+      | Student 8            | No groups                                                      |
+
+  Scenario: Participants in "Only visible to members" groups see their membership and other members, plus "Visible"
+    Given I am on the "C1" "enrolled users" page logged in as "student2"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups                                                                 |
+      | Student 1            | Visible/Non-Participation, Visible/Participation                       |
+      | Student 2            | Only visible to members/Non-Participation, Only visible to members/Participation |
+      | Student 3            | No groups                                                              |
+      | Student 4            | No groups                                                              |
+      | Student 5            | Visible/Non-Participation, Visible/Participation                       |
+      | Student 6            | Only visible to members/Non-Participation, Only visible to members/Participation |
+      | Student 7            | No groups                                                              |
+      | Student 8            | No groups                                                              |
+
+  Scenario: Participants in "Only see own membership" groups see their membership but not other members, plus "Visible"
+    Given I am on the "C1" "enrolled users" page logged in as "student3"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups                                                                 |
+      | Student 1            | Visible/Non-Participation, Visible/Participation                       |
+      | Student 2            | No groups                                                              |
+      | Student 3            | Only see own membership                                                     |
+      | Student 4            | No groups                                                              |
+      | Student 5            | Visible/Non-Participation, Visible/Participation                       |
+      | Student 6            | No groups                                                              |
+      | Student 7            | No groups                                                              |
+      | Student 8            | No groups                                                              |
+
+  Scenario: Participants in "Not visible" groups do not see that group, do see "Visible"
+    Given I am on the "C1" "enrolled users" page logged in as "student4"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups                                                                 |
+      | Student 1            | Visible/Non-Participation, Visible/Participation                       |
+      | Student 2            | No groups                                                              |
+      | Student 3            | No groups                                                              |
+      | Student 4            | No groups                                                              |
+      | Student 5            | Visible/Non-Participation, Visible/Participation                       |
+      | Student 6            | No groups                                                              |
+      | Student 7            | No groups                                                              |
+      | Student 8            | No groups                                                              |
+
+  Scenario: View participants list as a teacher:
+    Given I am on the "C1" "enrolled users" page logged in as "teacher1"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups                                                                 |
+      | Student 1            | Visible/Non-Participation, Visible/Participation                       |
+      | Student 2            | Only visible to members/Non-Participation, Only visible to members/Participation |
+      | Student 3            | Only see own membership                                                     |
+      | Student 4            | Not visible                                                            |
+      | Student 5            | Visible/Non-Participation, Visible/Participation                       |
+      | Student 6            | Only visible to members/Non-Participation, Only visible to members/Participation |
+      | Student 7            | Only see own membership                                                     |
+      | Student 8            | Not visible                                                            |
+
+  @javascript
+  Scenario: Filtering by "Only see own membership" groups should not show other members.
+    Given I am on the "C1" "enrolled users" page logged in as "student3"
+    When I set the field "type" to "Groups"
+    And I set the field "Type or select..." to "Only see own membership"
+    And I click on "Apply filters" "button"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups                  |
+      | Student 3            | Only see own membership |
+    And the following should not exist in the "participants" table:
+      | First name           | Groups                  |
+      | Student 7            | No groups               |
+
+  @javascript
+  Scenario: Filtering by "No group" should show all users whose memberships I cannot see
+    Given I am on the "C1" "enrolled users" page logged in as "student3"
+    When I set the field "type" to "Groups"
+    And I set the field "Type or select..." to "No group"
+    And I click on "Apply filters" "button"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups     |
+      | Student 2            | No groups  |
+      | Student 4            | No groups  |
+      | Student 6            | No groups  |
+      | Student 7            | No groups  |
+      | Student 8            | No groups  |
+
+  @javascript
+  Scenario: Filtering by not a member of "Only see own membership" groups I am a member of should show everyone except me
+    Given I am on the "C1" "enrolled users" page logged in as "student3"
+    When I set the field "Match" in the "Filter 1" "fieldset" to "None"
+    And I set the field "type" to "Groups"
+    And I set the field "Type or select..." to "Only see own membership"
+    And I click on "Apply filters" "button"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups                                                                   |
+      | Student 1            | Visible/Non-Participation, Visible/Participation                         |
+      | Student 2            | No groups                                                                |
+      | Student 4            | No groups                                                                |
+      | Student 5            | Visible/Non-Participation, Visible/Participation                         |
+      | Student 6            | No groups                                                                |
+      | Student 7            | No groups                                                                |
+      | Student 8            | No groups                                                                |
+
+  @javascript
+  Scenario: Filtering by not a member of "No group" should only show users whose memberships I can see
+    Given I am on the "C1" "enrolled users" page logged in as "student3"
+    When I set the field "Match" in the "Filter 1" "fieldset" to "None"
+    And I set the field "type" to "Groups"
+    And I set the field "Type or select..." to "No group"
+    And I click on "Apply filters" "button"
+    Then the following should exist in the "participants" table:
+      | First name           | Groups                                                                   |
+      | Student 1            | Visible/Non-Participation, Visible/Participation                         |
+      | Student 3            | Only see own membership                                                  |
+      | Student 5            | Visible/Non-Participation, Visible/Participation                         |

group/tests/behat/role_visibility.feature

@@ -0,0 +1,50 @@
+@core @core_group
+Feature: Test role visibility for the groups management page
+  In order to control access
+  As an admin
+  I need to control which roles can see each other
+
+  Background: Set up some groups
+    Given  the following "courses" exist:
+      | fullname | shortname |
+      | Course 1 | C1        |
+    And the following "users" exist:
+      | username | firstname | lastname | email                |
+      | learner1 | Learner   | 1        | learner1@example.com |
+      | teacher1 | Teacher   | 1        | teacher1@example.com |
+      | manager1 | Manager   | 1        | manager1@example.com |
+    And the following "course enrolments" exist:
+      | user     | course | role           |
+      | learner1 | C1     | student        |
+      | teacher1 | C1     | editingteacher |
+      | manager1 | C1     | manager        |
+    And the following "groups" exist:
+      | name    | course | idnumber |
+      | Group 1 | C1     | G1       |
+    And the following "group members" exist:
+      | user     | group |
+      | learner1 | G1    |
+      | teacher1 | G1    |
+      | manager1 | G1    |
+
+  Scenario: Check the default roles are visible
+    Given I log in as "manager1"
+    And I am on the "Course 1" "groups" page
+    When I set the field "groups" to "Group 1 (3)"
+    And I press "Show members for group"
+    Then "optgroup[label='No roles']" "css_element" should not exist in the "#members" "css_element"
+    And "optgroup[label='Student']" "css_element" should exist in the "#members" "css_element"
+    And "optgroup[label='Teacher']" "css_element" should exist in the "#members" "css_element"
+    And "optgroup[label='Manager']" "css_element" should exist in the "#members" "css_element"
+    And I log out
+
+  Scenario: Do not allow managers to view any roles and check they are hidden
+    Given I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    When I set the field "groups" to "Group 1 (3)"
+    And I press "Show members for group"
+    Then "optgroup[label='No roles']" "css_element" should exist in the "#members" "css_element"
+    And "optgroup[label='Student']" "css_element" should exist in the "#members" "css_element"
+    And "optgroup[label='Teacher']" "css_element" should exist in the "#members" "css_element"
+    And "optgroup[label='Manager']" "css_element" should not exist in the "#members" "css_element"
+    And I log out

group/tests/behat/update_groups.feature

@@ -0,0 +1,159 @@
+@core @core_group
+Feature: Automatic updating of groups and groupings
+  In order to check the expected results occur when updating groups and groupings in different scenarios
+  As a teacher
+  I need to create groups and groupings under different scenarios and check that the expected result occurs when attempting to update them.
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname | format |
+      | Course 1 | C1 | topics |
+    And the following "users" exist:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@example.com |
+    And the following "course enrolments" exist:
+      | user | course | role |
+      | teacher1 | C1 | editingteacher |
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group (without ID) |
+    And I press "Save changes"
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group (with ID) |
+      | Group ID number | An ID |
+    And I press "Save changes"
+    And I set the field "Participants tertiary navigation" to "Groupings"
+    And I press "Create grouping"
+    And I set the following fields to these values:
+      | Grouping name | Grouping (without ID) |
+    And I press "Save changes"
+    And I press "Create grouping"
+    And I set the following fields to these values:
+      | Grouping name | Grouping (with ID) |
+      | Grouping ID number | An ID |
+    And I press "Save changes"
+    And I set the field "Participants tertiary navigation" to "Groups"
+
+  @javascript
+  Scenario: Update groups and groupings with ID numbers
+    Given I set the field "groups" to "Group (with ID)"
+    And I press "Edit group settings"
+    And the field "idnumber" matches value "An ID"
+    And I set the following fields to these values:
+      | Group name | Group (with ID) (updated) |
+      | Group ID number | An ID (updated) |
+    When I press "Save changes"
+    Then I should see "Group (with ID) (updated)"
+    And I set the field "groups" to "Group (with ID) (updated)"
+    And I press "Edit group settings"
+    And the field "idnumber" matches value "An ID (updated)"
+    And I press "Save changes"
+    And I set the field "Participants tertiary navigation" to "Groupings"
+    And I click on "Edit" "link" in the "Grouping (with ID)" "table_row"
+    And the field "idnumber" matches value "An ID"
+    And I set the following fields to these values:
+      | Grouping name | Grouping (with ID) (updated) |
+      | Grouping ID number | An ID (updated) |
+    And I press "Save changes"
+    And I should see "Grouping (with ID) (updated)"
+    And I click on "Edit" "link" in the "Grouping (with ID) (updated)" "table_row"
+    And the field "idnumber" matches value "An ID (updated)"
+
+  @javascript @skip_chrome_zerosize
+  Scenario: Update groups and groupings with ID numbers without the 'moodle/course:changeidnumber' capability
+    Given the following "role capability" exists:
+      | role                         | editingteacher |
+      | moodle/course:changeidnumber | prevent        |
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I set the field "groups" to "Group (with ID)"
+    When I press "Edit group settings"
+    Then the "idnumber" "field" should be readonly
+    And the field "idnumber" matches value "An ID"
+    And I set the following fields to these values:
+      | Group name | Group (with ID) (updated) |
+    And I press "Save changes"
+    And I should see "Group (with ID) (updated)"
+    And I set the field "groups" to "Group (with ID) (updated)"
+    And I press "Edit group settings"
+    And the "idnumber" "field" should be readonly
+    And the field "idnumber" matches value "An ID"
+    And I press "Save changes"
+    And I set the field "Participants tertiary navigation" to "Groupings"
+    And I click on "Edit" "link" in the "Grouping (with ID)" "table_row"
+    And the "idnumber" "field" should be readonly
+    And the field "idnumber" matches value "An ID"
+    And I set the following fields to these values:
+      | Grouping name | Grouping (with ID) (updated) |
+    And I press "Save changes"
+    And I should see "Grouping (with ID) (updated)"
+    And I click on "Edit" "link" in the "Grouping (with ID) (updated)" "table_row"
+    And the "idnumber" "field" should be readonly
+    And the field "idnumber" matches value "An ID"
+
+  @javascript
+  Scenario: Update groups with enrolment key
+    Given the following "courses" exist:
+      | fullname | shortname |
+      | Course 2 | C2 |
+    And the following "course enrolments" exist:
+      | user | course | role |
+      | teacher1 | C2 | editingteacher |
+    And I log out
+    And I log in as "teacher1"
+    And I am on the "Course 1" "groups" page
+    And I set the field "groups" to "Group (with ID)"
+    And I press "Edit group settings"
+    And I set the following fields to these values:
+      | Enrolment key | badpasswd |
+    When I press "Save changes"
+    Then I should see "Passwords must have at least 1 digit(s)"
+    And I set the following fields to these values:
+      | Enrolment key | Abcdef-1 |
+    And I press "Save changes"
+    And I set the field "groups" to "Group (with ID)"
+    And I press "Edit group settings"
+    And I press "Save changes"
+    And I should not see "This enrolment key is already used for another group."
+    And I set the field "groups" to "Group (without ID)"
+    And I press "Edit group settings"
+    And I set the following fields to these values:
+      | Enrolment key | Abcdef-1 |
+    And I press "Save changes"
+    And I should see "This enrolment key is already used for another group."
+    And I set the following fields to these values:
+      | Enrolment key | Abcdef-2 |
+    And I press "Save changes"
+    And I should not see "This enrolment key is already used for another group."
+    And I am on the "Course 2" "groups" page
+    And I press "Create group"
+    And I set the following fields to these values:
+      | Group name | Group A |
+    And I press "Save changes"
+    And I should not see "This enrolment key is already used for another group."
+    And I set the field "groups" to "Group A"
+    And I press "Edit group settings"
+    And I set the following fields to these values:
+      | Enrolment key | Abcdef-1 |
+    And I press "Save changes"
+    And I should not see "This enrolment key is already used for another group."
+
+  @javascript
+  Scenario: Visibility and Participation settings are locked once a group has members
+    Given I set the field "groups" to "Group (with ID)"
+    And I press "Edit group settings"
+    And "visibility" "select" should exist
+    And the field "Group membership visibility" matches value "Visible"
+    And the "participation" "checkbox" should be enabled
+    And the field "Show group in dropdown menu for activities in group mode" matches value "1"
+    When the following "group members" exist:
+      | user     | group |
+      | teacher1 | An ID |
+    And I reload the page
+    Then "visibility" "select" should not exist
+    And "Visible" "text" should exist
+    And the "participation" "checkbox" should be disabled
+    And the field "Show group in dropdown menu for activities in group mode" matches value "1"

group/tests/customfield/group_handler_test.php

@@ -0,0 +1,186 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\customfield;
+
+use advanced_testcase;
+use context_course;
+use context_system;
+use moodle_url;
+use core_customfield\field_controller;
+
+/**
+ * Unit tests for group custom field handler.
+ *
+ * @package   core_group
+ * @covers    \core_group\customfield\group_handler
+ * @author    Tomo Tsuyuki <tomotsuyuki@catalyst-au.net>
+ * @copyright 2023 Catalyst IT Pty Ltd
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class group_handler_test extends advanced_testcase {
+    /**
+     * Test custom field handler.
+     * @var group_handler
+     */
+    protected $handler;
+
+    /**
+     * Setup.
+     */
+    public function setUp(): void {
+        $this->handler = group_handler::create();
+    }
+
+    /**
+     * Create group custom field for testing.
+     *
+     * @return field_controller
+     */
+    protected function create_group_custom_field(): field_controller {
+        $fieldcategory = self::getDataGenerator()->create_custom_field_category([
+            'component' => 'core_group',
+            'area' => 'group',
+        ]);
+
+        return self::getDataGenerator()->create_custom_field([
+            'shortname' => 'testfield1',
+            'type' => 'text',
+            'categoryid' => $fieldcategory->get('id'),
+        ]);
+    }
+
+    /**
+     * Test configuration context.
+     */
+    public function test_get_configuration_context(): void {
+        $this->assertInstanceOf(context_system::class, $this->handler->get_configuration_context());
+    }
+
+    /**
+     * Test getting config URL.
+     */
+    public function test_get_configuration_url(): void {
+        $this->assertInstanceOf(moodle_url::class, $this->handler->get_configuration_url());
+        $this->assertEquals('/group/customfield.php', $this->handler->get_configuration_url()->out_as_local_url());
+    }
+
+    /**
+     * Test getting instance context.
+     */
+    public function test_get_instance_context(): void {
+        global $COURSE;
+        $this->resetAfterTest();
+
+        $course = self::getDataGenerator()->create_course();
+        $group = self::getDataGenerator()->create_group(['courseid' => $course->id]);
+
+        $this->assertInstanceOf(context_course::class, $this->handler->get_instance_context());
+        $this->assertSame(context_course::instance($COURSE->id), $this->handler->get_instance_context());
+
+        $this->assertInstanceOf(context_course::class, $this->handler->get_instance_context($group->id));
+        $this->assertSame(context_course::instance($course->id), $this->handler->get_instance_context($group->id));
+    }
+
+    /**
+     * Test can configure check.
+     */
+    public function test_can_configure(): void {
+        $this->resetAfterTest();
+
+        $user = self::getDataGenerator()->create_user();
+        self::setUser($user);
+
+        $this->assertFalse($this->handler->can_configure());
+
+        $roleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/group:configurecustomfields', CAP_ALLOW, $roleid, context_system::instance()->id, true);
+        role_assign($roleid, $user->id, context_system::instance()->id);
+
+        $this->assertTrue($this->handler->can_configure());
+    }
+
+    /**
+     * Test can edit functionality.
+     */
+    public function test_can_edit(): void {
+        $this->resetAfterTest();
+
+        $course = self::getDataGenerator()->create_course();
+        $contextid = context_course::instance($course->id)->id;
+        $group = self::getDataGenerator()->create_group(['courseid' => $course->id]);
+        $roleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/course:managegroups', CAP_ALLOW, $roleid, $contextid, true);
+
+        $field = $this->create_group_custom_field();
+
+        $user = self::getDataGenerator()->create_user();
+        self::setUser($user);
+
+        $this->assertFalse($this->handler->can_edit($field, $group->id));
+
+        role_assign($roleid, $user->id, $contextid);
+        $this->assertTrue($this->handler->can_edit($field, $group->id));
+    }
+
+    /**
+     * Test can view functionality.
+     */
+    public function test_can_view(): void {
+        $this->resetAfterTest();
+
+        $course = self::getDataGenerator()->create_course();
+        $contextid = context_course::instance($course->id)->id;
+        $group = self::getDataGenerator()->create_group(['courseid' => $course->id]);
+        $manageroleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/course:managegroups', CAP_ALLOW, $manageroleid, $contextid, true);
+
+        $viewroleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/course:view', CAP_ALLOW, $viewroleid, $contextid, true);
+
+        $viewandmanageroleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/course:managegroups', CAP_ALLOW, $viewandmanageroleid, $contextid, true);
+        assign_capability('moodle/course:view', CAP_ALLOW, $viewandmanageroleid, $contextid, true);
+
+        $field = $this->create_group_custom_field();
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+        $user3 = self::getDataGenerator()->create_user();
+
+        self::setUser($user1);
+        $this->assertFalse($this->handler->can_view($field, $group->id));
+
+        self::setUser($user2);
+        $this->assertFalse($this->handler->can_view($field, $group->id));
+
+        self::setUser($user3);
+        $this->assertFalse($this->handler->can_view($field, $group->id));
+
+        role_assign($manageroleid, $user1->id, $contextid);
+        role_assign($viewroleid, $user2->id, $contextid);
+        role_assign($viewandmanageroleid, $user3->id, $contextid);
+
+        self::setUser($user1);
+        $this->assertTrue($this->handler->can_view($field, $group->id));
+
+        self::setUser($user2);
+        $this->assertTrue($this->handler->can_view($field, $group->id));
+
+        self::setUser($user3);
+        $this->assertTrue($this->handler->can_view($field, $group->id));
+    }
+}

group/tests/customfield/grouping_handler_test.php

@@ -0,0 +1,186 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_group\customfield;
+
+use advanced_testcase;
+use context_course;
+use context_system;
+use moodle_url;
+use core_customfield\field_controller;
+
+/**
+ * Unit tests for grouping custom field handler.
+ *
+ * @package   core_group
+ * @covers    \core_group\customfield\group_handler
+ * @author    Tomo Tsuyuki <tomotsuyuki@catalyst-au.net>
+ * @copyright 2023 Catalyst IT Pty Ltd
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class grouping_handler_test extends advanced_testcase {
+    /**
+     * Test custom field handler.
+     * @var \core_customfield\handler
+     */
+    protected $handler;
+
+    /**
+     * Setup.
+     */
+    public function setUp(): void {
+        $this->handler = grouping_handler::create();
+    }
+
+    /**
+     * Create grouping custom field for testing.
+     *
+     * @return field_controller
+     */
+    protected function create_grouping_custom_field(): field_controller {
+        $fieldcategory = self::getDataGenerator()->create_custom_field_category([
+            'component' => 'core_group',
+            'area' => 'grouping',
+        ]);
+
+        return self::getDataGenerator()->create_custom_field([
+            'shortname' => 'testfield1',
+            'type' => 'text',
+            'categoryid' => $fieldcategory->get('id'),
+        ]);
+    }
+
+    /**
+     * Test configuration context.
+     */
+    public function test_get_configuration_context(): void {
+        $this->assertInstanceOf(context_system::class, $this->handler->get_configuration_context());
+    }
+
+    /**
+     * Test getting config URL.
+     */
+    public function test_get_configuration_url(): void {
+        $this->assertInstanceOf(moodle_url::class, $this->handler->get_configuration_url());
+        $this->assertEquals('/group/grouping_customfield.php', $this->handler->get_configuration_url()->out_as_local_url());
+    }
+
+    /**
+     * Test getting instance context.
+     */
+    public function test_get_instance_context(): void {
+        global $COURSE;
+        $this->resetAfterTest();
+
+        $course = self::getDataGenerator()->create_course();
+        $grouping = self::getDataGenerator()->create_grouping(['courseid' => $course->id]);
+
+        $this->assertInstanceOf(context_course::class, $this->handler->get_instance_context());
+        $this->assertSame(context_course::instance($COURSE->id), $this->handler->get_instance_context());
+
+        $this->assertInstanceOf(context_course::class, $this->handler->get_instance_context($grouping->id));
+        $this->assertSame(context_course::instance($course->id), $this->handler->get_instance_context($grouping->id));
+    }
+
+    /**
+     * Test can configure check.
+     */
+    public function test_can_configure(): void {
+        $this->resetAfterTest();
+
+        $user = self::getDataGenerator()->create_user();
+        self::setUser($user);
+
+        $this->assertFalse($this->handler->can_configure());
+
+        $roleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/group:configurecustomfields', CAP_ALLOW, $roleid, context_system::instance()->id, true);
+        role_assign($roleid, $user->id, context_system::instance()->id);
+
+        $this->assertTrue($this->handler->can_configure());
+    }
+
+    /**
+     * Test can edit functionality.
+     */
+    public function test_can_edit(): void {
+        $this->resetAfterTest();
+
+        $course = self::getDataGenerator()->create_course();
+        $contextid = context_course::instance($course->id)->id;
+        $grouping = self::getDataGenerator()->create_grouping(['courseid' => $course->id]);
+        $roleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/course:managegroups', CAP_ALLOW, $roleid, $contextid, true);
+
+        $field = $this->create_grouping_custom_field();
+
+        $user = self::getDataGenerator()->create_user();
+        self::setUser($user);
+
+        $this->assertFalse($this->handler->can_edit($field, $grouping->id));
+
+        role_assign($roleid, $user->id, $contextid);
+        $this->assertTrue($this->handler->can_edit($field, $grouping->id));
+    }
+
+    /**
+     * Test can view functionality.
+     */
+    public function test_can_view(): void {
+        $this->resetAfterTest();
+
+        $course = self::getDataGenerator()->create_course();
+        $contextid = context_course::instance($course->id)->id;
+        $grouping = self::getDataGenerator()->create_grouping(['courseid' => $course->id]);
+        $manageroleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/course:managegroups', CAP_ALLOW, $manageroleid, $contextid, true);
+
+        $viewroleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/course:view', CAP_ALLOW, $viewroleid, $contextid, true);
+
+        $viewandmanageroleid = self::getDataGenerator()->create_role();
+        assign_capability('moodle/course:managegroups', CAP_ALLOW, $viewandmanageroleid, $contextid, true);
+        assign_capability('moodle/course:view', CAP_ALLOW, $viewandmanageroleid, $contextid, true);
+
+        $field = $this->create_grouping_custom_field();
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+        $user3 = self::getDataGenerator()->create_user();
+
+        self::setUser($user1);
+        $this->assertFalse($this->handler->can_view($field, $grouping->id));
+
+        self::setUser($user2);
+        $this->assertFalse($this->handler->can_view($field, $grouping->id));
+
+        self::setUser($user3);
+        $this->assertFalse($this->handler->can_view($field, $grouping->id));
+
+        role_assign($manageroleid, $user1->id, $contextid);
+        role_assign($viewroleid, $user2->id, $contextid);
+        role_assign($viewandmanageroleid, $user3->id, $contextid);
+
+        self::setUser($user1);
+        $this->assertTrue($this->handler->can_view($field, $grouping->id));
+
+        self::setUser($user2);
+        $this->assertTrue($this->handler->can_view($field, $grouping->id));
+
+        self::setUser($user3);
+        $this->assertTrue($this->handler->can_view($field, $grouping->id));
+    }
+}

group/tests/fixtures/groups_import.csv

@@ -0,0 +1,6 @@
+groupname, description, groupidnumber,groupingname,enablemessaging
+group-id-1, group-id-1, group-id-1,Grouping-1,1
+group-id-2, group-id-2, group-id-2,Grouping-2,0
+group-id-1-duplicate, Duplicate of group-id-1, group-id-1,Grouping-3,0
+group-noid-1, group-noid-1,,Grouping-3,0
+group-noid-2, group-noid-2,,Grouping-2,0

group/tests/fixtures/groups_import_multicourse.csv

@@ -0,0 +1,6 @@
+coursename,groupname
+C1,group7
+C-non-existing,group-will-not-be-created
+C1,group8
+C2,group9
+,group10

group/tests/fixtures/groups_import_with_customfield.csv

@@ -0,0 +1,3 @@
+groupname, description, groupidnumber, groupingname, customfield_groupfield1, grouping_customfield_groupingfield1
+Group1, Group1-Desc, group-id1, Grouping1, Group1-Custom, Grouping1-Custom
+Group2, Group1-Desc, group-id2, Grouping1, Group2-Custom, Grouping1-Custom

group/tests/lib_test.php

@@ -0,0 +1,971 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Unit tests for group lib.
+ *
+ * @package    core_group
+ * @copyright  2013 Frédéric Massart
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace core_group;
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->dirroot . '/group/lib.php');
+require_once($CFG->dirroot . '/lib/grouplib.php');
+
+/**
+ * Group lib testcase.
+ *
+ * @package    core_group
+ * @copyright  2013 Frédéric Massart
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class lib_test extends \advanced_testcase {
+
+    public function test_member_added_event(): void {
+        $this->resetAfterTest();
+
+        $this->setAdminUser();
+        $course = $this->getDataGenerator()->create_course();
+        $user = $this->getDataGenerator()->create_user();
+        $group = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $this->getDataGenerator()->enrol_user($user->id, $course->id);
+
+        $sink = $this->redirectEvents();
+        groups_add_member($group->id, $user->id, 'mod_workshop', '123');
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+
+        $this->assertInstanceOf('\core\event\group_member_added', $event);
+        $this->assertEquals($user->id, $event->relateduserid);
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($group->id, $event->objectid);
+        $url = new \moodle_url('/group/members.php', array('group' => $event->objectid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_member_removed_event(): void {
+        $this->resetAfterTest();
+
+        $this->setAdminUser();
+        $course = $this->getDataGenerator()->create_course();
+        $user = $this->getDataGenerator()->create_user();
+        $group = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $this->getDataGenerator()->enrol_user($user->id, $course->id);
+        $this->getDataGenerator()->create_group_member(array('userid' => $user->id, 'groupid' => $group->id));
+
+        $sink = $this->redirectEvents();
+        groups_remove_member($group->id, $user->id);
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+
+        $this->assertInstanceOf('\core\event\group_member_removed', $event);
+        $this->assertEquals($user->id, $event->relateduserid);
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($group->id, $event->objectid);
+        $url = new \moodle_url('/group/members.php', array('group' => $event->objectid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_group_created_event(): void {
+        $this->resetAfterTest();
+
+        $this->setAdminUser();
+        $course = $this->getDataGenerator()->create_course();
+
+        $sink = $this->redirectEvents();
+        $group = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+
+        $this->assertInstanceOf('\core\event\group_created', $event);
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($group->id, $event->objectid);
+        $url = new \moodle_url('/group/index.php', array('id' => $event->courseid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_grouping_created_event(): void {
+        $this->resetAfterTest();
+
+        $this->setAdminUser();
+        $course = $this->getDataGenerator()->create_course();
+
+        $sink = $this->redirectEvents();
+        $group = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+
+        $this->assertInstanceOf('\core\event\grouping_created', $event);
+
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($group->id, $event->objectid);
+        $url = new \moodle_url('/group/groupings.php', array('id' => $event->courseid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_group_updated_event(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $group = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+
+        $sink = $this->redirectEvents();
+        $data = new \stdClass();
+        $data->id = $group->id;
+        $data->courseid = $course->id;
+        $data->name = 'Backend team';
+        $this->setCurrentTimeStart();
+        groups_update_group($data);
+        $group = $DB->get_record('groups', array('id'=>$group->id)); // Fetch record with modified timestamp.
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+        $this->assertTimeCurrent($group->timemodified);
+
+        $this->assertInstanceOf('\core\event\group_updated', $event);
+        $group->name = $data->name;
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($group->id, $event->objectid);
+        $url = new \moodle_url('/group/group.php', array('id' => $event->objectid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_group_updated_event_does_not_require_names(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $group = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+
+        $sink = $this->redirectEvents();
+        $data = new \stdClass();
+        $data->id = $group->id;
+        $data->courseid = $course->id;
+        $this->setCurrentTimeStart();
+        groups_update_group($data);
+        $group = $DB->get_record('groups', array('id'=>$group->id)); // Fetch record with modified timestamp.
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+        $this->assertTimeCurrent($group->timemodified);
+
+        $this->assertInstanceOf('\core\event\group_updated', $event);
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($group->id, $event->objectid);
+        $url = new \moodle_url('/group/group.php', array('id' => $event->objectid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_grouping_updated_event(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $grouping = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+
+        $sink = $this->redirectEvents();
+        $data = new \stdClass();
+        $data->id = $grouping->id;
+        $data->courseid = $course->id;
+        $data->name = 'Backend team';
+        $this->setCurrentTimeStart();
+        groups_update_grouping($data);
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+
+        $this->assertInstanceOf('\core\event\grouping_updated', $event);
+
+        // Get the timemodified from DB for comparison with snapshot.
+        $data->timemodified = $DB->get_field('groupings', 'timemodified', array('id'=>$grouping->id));
+        $this->assertTimeCurrent($data->timemodified);
+
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($grouping->id, $event->objectid);
+        $url = new \moodle_url('/group/grouping.php', array('id' => $event->objectid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_grouping_updated_event_does_not_require_names(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $grouping = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+
+        $sink = $this->redirectEvents();
+        $data = new \stdClass();
+        $data->id = $grouping->id;
+        $data->courseid = $course->id;
+        $this->setCurrentTimeStart();
+        groups_update_grouping($data);
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+
+        $this->assertInstanceOf('\core\event\grouping_updated', $event);
+
+        // Get the timemodified from DB for comparison with snapshot.
+        $data->timemodified = $DB->get_field('groupings', 'timemodified', array('id'=>$grouping->id));
+        $this->assertTimeCurrent($data->timemodified);
+        // Following fields were not updated so the snapshot should have them the same as in original group.
+        $data->description = $grouping->description;
+        $data->descriptionformat = $grouping->descriptionformat;
+        $data->configdata = $grouping->configdata;
+        $data->idnumber = $grouping->idnumber;
+        $data->name = $grouping->name;
+        $data->timecreated = $grouping->timecreated;
+
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($grouping->id, $event->objectid);
+        $url = new \moodle_url('/group/grouping.php', array('id' => $event->objectid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_group_deleted_event(): void {
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $group = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+
+        $sink = $this->redirectEvents();
+        groups_delete_group($group->id);
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($group->id, $event->objectid);
+        $url = new \moodle_url('/group/index.php', array('id' => $event->courseid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_grouping_deleted_event(): void {
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $group = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+
+        $sink = $this->redirectEvents();
+        groups_delete_grouping($group->id);
+        $events = $sink->get_events();
+        $this->assertCount(1, $events);
+        $event = reset($events);
+
+        $this->assertInstanceOf('\core\event\grouping_deleted', $event);
+        $this->assertEquals(\context_course::instance($course->id), $event->get_context());
+        $this->assertEquals($group->id, $event->objectid);
+        $url = new \moodle_url('/group/groupings.php', array('id' => $event->courseid));
+        $this->assertEquals($url, $event->get_url());
+    }
+
+    public function test_groups_delete_group_members(): void {
+        global $DB;
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $user1 = $this->getDataGenerator()->create_user();
+        $user2 = $this->getDataGenerator()->create_user();
+        $this->getDataGenerator()->enrol_user($user1->id, $course->id);
+        $this->getDataGenerator()->enrol_user($user2->id, $course->id);
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $group2 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+
+        // Test deletion of all the users.
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group2->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user2->id));
+
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group2->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user2->id)));
+        groups_delete_group_members($course->id);
+        $this->assertFalse($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user1->id)));
+        $this->assertFalse($DB->record_exists('groups_members', array('groupid' => $group2->id, 'userid' => $user1->id)));
+        $this->assertFalse($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user2->id)));
+
+        // Test deletion of a specific user.
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group2->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user2->id));
+
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group2->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user2->id)));
+        groups_delete_group_members($course->id, $user2->id);
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group2->id, 'userid' => $user1->id)));
+        $this->assertFalse($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user2->id)));
+    }
+
+    public function test_groups_remove_member(): void {
+        global $DB;
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $user1 = $this->getDataGenerator()->create_user();
+        $user2 = $this->getDataGenerator()->create_user();
+        $this->getDataGenerator()->enrol_user($user1->id, $course->id);
+        $this->getDataGenerator()->enrol_user($user2->id, $course->id);
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $group2 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group2->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user2->id));
+
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group2->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user2->id)));
+        groups_remove_member($group1->id, $user1->id);
+        $this->assertFalse($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group2->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user2->id)));
+        groups_remove_member($group1->id, $user2->id);
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group2->id, 'userid' => $user1->id)));
+        $this->assertFalse($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user2->id)));
+        groups_remove_member($group2->id, $user1->id);
+        $this->assertFalse($DB->record_exists('groups_members', array('groupid' => $group2->id, 'userid' => $user1->id)));
+    }
+
+    public function test_groups_delete_groupings_groups(): void {
+        global $DB;
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $course2 = $this->getDataGenerator()->create_course();
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $group2 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $group1c2 = $this->getDataGenerator()->create_group(array('courseid' => $course2->id));
+        $grouping1 = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+        $grouping2 = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+        $grouping1c2 = $this->getDataGenerator()->create_grouping(array('courseid' => $course2->id));
+
+        $this->getDataGenerator()->create_grouping_group(array('groupingid' => $grouping1->id, 'groupid' => $group1->id));
+        $this->getDataGenerator()->create_grouping_group(array('groupingid' => $grouping1->id, 'groupid' => $group2->id));
+        $this->getDataGenerator()->create_grouping_group(array('groupingid' => $grouping2->id, 'groupid' => $group1->id));
+        $this->getDataGenerator()->create_grouping_group(array('groupingid' => $grouping1c2->id, 'groupid' => $group1c2->id));
+        $this->assertTrue($DB->record_exists('groupings_groups', array('groupid' => $group1->id, 'groupingid' => $grouping1->id)));
+        $this->assertTrue($DB->record_exists('groupings_groups', array('groupid' => $group2->id, 'groupingid' => $grouping1->id)));
+        $this->assertTrue($DB->record_exists('groupings_groups', array('groupid' => $group1->id, 'groupingid' => $grouping2->id)));
+        $this->assertTrue($DB->record_exists('groupings_groups',
+            array('groupid' => $group1c2->id, 'groupingid' => $grouping1c2->id)));
+        groups_delete_groupings_groups($course->id);
+        $this->assertFalse($DB->record_exists('groupings_groups', array('groupid' => $group1->id, 'groupingid' => $grouping1->id)));
+        $this->assertFalse($DB->record_exists('groupings_groups', array('groupid' => $group2->id, 'groupingid' => $grouping1->id)));
+        $this->assertFalse($DB->record_exists('groupings_groups', array('groupid' => $group1->id, 'groupingid' => $grouping2->id)));
+        $this->assertTrue($DB->record_exists('groupings_groups',
+            array('groupid' => $group1c2->id, 'groupingid' => $grouping1c2->id)));
+    }
+
+    public function test_groups_delete_groups(): void {
+        global $DB;
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $course2 = $this->getDataGenerator()->create_course();
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $group2 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $group1c2 = $this->getDataGenerator()->create_group(array('courseid' => $course2->id));
+        $grouping1 = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+        $grouping2 = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+        $user1 = $this->getDataGenerator()->create_user();
+        $this->getDataGenerator()->enrol_user($user1->id, $course->id);
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_grouping_group(array('groupid' => $group1->id, 'groupingid' => $grouping1->id));
+
+        $this->assertTrue($DB->record_exists('groups', array('id' => $group1->id, 'courseid' => $course->id)));
+        $this->assertTrue($DB->record_exists('groups', array('id' => $group2->id, 'courseid' => $course->id)));
+        $this->assertTrue($DB->record_exists('groups', array('id' => $group1c2->id, 'courseid' => $course2->id)));
+        $this->assertTrue($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groupings', array('id' => $grouping1->id, 'courseid' => $course->id)));
+        $this->assertTrue($DB->record_exists('groupings_groups', array('groupid' => $group1->id, 'groupingid' => $grouping1->id)));
+        groups_delete_groups($course->id);
+        $this->assertFalse($DB->record_exists('groups', array('id' => $group1->id, 'courseid' => $course->id)));
+        $this->assertFalse($DB->record_exists('groups', array('id' => $group2->id, 'courseid' => $course->id)));
+        $this->assertTrue($DB->record_exists('groups', array('id' => $group1c2->id, 'courseid' => $course2->id)));
+        $this->assertFalse($DB->record_exists('groups_members', array('groupid' => $group1->id, 'userid' => $user1->id)));
+        $this->assertTrue($DB->record_exists('groupings', array('id' => $grouping1->id, 'courseid' => $course->id)));
+        $this->assertFalse($DB->record_exists('groupings_groups', array('groupid' => $group1->id, 'groupingid' => $grouping1->id)));
+    }
+
+    public function test_groups_delete_groupings(): void {
+        global $DB;
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $course2 = $this->getDataGenerator()->create_course();
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $grouping1 = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+        $grouping2 = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+        $grouping1c2 = $this->getDataGenerator()->create_grouping(array('courseid' => $course2->id));
+        $this->getDataGenerator()->create_grouping_group(array('groupid' => $group1->id, 'groupingid' => $grouping1->id));
+
+        $this->assertTrue($DB->record_exists('groups', array('id' => $group1->id, 'courseid' => $course->id)));
+        $this->assertTrue($DB->record_exists('groupings', array('id' => $grouping1->id, 'courseid' => $course->id)));
+        $this->assertTrue($DB->record_exists('groupings', array('id' => $grouping2->id, 'courseid' => $course->id)));
+        $this->assertTrue($DB->record_exists('groupings', array('id' => $grouping1c2->id, 'courseid' => $course2->id)));
+        $this->assertTrue($DB->record_exists('groupings_groups', array('groupid' => $group1->id, 'groupingid' => $grouping1->id)));
+        groups_delete_groupings($course->id);
+        $this->assertTrue($DB->record_exists('groups', array('id' => $group1->id, 'courseid' => $course->id)));
+        $this->assertFalse($DB->record_exists('groupings', array('id' => $grouping1->id, 'courseid' => $course->id)));
+        $this->assertFalse($DB->record_exists('groupings', array('id' => $grouping2->id, 'courseid' => $course->id)));
+        $this->assertTrue($DB->record_exists('groupings', array('id' => $grouping1c2->id, 'courseid' => $course2->id)));
+        $this->assertFalse($DB->record_exists('groupings_groups', array('groupid' => $group1->id, 'groupingid' => $grouping1->id)));
+    }
+
+    /**
+     * Test custom field for group.
+     * @covers ::groups_create_group
+     * @covers ::groups_get_group
+     */
+    public function test_groups_with_customfield(): void {
+        $this->resetAfterTest();
+        $this->setAdminUser();
+
+        $course1 = self::getDataGenerator()->create_course();
+        $course2 = self::getDataGenerator()->create_course();
+
+        $groupfieldcategory = self::getDataGenerator()->create_custom_field_category([
+            'component' => 'core_group',
+            'area' => 'group',
+        ]);
+        $groupcustomfield = self::getDataGenerator()->create_custom_field([
+            'shortname' => 'testgroupcustomfield1',
+            'type' => 'text',
+            'categoryid' => $groupfieldcategory->get('id'),
+        ]);
+        $groupingfieldcategory = self::getDataGenerator()->create_custom_field_category([
+            'component' => 'core_group',
+            'area' => 'grouping',
+        ]);
+        $groupingcustomfield = self::getDataGenerator()->create_custom_field([
+            'shortname' => 'testgroupingcustomfield1',
+            'type' => 'text',
+            'categoryid' => $groupingfieldcategory->get('id'),
+        ]);
+
+        $group1 = self::getDataGenerator()->create_group([
+            'courseid' => $course1->id,
+            'customfield_testgroupcustomfield1' => 'Custom input for group1',
+        ]);
+        $group2 = self::getDataGenerator()->create_group([
+            'courseid' => $course2->id,
+            'customfield_testgroupcustomfield1' => 'Custom input for group2',
+        ]);
+        $grouping1 = self::getDataGenerator()->create_grouping([
+            'courseid' => $course1->id,
+            'customfield_testgroupingcustomfield1' => 'Custom input for grouping1',
+        ]);
+        $grouping2 = self::getDataGenerator()->create_grouping([
+            'courseid' => $course2->id,
+            'customfield_testgroupingcustomfield1' => 'Custom input for grouping2',
+        ]);
+
+        $grouphandler = \core_group\customfield\group_handler::create();
+        $data = $grouphandler->export_instance_data_object($group1->id);
+        $this->assertSame('Custom input for group1', $data->testgroupcustomfield1);
+        $data = $grouphandler->export_instance_data_object($group2->id);
+        $this->assertSame('Custom input for group2', $data->testgroupcustomfield1);
+
+        $groupinghandler = \core_group\customfield\grouping_handler::create();
+        $data = $groupinghandler->export_instance_data_object($grouping1->id);
+        $this->assertSame('Custom input for grouping1', $data->testgroupingcustomfield1);
+        $data = $groupinghandler->export_instance_data_object($grouping2->id);
+        $this->assertSame('Custom input for grouping2', $data->testgroupingcustomfield1);
+
+        $group1->customfield_testgroupcustomfield1 = 'Updated input for group1';
+        $group2->customfield_testgroupcustomfield1 = 'Updated input for group2';
+        groups_update_group($group1);
+        groups_update_group($group2);
+        $data = $grouphandler->export_instance_data_object($group1->id);
+        $this->assertSame('Updated input for group1', $data->testgroupcustomfield1);
+        $data = $grouphandler->export_instance_data_object($group2->id);
+        $this->assertSame('Updated input for group2', $data->testgroupcustomfield1);
+
+        $group = groups_get_group($group1->id, '*', IGNORE_MISSING, true);
+        $this->assertCount(1, $group->customfields);
+        $customfield = reset($group->customfields);
+        $this->assertSame('Updated input for group1', $customfield['value']);
+
+        $grouping1->customfield_testgroupingcustomfield1 = 'Updated input for grouping1';
+        $grouping2->customfield_testgroupingcustomfield1 = 'Updated input for grouping2';
+        groups_update_grouping($grouping1);
+        groups_update_grouping($grouping2);
+        $data = $groupinghandler->export_instance_data_object($grouping1->id);
+        $this->assertSame('Updated input for grouping1', $data->testgroupingcustomfield1);
+        $data = $groupinghandler->export_instance_data_object($grouping2->id);
+        $this->assertSame('Updated input for grouping2', $data->testgroupingcustomfield1);
+
+        $grouping = groups_get_grouping($grouping1->id, '*', IGNORE_MISSING, true);
+        $this->assertCount(1, $grouping->customfields);
+        $customfield = reset($grouping->customfields);
+        $this->assertSame('Updated input for grouping1', $customfield['value']);
+    }
+
+    public function test_groups_create_autogroups(): void {
+        global $DB;
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $group2 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $group3 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        $grouping1 = $this->getDataGenerator()->create_grouping(array('courseid' => $course->id));
+        $this->getDataGenerator()->create_grouping_group(array('groupid' => $group2->id, 'groupingid' => $grouping1->id));
+        $this->getDataGenerator()->create_grouping_group(array('groupid' => $group3->id, 'groupingid' => $grouping1->id));
+        $user1 = $this->getDataGenerator()->create_user();
+        $user2 = $this->getDataGenerator()->create_user();
+        $user3 = $this->getDataGenerator()->create_user();
+        $user4 = $this->getDataGenerator()->create_user();
+        $this->getDataGenerator()->enrol_user($user1->id, $course->id);
+        $this->getDataGenerator()->enrol_user($user2->id, $course->id);
+        $this->getDataGenerator()->enrol_user($user3->id, $course->id);
+        $this->getDataGenerator()->enrol_user($user4->id, $course->id);
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user2->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group2->id, 'userid' => $user3->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group3->id, 'userid' => $user4->id));
+
+        // Test autocreate group based on all course users.
+        $users = groups_get_potential_members($course->id);
+        $group4 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        foreach ($users as $user) {
+            $this->getDataGenerator()->create_group_member(array('groupid' => $group4->id, 'userid' => $user->id));
+        }
+        $this->assertEquals(4, $DB->count_records('groups_members', array('groupid' => $group4->id)));
+
+        // Test autocreate group based on existing group.
+        $source = array();
+        $source['groupid'] = $group1->id;
+        $users = groups_get_potential_members($course->id, 0, $source);
+        $group5 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        foreach ($users as $user) {
+            $this->getDataGenerator()->create_group_member(array('groupid' => $group5->id, 'userid' => $user->id));
+        }
+        $this->assertEquals(2, $DB->count_records('groups_members', array('groupid' => $group5->id)));
+
+        // Test autocreate group based on existing grouping.
+        $source = array();
+        $source['groupingid'] = $grouping1->id;
+        $users = groups_get_potential_members($course->id, 0, $source);
+        $group6 = $this->getDataGenerator()->create_group(array('courseid' => $course->id));
+        foreach ($users as $user) {
+            $this->getDataGenerator()->create_group_member(array('groupid' => $group6->id, 'userid' => $user->id));
+        }
+        $this->assertEquals(2, $DB->count_records('groups_members', array('groupid' => $group6->id)));
+    }
+
+    /**
+     * Test groups_create_group enabling a group conversation.
+     */
+    public function test_groups_create_group_with_conversation(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+        $this->setAdminUser();
+        $course1 = $this->getDataGenerator()->create_course();
+        $coursecontext1 = \context_course::instance($course1->id);
+
+        // Create two groups and only one group with enablemessaging = 1.
+        $group1a = $this->getDataGenerator()->create_group(array('courseid' => $course1->id, 'enablemessaging' => 1));
+        $group1b = $this->getDataGenerator()->create_group(array('courseid' => $course1->id, 'enablemessaging' => 0));
+
+        $conversations = $DB->get_records('message_conversations',
+            [
+                'contextid' => $coursecontext1->id,
+                'component' => 'core_group',
+                'itemtype' => 'groups',
+                'enabled' => \core_message\api::MESSAGE_CONVERSATION_ENABLED
+            ]
+        );
+        $this->assertCount(1, $conversations);
+
+        $conversation = reset($conversations);
+        // Check groupid was stored in itemid on conversation area.
+        $this->assertEquals($group1a->id, $conversation->itemid);
+
+        $conversations = $DB->get_records('message_conversations', ['id' => $conversation->id]);
+        $this->assertCount(1, $conversations);
+
+        $conversation = reset($conversations);
+
+        // Check group name was stored in conversation.
+        $this->assertEquals($group1a->name, $conversation->name);
+    }
+
+    /**
+     * Test groups_update_group enabling and disabling a group conversation.
+     */
+    public function test_groups_update_group_conversation(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+        $this->setAdminUser();
+        $course1 = $this->getDataGenerator()->create_course();
+        $coursecontext1 = \context_course::instance($course1->id);
+
+        // Create two groups and only one group with enablemessaging = 1.
+        $group1a = $this->getDataGenerator()->create_group(array('courseid' => $course1->id, 'enablemessaging' => 1));
+        $group1b = $this->getDataGenerator()->create_group(array('courseid' => $course1->id, 'enablemessaging' => 0));
+
+        $conversations = $DB->get_records('message_conversations',
+            [
+                'contextid' => $coursecontext1->id,
+                'component' => 'core_group',
+                'itemtype' => 'groups',
+                'enabled' => \core_message\api::MESSAGE_CONVERSATION_ENABLED
+            ]
+        );
+        $this->assertCount(1, $conversations);
+
+        // Check that the conversation area is created when group messaging is enabled in the course group.
+        $group1b->enablemessaging = 1;
+        groups_update_group($group1b);
+
+        $conversations = $DB->get_records('message_conversations',
+            [
+                'contextid' => $coursecontext1->id,
+                'component' => 'core_group',
+                'itemtype' => 'groups',
+                'enabled' => \core_message\api::MESSAGE_CONVERSATION_ENABLED
+            ],
+        'id ASC');
+        $this->assertCount(2, $conversations);
+
+        $conversation1a = array_shift($conversations);
+        $conversation1b = array_shift($conversations);
+
+        $conversation1b = $DB->get_record('message_conversations', ['id' => $conversation1b->id]);
+
+        // Check for group1b that group name was stored in conversation.
+        $this->assertEquals($group1b->name, $conversation1b->name);
+
+        $group1b->enablemessaging = 0;
+        groups_update_group($group1b);
+        $this->assertEquals(0, $DB->get_field("message_conversations", "enabled", ['id' => $conversation1b->id]));
+
+        // Check that the name of the conversation is changed when the name of the course group is updated.
+        $group1b->name = 'New group name';
+        groups_update_group($group1b);
+        $conversation1b = $DB->get_record('message_conversations', ['id' => $conversation1b->id]);
+        $this->assertEquals($group1b->name, $conversation1b->name);
+    }
+
+    /**
+     * Test groups_add_member to conversation.
+     */
+    public function test_groups_add_member_conversation(): void {
+        global $DB;
+        $this->resetAfterTest();
+
+        $this->setAdminUser();
+
+        $course1 = $this->getDataGenerator()->create_course();
+        $coursecontext1 = \context_course::instance($course1->id);
+
+        $user1 = $this->getDataGenerator()->create_user();
+        $user2 = $this->getDataGenerator()->create_user();
+        $user3 = $this->getDataGenerator()->create_user();
+
+        $this->getDataGenerator()->enrol_user($user1->id, $course1->id);
+        $this->getDataGenerator()->enrol_user($user2->id, $course1->id);
+        $this->getDataGenerator()->enrol_user($user3->id, $course1->id);
+
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course1->id, 'enablemessaging' => 1));
+
+        // Add users to group1.
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user2->id));
+
+        $conversation = \core_message\api::get_conversation_by_area(
+            'core_group',
+            'groups',
+            $group1->id,
+            $coursecontext1->id
+        );
+
+        // Check if the users has been added to the conversation.
+        $this->assertEquals(2, $DB->count_records('message_conversation_members', ['conversationid' => $conversation->id]));
+
+        // Check if the user has been added to the conversation when the conversation is disabled.
+        \core_message\api::disable_conversation($conversation->id);
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user3->id));
+        $this->assertEquals(3, $DB->count_records('message_conversation_members', ['conversationid' => $conversation->id]));
+    }
+
+    /**
+     * Test groups_remove_member to conversation.
+     */
+    public function test_groups_remove_member_conversation(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        $this->setAdminUser();
+
+        $course1 = $this->getDataGenerator()->create_course();
+        $coursecontext1 = \context_course::instance($course1->id);
+
+        $user1 = $this->getDataGenerator()->create_user();
+        $user2 = $this->getDataGenerator()->create_user();
+        $user3 = $this->getDataGenerator()->create_user();
+
+        $this->getDataGenerator()->enrol_user($user1->id, $course1->id);
+        $this->getDataGenerator()->enrol_user($user2->id, $course1->id);
+        $this->getDataGenerator()->enrol_user($user3->id, $course1->id);
+
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course1->id, 'enablemessaging' => 1));
+
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user2->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user3->id));
+
+        $conversation = \core_message\api::get_conversation_by_area(
+            'core_group',
+            'groups',
+            $group1->id,
+            $coursecontext1->id
+        );
+
+        // Check if there are three users in the conversation.
+        $this->assertEquals(3, $DB->count_records('message_conversation_members', ['conversationid' => $conversation->id]));
+
+        // Check if after removing one member in the conversation there are two members.
+        groups_remove_member($group1->id, $user1->id);
+        $this->assertEquals(2, $DB->count_records('message_conversation_members', ['conversationid' => $conversation->id]));
+
+        // Check if the user has been removed from the conversation when the conversation is disabled.
+        \core_message\api::disable_conversation($conversation->id);
+        groups_remove_member($group1->id, $user2->id);
+        $this->assertEquals(1, $DB->count_records('message_conversation_members', ['conversationid' => $conversation->id]));
+    }
+
+    /**
+     * Test if you enable group messaging in a group with members these are added to the conversation.
+     */
+    public function test_add_members_group_updated_conversation_enabled(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        $this->setAdminUser();
+
+        $course1 = $this->getDataGenerator()->create_course();
+        $coursecontext1 = \context_course::instance($course1->id);
+
+        $user1 = $this->getDataGenerator()->create_user();
+        $user2 = $this->getDataGenerator()->create_user();
+        $user3 = $this->getDataGenerator()->create_user();
+
+        $this->getDataGenerator()->enrol_user($user1->id, $course1->id);
+        $this->getDataGenerator()->enrol_user($user2->id, $course1->id);
+        $this->getDataGenerator()->enrol_user($user3->id, $course1->id);
+
+        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course1->id, 'enablemessaging' => 0));
+
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user1->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user2->id));
+        $this->getDataGenerator()->create_group_member(array('groupid' => $group1->id, 'userid' => $user3->id));
+
+        $conversation = \core_message\api::get_conversation_by_area(
+            'core_group',
+            'groups',
+            $group1->id,
+            $coursecontext1->id
+        );
+
+        // No conversation should exist as 'enablemessaging' was set to 0.
+        $this->assertFalse($conversation);
+
+        // Check that the three users are in the conversation when group messaging is enabled in the course group.
+        $group1->enablemessaging = 1;
+        groups_update_group($group1);
+
+        $conversation = \core_message\api::get_conversation_by_area(
+            'core_group',
+            'groups',
+            $group1->id,
+            $coursecontext1->id
+        );
+
+        $this->assertEquals(3, $DB->count_records('message_conversation_members', ['conversationid' => $conversation->id]));
+    }
+
+    public function test_groups_get_members_by_role(): void {
+        $this->resetAfterTest();
+
+        $this->setAdminUser();
+
+        $course1 = $this->getDataGenerator()->create_course();
+
+        $user1 = $this->getDataGenerator()->create_user(['username' => 'user1', 'idnumber' => 1]);
+        $user2 = $this->getDataGenerator()->create_user(['username' => 'user2', 'idnumber' => 2]);
+        $user3 = $this->getDataGenerator()->create_user(['username' => 'user3', 'idnumber' => 3]);
+
+        $this->getDataGenerator()->enrol_user($user1->id, $course1->id, 0);
+        $this->getDataGenerator()->enrol_user($user2->id, $course1->id, 1);
+        $this->getDataGenerator()->enrol_user($user3->id, $course1->id, 1);
+
+        $group1 = $this->getDataGenerator()->create_group(['courseid' => $course1->id]);
+
+        $this->getDataGenerator()->create_group_member(['groupid' => $group1->id, 'userid' => $user1->id]);
+        $this->getDataGenerator()->create_group_member(['groupid' => $group1->id, 'userid' => $user2->id]);
+        $this->getDataGenerator()->create_group_member(['groupid' => $group1->id, 'userid' => $user3->id]);
+
+        // Test basic usage.
+        $result = groups_get_members_by_role($group1->id, $course1->id);
+        $this->assertEquals(1, count($result[0]->users));
+        $this->assertEquals(2, count($result[1]->users));
+        $this->assertEquals($user1->firstname, reset($result[0]->users)->firstname);
+        $this->assertEquals($user1->username, reset($result[0]->users)->username);
+
+        // Test with specified fields.
+        $result = groups_get_members_by_role($group1->id, $course1->id, 'u.firstname, u.lastname');
+        $this->assertEquals(1, count($result[0]->users));
+        $this->assertEquals($user1->firstname, reset($result[0]->users)->firstname);
+        $this->assertEquals($user1->lastname, reset($result[0]->users)->lastname);
+        $this->assertEquals(false, isset(reset($result[0]->users)->username));
+
+        // Test with sorting.
+        $result = groups_get_members_by_role($group1->id, $course1->id, 'u.username', 'u.username DESC');
+        $this->assertEquals(1, count($result[0]->users));
+        $this->assertEquals($user3->username, reset($result[1]->users)->username);
+        $result = groups_get_members_by_role($group1->id, $course1->id, 'u.username', 'u.username ASC');
+        $this->assertEquals(1, count($result[0]->users));
+        $this->assertEquals($user2->username, reset($result[1]->users)->username);
+
+        // Test with extra WHERE.
+        $result = groups_get_members_by_role(
+            $group1->id,
+            $course1->id,
+            'u.username',
+            null,
+            'u.idnumber > :number',
+            ['number' => 2]);
+        $this->assertEquals(1, count($result));
+        $this->assertEquals(1, count($result[1]->users));
+        $this->assertEquals($user3->username, reset($result[1]->users)->username);
+
+        // Test with join.
+        set_user_preference('reptile', 'snake', $user1);
+        $result = groups_get_members_by_role($group1->id, $course1->id, 'u.username, up.value', null, 'up.name = :prefname',
+                ['prefname' => 'reptile'], 'JOIN {user_preferences} up ON up.userid = u.id');
+        $this->assertEquals('snake', reset($result[0]->users)->value);
+    }
+
+    /**
+     * Tests set_groups_messaging
+     *
+     * @covers \core_group::set_groups_messaging
+     */
+    public function test_set_groups_messaging(): void {
+        $this->resetAfterTest();
+        $this->setAdminUser();
+        $dg = $this->getDataGenerator();
+        $course = $dg->create_course();
+
+        // Create some groups in the course.
+        $groupids = [];
+        for ($i = 0; $i < 5; $i++) {
+            $group = new \stdClass();
+            $group->courseid = $course->id;
+            $group->name = 'group-'.$i;
+            $group->enablemessaging = 0;
+            $groupids[] = groups_create_group($group);
+        }
+
+        // They should all initially be disabled.
+        $alldisabledinitially = $this->check_groups_messaging_status_is($groupids, $course->id, false);
+        $this->assertTrue($alldisabledinitially);
+
+        // Enable messaging for all the groups.
+        set_groups_messaging($groupids, true);
+
+        // Check they were all enabled.
+        $allenabled = $this->check_groups_messaging_status_is($groupids, $course->id, true);
+        $this->assertTrue($allenabled);
+
+        // Disable messaging for all the groups.
+        set_groups_messaging($groupids, false);
+
+        // Check they were all disabled.
+        $alldisabled = $this->check_groups_messaging_status_is($groupids, $course->id, false);
+        $this->assertTrue($alldisabled);
+    }
+
+    /**
+     * Tests set group messaging where it doesn't exist
+     *
+     * @covers \core_group::set_groups_messaging
+     */
+    public function test_set_groups_messaging_doesnt_exist(): void {
+        $this->resetAfterTest();
+        $this->setAdminUser();
+
+        $groupids = [-1];
+
+        $this->expectException('dml_exception');
+        set_groups_messaging($groupids, false);
+    }
+
+    /**
+     * Checks the given list of groups to verify their messaging settings.
+     *
+     * @param array $groupids array of group ids
+     * @param int $courseid the course the groups are in
+     * @param bool $desired the desired setting value
+     * @return bool true if all groups $enablemessaging setting matches the given $desired value, else false
+     */
+    private function check_groups_messaging_status_is(array $groupids, int $courseid, bool $desired) {
+        $context = \context_course::instance($courseid);
+
+        foreach ($groupids as $groupid) {
+            $conversation = \core_message\api::get_conversation_by_area(
+                'core_group',
+                'groups',
+                $groupid,
+                $context->id
+            );
+
+            // An empty conversation means it has not been enabled yet.
+            if (empty($conversation)) {
+                $conversation = (object) [
+                    'enabled' => 0
+                ];
+            }
+
+            if ($desired !== boolval($conversation->enabled)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+}

group/tests/reportbuilder/datasource/groups_test.php

@@ -0,0 +1,406 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+declare(strict_types=1);
+
+namespace core_group\reportbuilder\datasource;
+
+use core_customfield_generator;
+use core_reportbuilder_generator;
+use core_reportbuilder_testcase;
+use core_reportbuilder\local\filters\{boolean_select, date, select, text};
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once("{$CFG->dirroot}/reportbuilder/tests/helpers.php");
+
+/**
+ * Unit tests for groups datasource
+ *
+ * @package     core_group
+ * @covers      \core_group\reportbuilder\datasource\groups
+ * @copyright   2022 Paul Holden <paulh@moodle.com>
+ * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class groups_test extends core_reportbuilder_testcase {
+
+    /**
+     * Test default datasource
+     */
+    public function test_datasource_default(): void {
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+        $userone = $this->getDataGenerator()->create_and_enrol($course, 'student', ['firstname' => 'Zoe']);
+        $usertwo = $this->getDataGenerator()->create_and_enrol($course, 'student', ['firstname' => 'Amy']);
+
+        $groupone = $this->getDataGenerator()->create_group(['courseid' => $course->id, 'name' => 'Zebras']);
+        $grouptwo = $this->getDataGenerator()->create_group(['courseid' => $course->id, 'name' => 'Aardvarks']);
+
+        $this->getDataGenerator()->create_group_member(['groupid' => $groupone->id, 'userid' => $userone->id]);
+        $this->getDataGenerator()->create_group_member(['groupid' => $groupone->id, 'userid' => $usertwo->id]);
+
+        /** @var core_reportbuilder_generator $generator */
+        $generator = $this->getDataGenerator()->get_plugin_generator('core_reportbuilder');
+        $report = $generator->create_report(['name' => 'Groups', 'source' => groups::class, 'default' => 1]);
+
+        $content = $this->get_custom_report_content($report->get('id'));
+
+        // Default columns are course, group, user. Sorted by each.
+        $courseurl = course_get_url($course);
+        $this->assertEquals([
+            ["<a href=\"{$courseurl}\">{$course->fullname}</a>", $grouptwo->name, ''],
+            ["<a href=\"{$courseurl}\">{$course->fullname}</a>", $groupone->name, fullname($usertwo)],
+            ["<a href=\"{$courseurl}\">{$course->fullname}</a>", $groupone->name, fullname($userone)],
+        ], array_map('array_values', $content));
+    }
+
+    /**
+     * Test datasource groupings reports
+     */
+    public function test_datasource_groupings(): void {
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course();
+
+        // Create group, add to grouping.
+        $groupone = $this->getDataGenerator()->create_group(['courseid' => $course->id, 'name' => 'Group A']);
+        $grouping = $this->getDataGenerator()->create_grouping(['courseid' => $course->id]);
+        $this->getDataGenerator()->create_grouping_group(['groupingid' => $grouping->id, 'groupid' => $groupone->id]);
+
+        // Create second group, no grouping.
+        $grouptwo = $this->getDataGenerator()->create_group(['courseid' => $course->id, 'name' => 'Group B']);
+
+        /** @var core_reportbuilder_generator $generator */
+        $generator = $this->getDataGenerator()->get_plugin_generator('core_reportbuilder');
+        $report = $generator->create_report(['name' => 'Groups', 'source' => groups::class, 'default' => 0]);
+
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'course:fullname']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'grouping:name']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:name', 'sortenabled' => 1]);
+
+        $content = $this->get_custom_report_content($report->get('id'));
+        $this->assertCount(2, $content);
+
+        $this->assertEquals([
+            [
+                $course->fullname,
+                $grouping->name,
+                $groupone->name,
+            ],
+            [
+                $course->fullname,
+                null,
+                $grouptwo->name,
+            ],
+        ], array_map('array_values', $content));
+    }
+
+    /**
+     * Test datasource columns that aren't added by default
+     */
+    public function test_datasource_non_default_columns(): void {
+        $this->resetAfterTest();
+        $this->setAdminUser();
+
+        $course = $this->getDataGenerator()->create_course();
+        $user = $this->getDataGenerator()->create_and_enrol($course, 'student');
+
+        /** @var core_customfield_generator $generator */
+        $generator = $this->getDataGenerator()->get_plugin_generator('core_customfield');
+
+        // Create group with custom field, and single group member.
+        $groupfieldcategory = $generator->create_category(['component' => 'core_group', 'area' => 'group']);
+        $generator->create_field(['categoryid' => $groupfieldcategory->get('id'), 'shortname' => 'hi']);
+
+        $group = $this->getDataGenerator()->create_group([
+            'courseid' => $course->id,
+            'idnumber' => 'G101',
+            'enrolmentkey' => 'S',
+            'description' => 'My group',
+            'customfield_hi' => 'Hello',
+        ]);
+        $this->getDataGenerator()->create_group_member(['userid' => $user->id, 'groupid' => $group->id]);
+
+        // Create grouping with custom field, and single group.
+        $groupingfieldcategory = $generator->create_category(['component' => 'core_group', 'area' => 'grouping']);
+        $generator->create_field(['categoryid' => $groupingfieldcategory->get('id'), 'shortname' => 'bye']);
+
+        $grouping = $this->getDataGenerator()->create_grouping([
+            'courseid' => $course->id,
+            'idnumber' => 'GR101',
+            'description' => 'My grouping',
+            'customfield_bye' => 'Goodbye',
+        ]);
+        $this->getDataGenerator()->create_grouping_group(['groupingid' => $grouping->id, 'groupid' => $group->id]);
+
+        /** @var core_reportbuilder_generator $generator */
+        $generator = $this->getDataGenerator()->get_plugin_generator('core_reportbuilder');
+        $report = $generator->create_report(['name' => 'Groups', 'source' => groups::class, 'default' => 0]);
+
+        // Course (just to test join).
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'course:shortname']);
+
+        // Group.
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:idnumber']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:description']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:enrolmentkey']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:visibility']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:participation']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:picture']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:timecreated']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:timemodified']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:customfield_hi']);
+
+        // Grouping.
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'grouping:name']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'grouping:idnumber']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'grouping:description']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'grouping:timecreated']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'grouping:timemodified']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'grouping:customfield_bye']);
+
+        // Group member.
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group_member:timeadded']);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group_member:component']);
+
+        // User (just to test join).
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'user:username']);
+
+        $content = $this->get_custom_report_content($report->get('id'));
+        $this->assertCount(1, $content);
+
+        [
+            $courseshortname,
+            $groupidnumber,
+            $groupdescription,
+            $groupenrolmentkey,
+            $groupvisibility,
+            $groupparticipation,
+            $grouppicture,
+            $grouptimecreated,
+            $grouptimemodified,
+            $groupcustomfield,
+            $groupingname,
+            $groupingidnumber,
+            $groupingdescription,
+            $groupingtimecreated,
+            $groupingtimemodified,
+            $groupingcustomfield,
+            $groupmembertimeadded,
+            $groupmemebercomponent,
+            $userusername,
+        ] = array_values($content[0]);
+
+        $this->assertEquals($course->shortname, $courseshortname);
+        $this->assertEquals('G101', $groupidnumber);
+        $this->assertEquals(format_text($group->description), $groupdescription);
+        $this->assertEquals('S', $groupenrolmentkey);
+        $this->assertEquals('Visible', $groupvisibility);
+        $this->assertEquals('Yes', $groupparticipation);
+        $this->assertEmpty($grouppicture);
+        $this->assertNotEmpty($grouptimecreated);
+        $this->assertNotEmpty($grouptimemodified);
+        $this->assertEquals('Hello', $groupcustomfield);
+        $this->assertEquals($grouping->name, $groupingname);
+        $this->assertEquals('GR101', $groupingidnumber);
+        $this->assertEquals(format_text($grouping->description), $groupingdescription);
+        $this->assertNotEmpty($groupingtimecreated);
+        $this->assertNotEmpty($groupingtimemodified);
+        $this->assertEquals('Goodbye', $groupingcustomfield);
+        $this->assertNotEmpty($groupmembertimeadded);
+        $this->assertEmpty($groupmemebercomponent);
+        $this->assertEquals($user->username, $userusername);
+    }
+
+    /**
+     * Data provider for {@see test_datasource_filters}
+     *
+     * @return array[]
+     */
+    public function datasource_filters_provider(): array {
+        return [
+            // Course (just to test join).
+            'Filter course name' => ['course:fullname', [
+                'course:fullname_operator' => text::IS_EQUAL_TO,
+                'course:fullname_value' => 'Test course',
+            ], true],
+            'Filter course name (no match)' => ['course:fullname', [
+                'course:fullname_operator' => text::IS_NOT_EQUAL_TO,
+                'course:fullname_value' => 'Test course',
+            ], false],
+
+            // Group.
+            'Filter group name' => ['group:name', [
+                'group:name_operator' => text::IS_EQUAL_TO,
+                'group:name_value' => 'Test group',
+            ], true],
+            'Filter group name (no match)' => ['group:name', [
+                'group:name_operator' => text::IS_NOT_EQUAL_TO,
+                'group:name_value' => 'Test group',
+            ], false],
+            'Filter group idnumber' => ['group:idnumber', [
+                'group:idnumber_operator' => text::IS_EQUAL_TO,
+                'group:idnumber_value' => 'G101',
+            ], true],
+            'Filter group idnumber (no match)' => ['group:idnumber', [
+                'group:idnumber_operator' => text::IS_NOT_EQUAL_TO,
+                'group:idnumber_value' => 'G101',
+            ], false],
+            'Filter group visibility' => ['group:visibility', [
+                'group:visibility_operator' => select::EQUAL_TO,
+                'group:visibility_value' => 0, // Visible to everyone.
+            ], true],
+            'Filter group visibility (no match)' => ['group:visibility', [
+                'group:visibility_operator' => select::EQUAL_TO,
+                'group:visibility_value' => 1, // Visible to members only.
+            ], false],
+            'Filter group participation' => ['group:participation', [
+                'group:participation_operator' => boolean_select::CHECKED,
+            ], true],
+            'Filter group participation (no match)' => ['group:participation', [
+                'group:participation_operator' => boolean_select::NOT_CHECKED,
+            ], false],
+            'Filter group time created' => ['group:timecreated', [
+                'group:timecreated_operator' => date::DATE_RANGE,
+                'group:timecreated_from' => 1622502000,
+            ], true],
+            'Filter group time created (no match)' => ['group:timecreated', [
+                'group:timecreated_operator' => date::DATE_RANGE,
+                'group:timecreated_to' => 1622502000,
+            ], false],
+
+            // Grouping.
+            'Filter grouping name' => ['grouping:name', [
+                'grouping:name_operator' => text::IS_EQUAL_TO,
+                'grouping:name_value' => 'Test grouping',
+            ], true],
+            'Filter grouping name (no match)' => ['grouping:name', [
+                'grouping:name_operator' => text::IS_NOT_EQUAL_TO,
+                'grouping:name_value' => 'Test grouping',
+            ], false],
+            'Filter grouping idnumber' => ['grouping:idnumber', [
+                'grouping:idnumber_operator' => text::IS_EQUAL_TO,
+                'grouping:idnumber_value' => 'GR101',
+            ], true],
+            'Filter grouping idnumber (no match)' => ['grouping:idnumber', [
+                'grouping:idnumber_operator' => text::IS_NOT_EQUAL_TO,
+                'grouping:idnumber_value' => 'GR101',
+            ], false],
+            'Filter grouping time created' => ['grouping:timecreated', [
+                'grouping:timecreated_operator' => date::DATE_RANGE,
+                'grouping:timecreated_from' => 1622502000,
+            ], true],
+            'Filter grouping time created (no match)' => ['grouping:timecreated', [
+                'grouping:timecreated_operator' => date::DATE_RANGE,
+                'grouping:timecreated_to' => 1622502000,
+            ], false],
+
+            // Group member.
+            'Filter group member time added' => ['group_member:timeadded', [
+                'group_member:timeadded_operator' => date::DATE_RANGE,
+                'group_member:timeadded_from' => 1622502000,
+            ], true],
+            'Filter group member time added (no match)' => ['group_member:timeadded', [
+                'group_member:timeadded_operator' => date::DATE_RANGE,
+                'group_member:timeadded_to' => 1622502000,
+            ], false],
+
+            // User (just to test join).
+            'Filter user username' => ['user:username', [
+                'user:username_operator' => text::IS_EQUAL_TO,
+                'user:username_value' => 'testuser',
+            ], true],
+            'Filter user username (no match)' => ['user:username', [
+                'user:username_operator' => text::IS_NOT_EQUAL_TO,
+                'user:username_value' => 'testuser',
+            ], false],
+        ];
+    }
+
+    /**
+     * Test datasource filters
+     *
+     * @param string $filtername
+     * @param array $filtervalues
+     * @param bool $expectmatch
+     *
+     * @dataProvider datasource_filters_provider
+     */
+    public function test_datasource_filters(
+        string $filtername,
+        array $filtervalues,
+        bool $expectmatch
+    ): void {
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course(['fullname' => 'Test course']);
+        $user = $this->getDataGenerator()->create_and_enrol($course, 'student', ['username' => 'testuser']);
+
+        $group = $this->getDataGenerator()->create_group(['courseid' => $course->id, 'idnumber' => 'G101', 'name' => 'Test group']);
+        $this->getDataGenerator()->create_group_member(['userid' => $user->id, 'groupid' => $group->id]);
+
+        $grouping = $this->getDataGenerator()->create_grouping(['courseid' => $course->id, 'idnumber' => 'GR101',
+            'name' => 'Test grouping']);
+        $this->getDataGenerator()->create_grouping_group(['groupingid' => $grouping->id, 'groupid' => $group->id]);
+
+        /** @var core_reportbuilder_generator $generator */
+        $generator = $this->getDataGenerator()->get_plugin_generator('core_reportbuilder');
+
+        // Create report containing single column, and given filter.
+        $report = $generator->create_report(['name' => 'Tasks', 'source' => groups::class, 'default' => 0]);
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'group:idnumber']);
+
+        // Add filter, set it's values.
+        $generator->create_filter(['reportid' => $report->get('id'), 'uniqueidentifier' => $filtername]);
+        $content = $this->get_custom_report_content($report->get('id'), 0, $filtervalues);
+
+        if ($expectmatch) {
+            $this->assertCount(1, $content);
+            $this->assertEquals('G101', reset($content[0]));
+        } else {
+            $this->assertEmpty($content);
+        }
+    }
+
+    /**
+     * Stress test datasource
+     *
+     * In order to execute this test PHPUNIT_LONGTEST should be defined as true in phpunit.xml or directly in config.php
+     */
+    public function test_stress_datasource(): void {
+        if (!PHPUNIT_LONGTEST) {
+            $this->markTestSkipped('PHPUNIT_LONGTEST is not defined');
+        }
+
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course(['fullname' => 'Test course']);
+        $user = $this->getDataGenerator()->create_and_enrol($course, 'student', ['username' => 'testuser']);
+
+        $group = $this->getDataGenerator()->create_group(['courseid' => $course->id, 'idnumber' => 'G101', 'name' => 'Test group']);
+        $this->getDataGenerator()->create_group_member(['userid' => $user->id, 'groupid' => $group->id]);
+
+        $grouping = $this->getDataGenerator()->create_grouping(['courseid' => $course->id, 'idnumber' => 'GR101',
+            'name' => 'Test grouping']);
+        $this->getDataGenerator()->create_grouping_group(['groupingid' => $grouping->id, 'groupid' => $group->id]);
+
+        $this->datasource_stress_test_columns(groups::class);
+        $this->datasource_stress_test_columns_aggregation(groups::class);
+        $this->datasource_stress_test_conditions(groups::class, 'group:idnumber');
+    }
+}

group/upgrade.txt

@@ -0,0 +1,44 @@
+This files describes API changes in /group/*,
+information provided here is intended especially for developers.
+
+=== 4.3 ===
+* The following external methods now return group names correctly formatted:
+  - `core_group_get_groups`
+  - `core_group_get_course_groups`
+  - `core_group_get_course_user_groups`
+  - `core_group_get_activity_allowed_groups`
+* Groups now have access to create GeoPattern default images based upon their ID with their associated course context.
+  This can be done by calling the following:
+       moodle_url::make_pluginfile_url(
+           $coursecontext->id,
+           'group',
+           'generated',
+           $group->id,
+           '/',
+           'group.svg'
+       );
+* Added group/grouping custom fields.
+* groups_get_members_join() now includes visibility checks for group memberships.
+* \core_group\visibility::sql_member_visibility_where() no longer prefixes the returned WHERE statement with AND, to
+  give the calling code greater flexibility about how to use it.
+
+=== 4.2 ===
+* `\core_group\visibility` class added to support new `visibility` field in group records. This holds the visibility constants
+  and helper functions for applying visibility restrictions when querying groups or group members in the database.
+* Changes to the group form to support visibility features:
+  - New `visibility` field.
+  - New `participation` field.
+  - `participation` and `enablemessaging` fields are disabled (default: false) when `visibility` is set
+    to `visibility::OWN` or `visibility::NONE`.
+* The following externallib functions now accept `visibility` and `participation` as optional parameters:
+  - create_groups()
+  - update_groups()
+* The following externallib functions now also return `visibility` and `participation` fields in their responses:
+  - create_groups()
+  - get_groups()
+  - get_course_groups()
+
+=== 3.11 ===
+
+* The groups do not support 'hidepicture' any more, and so the column 'hidepicture'
+  from the table {groups} has be dropped.