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Diffstat (limited to 'tools/lint/eslint/eslint-plugin-mozilla/lib/globals.js')
-rw-r--r-- | tools/lint/eslint/eslint-plugin-mozilla/lib/globals.js | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/tools/lint/eslint/eslint-plugin-mozilla/lib/globals.js b/tools/lint/eslint/eslint-plugin-mozilla/lib/globals.js new file mode 100644 index 000000000..acbfa0684 --- /dev/null +++ b/tools/lint/eslint/eslint-plugin-mozilla/lib/globals.js @@ -0,0 +1,188 @@ +/** + * @fileoverview functions for scanning an AST for globals including + * traversing referenced scripts. + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + */ + +"use strict"; + +const path = require("path"); +const fs = require("fs"); +const helpers = require("./helpers"); +const escope = require("escope"); +const estraverse = require("estraverse"); + +/** + * Parses a list of "name:boolean_value" or/and "name" options divided by comma or + * whitespace. + * + * This function was copied from eslint.js + * + * @param {string} string The string to parse. + * @param {Comment} comment The comment node which has the string. + * @returns {Object} Result map object of names and boolean values + */ +function parseBooleanConfig(string, comment) { + let items = {}; + + // Collapse whitespace around : to make parsing easier + string = string.replace(/\s*:\s*/g, ":"); + // Collapse whitespace around , + string = string.replace(/\s*,\s*/g, ","); + + string.split(/\s|,+/).forEach(function(name) { + if (!name) { + return; + } + + let pos = name.indexOf(":"); + let value = undefined; + if (pos !== -1) { + value = name.substring(pos + 1, name.length); + name = name.substring(0, pos); + } + + items[name] = { + value: (value === "true"), + comment: comment + }; + }); + + return items; +} + +/** + * Global discovery can require parsing many files. This map of + * {String} => {Object} caches what globals were discovered for a file path. + */ +const globalCache = new Map(); + +/** + * An object that returns found globals for given AST node types. Each prototype + * property should be named for a node type and accepts a node parameter and a + * parents parameter which is a list of the parent nodes of the current node. + * Each returns an array of globals found. + * + * @param {String} path + * The absolute path of the file being parsed. + */ +function GlobalsForNode(path) { + this.path = path; + this.root = helpers.getRootDir(path); +} + +GlobalsForNode.prototype = { + BlockComment(node, parents) { + let value = node.value.trim(); + let match = /^import-globals-from\s+(.+)$/.exec(value); + if (!match) { + return []; + } + + let filePath = match[1].trim(); + + if (!path.isAbsolute(filePath)) { + let dirName = path.dirname(this.path); + filePath = path.resolve(dirName, filePath); + } + + return module.exports.getGlobalsForFile(filePath); + }, + + ExpressionStatement(node, parents) { + let isGlobal = helpers.getIsGlobalScope(parents); + let names = helpers.convertExpressionToGlobals(node, isGlobal, this.root); + return names.map(name => { return { name, writable: true }}); + }, +}; + +module.exports = { + /** + * Returns all globals for a given file. Recursively searches through + * import-globals-from directives and also includes globals defined by + * standard eslint directives. + * + * @param {String} path + * The absolute path of the file to be parsed. + */ + getGlobalsForFile(path) { + if (globalCache.has(path)) { + return globalCache.get(path); + } + + let content = fs.readFileSync(path, "utf8"); + + // Parse the content into an AST + let ast = helpers.getAST(content); + + // Discover global declarations + let scopeManager = escope.analyze(ast); + let globalScope = scopeManager.acquire(ast); + + let globals = Object.keys(globalScope.variables).map(v => ({ + name: globalScope.variables[v].name, + writable: true, + })); + + // Walk over the AST to find any of our custom globals + let handler = new GlobalsForNode(path); + + helpers.walkAST(ast, (type, node, parents) => { + // We have to discover any globals that ESLint would have defined through + // comment directives + if (type == "BlockComment") { + let value = node.value.trim(); + let match = /^globals?\s+(.+)$/.exec(value); + if (match) { + let values = parseBooleanConfig(match[1].trim(), node); + for (let name of Object.keys(values)) { + globals.push({ + name, + writable: values[name].value + }) + } + } + } + + if (type in handler) { + let newGlobals = handler[type](node, parents); + globals.push.apply(globals, newGlobals); + } + }); + + globalCache.set(path, globals); + + return globals; + }, + + /** + * Intended to be used as-is for an ESLint rule that parses for globals in + * the current file and recurses through import-globals-from directives. + * + * @param {Object} context + * The ESLint parsing context. + */ + getESLintGlobalParser(context) { + let globalScope; + + let parser = { + Program(node) { + globalScope = context.getScope(); + } + }; + + // Install thin wrappers around GlobalsForNode + let handler = new GlobalsForNode(helpers.getAbsoluteFilePath(context)); + + for (let type of Object.keys(GlobalsForNode.prototype)) { + parser[type] = function(node) { + let globals = handler[type](node, context.getAncestors()); + helpers.addGlobals(globals, globalScope); + } + } + + return parser; + } +}; |