* escope finds lexical scopes in a source program, i.e. areas of that * program where different occurrences of the same identifier refer to the same * variable. With each scope the contained variables are collected, and each * identifier reference in code is linked to its corresponding variable (if * possible). *

* escope works on a syntax tree of the parsed source code which has * to adhere to the * Mozilla Parser API. E.g. espree is a parser * that produces such syntax trees. *

* The main interface is the {@link analyze} function. * @module escope */ import { assert } from "./assert.js"; import ScopeManager from "./scope-manager.js"; import Referencer from "./referencer.js"; import Reference from "./reference.js"; import Variable from "./variable.js"; import eslintScopeVersion from "./version.js"; /** * Set the default options * @returns {Object} options */ function defaultOptions() { return { optimistic: false, nodejsScope: false, impliedStrict: false, sourceType: "script", // one of ['script', 'module', 'commonjs'] ecmaVersion: 5, childVisitorKeys: null, fallback: "iteration" }; } /** * Preform deep update on option object * @param {Object} target Options * @param {Object} override Updates * @returns {Object} Updated options */ function updateDeeply(target, override) { /** * Is hash object * @param {Object} value Test value * @returns {boolean} Result */ function isHashObject(value) { return typeof value === "object" && value instanceof Object && !(value instanceof Array) && !(value instanceof RegExp); } for (const key in override) { if (Object.hasOwn(override, key)) { const val = override[key]; if (isHashObject(val)) { if (isHashObject(target[key])) { updateDeeply(target[key], val); } else { target[key] = updateDeeply({}, val); } } else { target[key] = val; } } } return target; } /** * Main interface function. Takes an Espree syntax tree and returns the * analyzed scopes. * @function analyze * @param {espree.Tree} tree Abstract Syntax Tree * @param {Object} providedOptions Options that tailor the scope analysis * @param {boolean} [providedOptions.optimistic=false] the optimistic flag * @param {boolean} [providedOptions.ignoreEval=false] whether to check 'eval()' calls * @param {boolean} [providedOptions.nodejsScope=false] whether the whole * script is executed under node.js environment. When enabled, escope adds * a function scope immediately following the global scope. * @param {boolean} [providedOptions.impliedStrict=false] implied strict mode * (if ecmaVersion >= 5). * @param {string} [providedOptions.sourceType='script'] the source type of the script. one of 'script', 'module', and 'commonjs' * @param {number} [providedOptions.ecmaVersion=5] which ECMAScript version is considered * @param {boolean} [providedOptions.jsx=false] support JSX references * @param {Object} [providedOptions.childVisitorKeys=null] Additional known visitor keys. See [esrecurse](https://github.com/estools/esrecurse)'s the `childVisitorKeys` option. * @param {string} [providedOptions.fallback='iteration'] A kind of the fallback in order to encounter with unknown node. See [esrecurse](https://github.com/estools/esrecurse)'s the `fallback` option. * @returns {ScopeManager} ScopeManager */ function analyze(tree, providedOptions) { const options = updateDeeply(defaultOptions(), providedOptions); const scopeManager = new ScopeManager(options); const referencer = new Referencer(options, scopeManager); referencer.visit(tree); assert(scopeManager.__currentScope === null, "currentScope should be null."); return scopeManager; } export { /** @name module:escope.version */ eslintScopeVersion as version, /** @name module:escope.Reference */ Reference, /** @name module:escope.Variable */ Variable, /** @name module:escope.ScopeManager */ ScopeManager, /** @name module:escope.Referencer */ Referencer, analyze }; /** @name module:escope.Definition */ export { Definition } from "./definition.js"; /** @name module:escope.PatternVisitor */ export { default as PatternVisitor } from "./pattern-visitor.js"; /** @name module:escope.Scope */ export { Scope } from "./scope.js"; /* vim: set sw=4 ts=4 et tw=80 : */