init source

node_modules/eslint-plugin-import/memo-parser/index.js

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+"use strict"
+
+const crypto = require('crypto')
+    , moduleRequire = require('eslint-module-utils/module-require').default
+    , hashObject = require('eslint-module-utils/hash').hashObject
+
+const cache = new Map()
+
+// must match ESLint default options or we'll miss the cache every time
+const parserOptions = {
+  loc: true,
+  range: true,
+  raw: true,
+  tokens: true,
+  comment: true,
+  attachComment: true,
+}
+
+exports.parse = function parse(content, options) {
+  options = Object.assign({}, options, parserOptions)
+
+  if (!options.filePath) {
+    throw new Error("no file path provided!")
+  }
+
+  const keyHash = crypto.createHash('sha256')
+  keyHash.update(content)
+  hashObject(options, keyHash)
+
+  const key = keyHash.digest('hex')
+
+  let ast = cache.get(key)
+  if (ast != null) return ast
+
+  const realParser = moduleRequire(options.parser)
+
+  ast = realParser.parse(content, options)
+  cache.set(key, ast)
+
+  return ast
+}