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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 | 665 |
1 files changed, 665 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 0000000000..aa3d4258ae --- /dev/null +++ b/tools/lint/eslint/eslint-plugin-mozilla/lib/globals.js @@ -0,0 +1,665 @@ +/** + * @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 htmlparser = require("htmlparser2"); + +const callExpressionDefinitions = [ + /^loader\.lazyGetter\((?:globalThis|this), "(\w+)"/, + /^loader\.lazyServiceGetter\((?:globalThis|this), "(\w+)"/, + /^loader\.lazyRequireGetter\((?:globalThis|this), "(\w+)"/, + /^XPCOMUtils\.defineLazyGetter\((?:globalThis|this), "(\w+)"/, + /^XPCOMUtils\.defineLazyModuleGetter\((?:globalThis|this), "(\w+)"/, + /^ChromeUtils\.defineLazyGetter\((?:globalThis|this), "(\w+)"/, + /^ChromeUtils\.defineModuleGetter\((?:globalThis|this), "(\w+)"/, + /^XPCOMUtils\.defineLazyPreferenceGetter\((?:globalThis|this), "(\w+)"/, + /^XPCOMUtils\.defineLazyProxy\((?:globalThis|this), "(\w+)"/, + /^XPCOMUtils\.defineLazyScriptGetter\((?:globalThis|this), "(\w+)"/, + /^XPCOMUtils\.defineLazyServiceGetter\((?:globalThis|this), "(\w+)"/, + /^XPCOMUtils\.defineConstant\((?:globalThis|this), "(\w+)"/, + /^DevToolsUtils\.defineLazyModuleGetter\((?:globalThis|this), "(\w+)"/, + /^DevToolsUtils\.defineLazyGetter\((?:globalThis|this), "(\w+)"/, + /^Object\.defineProperty\((?:globalThis|this), "(\w+)"/, + /^Reflect\.defineProperty\((?:globalThis|this), "(\w+)"/, + /^this\.__defineGetter__\("(\w+)"/, +]; + +const callExpressionMultiDefinitions = [ + "XPCOMUtils.defineLazyGlobalGetters(this,", + "XPCOMUtils.defineLazyGlobalGetters(globalThis,", + "XPCOMUtils.defineLazyModuleGetters(this,", + "XPCOMUtils.defineLazyModuleGetters(globalThis,", + "XPCOMUtils.defineLazyServiceGetters(this,", + "XPCOMUtils.defineLazyServiceGetters(globalThis,", + "ChromeUtils.defineESModuleGetters(this,", + "ChromeUtils.defineESModuleGetters(globalThis,", + "loader.lazyRequireGetter(this,", + "loader.lazyRequireGetter(globalThis,", +]; + +const subScriptMatches = [ + /Services\.scriptloader\.loadSubScript\("(.*?)", this\)/, +]; + +const workerImportFilenameMatch = /(.*\/)*((.*?)\.jsm?)/; + +/** + * 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; + if (pos !== -1) { + value = name.substring(pos + 1, name.length); + name = name.substring(0, pos); + } + + items[name] = { + value: value === "true", + 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(); + +/** + * Global discovery can occasionally meet circular dependencies due to the way + * js files are included via html/xhtml files etc. This set is used to avoid + * getting into loops whilst the discovery is in progress. + */ +var globalDiscoveryInProgressForFiles = new Set(); + +/** + * When looking for globals in HTML files, it can be common to have more than + * one script tag with inline javascript. These will normally be called together, + * so we store the globals for just the last HTML file processed. + */ +var lastHTMLGlobals = {}; + +/** + * Attempts to convert an CallExpressions that look like module imports + * into global variable definitions. + * + * @param {Object} node + * The AST node to convert. + * @param {boolean} isGlobal + * True if the current node is in the global scope. + * + * @return {Array} + * An array of objects that contain details about the globals: + * - {String} name + * The name of the global. + * - {Boolean} writable + * If the global is writeable or not. + */ +function convertCallExpressionToGlobals(node, isGlobal) { + let express = node.expression; + if ( + express.type === "CallExpression" && + express.callee.type === "MemberExpression" && + express.callee.object && + express.callee.object.type === "Identifier" && + express.arguments.length === 1 && + express.arguments[0].type === "ArrayExpression" && + express.callee.property.type === "Identifier" && + express.callee.property.name === "importGlobalProperties" + ) { + return express.arguments[0].elements.map(literal => { + return { + explicit: true, + name: literal.value, + writable: false, + }; + }); + } + + let source; + try { + source = helpers.getASTSource(node); + } catch (e) { + return []; + } + + // The definition matches below must be in the global scope for us to define + // a global, so bail out early if we're not a global. + if (!isGlobal) { + return []; + } + + for (let reg of subScriptMatches) { + let match = source.match(reg); + if (match) { + return getGlobalsForScript(match[1], "script").map(g => { + // We don't want any loadSubScript globals to be explicit, as this + // could trigger no-unused-vars when importing multiple variables + // from a script and not using all of them. + g.explicit = false; + return g; + }); + } + } + + for (let reg of callExpressionDefinitions) { + let match = source.match(reg); + if (match) { + return [{ name: match[1], writable: true, explicit: true }]; + } + } + + if ( + callExpressionMultiDefinitions.some(expr => source.startsWith(expr)) && + node.expression.arguments[1] + ) { + let arg = node.expression.arguments[1]; + if (arg.type === "ObjectExpression") { + return arg.properties + .map(p => ({ + name: p.type === "Property" && p.key.name, + writable: true, + explicit: true, + })) + .filter(g => g.name); + } + if (arg.type === "ArrayExpression") { + return arg.elements + .map(p => ({ + name: p.type === "Literal" && p.value, + writable: true, + explicit: true, + })) + .filter(g => typeof g.name == "string"); + } + } + + if ( + node.expression.callee.type == "MemberExpression" && + node.expression.callee.property.type == "Identifier" && + node.expression.callee.property.name == "defineLazyScriptGetter" + ) { + // The case where we have a single symbol as a string has already been + // handled by the regexp, so we have an array of symbols here. + return node.expression.arguments[1].elements.map(n => ({ + name: n.value, + writable: true, + explicit: true, + })); + } + + return []; +} + +/** + * Attempts to convert an AssignmentExpression into a global variable + * definition if it applies to `this` in the global scope. + * + * @param {Object} node + * The AST node to convert. + * @param {boolean} isGlobal + * True if the current node is in the global scope. + * + * @return {Array} + * An array of objects that contain details about the globals: + * - {String} name + * The name of the global. + * - {Boolean} writable + * If the global is writeable or not. + */ +function convertThisAssignmentExpressionToGlobals(node, isGlobal) { + if ( + isGlobal && + node.expression.left && + node.expression.left.object && + node.expression.left.object.type === "ThisExpression" && + node.expression.left.property && + node.expression.left.property.type === "Identifier" + ) { + return [{ name: node.expression.left.property.name, writable: true }]; + } + return []; +} + +/** + * Attempts to convert an ExpressionStatement to likely global variable + * definitions. + * + * @param {Object} node + * The AST node to convert. + * @param {boolean} isGlobal + * True if the current node is in the global scope. + * + * @return {Array} + * An array of objects that contain details about the globals: + * - {String} name + * The name of the global. + * - {Boolean} writable + * If the global is writeable or not. + */ +function convertWorkerExpressionToGlobals(node, isGlobal, dirname) { + let results = []; + let expr = node.expression; + + if ( + node.expression.type === "CallExpression" && + expr.callee && + expr.callee.type === "Identifier" && + expr.callee.name === "importScripts" + ) { + for (var arg of expr.arguments) { + var match = arg.value && arg.value.match(workerImportFilenameMatch); + if (match) { + if (!match[1]) { + let filePath = path.resolve(dirname, match[2]); + if (fs.existsSync(filePath)) { + let additionalGlobals = module.exports.getGlobalsForFile(filePath); + results = results.concat(additionalGlobals); + } + } + // Import with relative/absolute path should explicitly use + // `import-globals-from` comment. + } + } + } + + return results; +} + +/** + * Attempts to load the globals for a given script. + * + * @param {string} src + * The source path or url of the script to look for. + * @param {string} type + * The type of the current file (script/module). + * @param {string} [dir] + * The directory of the current file. + * @returns {object[]} + * An array of objects with details of the globals in them. + */ +function getGlobalsForScript(src, type, dir) { + let scriptName; + if (src.includes("http:")) { + // We don't handle this currently as the paths are complex to match. + } else if (src.startsWith("chrome://mochikit/content/")) { + // Various ways referencing test files. + src = src.replace("chrome://mochikit/content/", "/"); + scriptName = path.join(helpers.rootDir, "testing", "mochitest", src); + } else if (src.startsWith("chrome://mochitests/content/browser")) { + src = src.replace("chrome://mochitests/content/browser", ""); + scriptName = path.join(helpers.rootDir, src); + } else if (src.includes("SimpleTest")) { + // This is another way of referencing test files... + scriptName = path.join(helpers.rootDir, "testing", "mochitest", src); + } else if (src.startsWith("/tests/")) { + scriptName = path.join(helpers.rootDir, src.substring(7)); + } else if (dir) { + // Fallback to hoping this is a relative path. + scriptName = path.join(dir, src); + } + if (scriptName && fs.existsSync(scriptName)) { + return module.exports.getGlobalsForFile(scriptName, { + ecmaVersion: helpers.getECMAVersion(), + sourceType: type, + }); + } + return []; +} + +/** + * 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} filePath + * The absolute path of the file being parsed. + */ +function GlobalsForNode(filePath, context) { + this.path = filePath; + this.context = context; + + if (this.path) { + this.dirname = path.dirname(this.path); + } else { + this.dirname = null; + } +} + +GlobalsForNode.prototype = { + Program(node) { + let globals = []; + for (let comment of node.comments) { + if (comment.type !== "Block") { + continue; + } + let value = comment.value.trim(); + value = value.replace(/\n/g, ""); + + // We have to discover any globals that ESLint would have defined through + // comment directives. + 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, + }); + } + // We matched globals, so we won't match import-globals-from. + continue; + } + + match = /^import-globals-from\s+(.+)$/.exec(value); + if (!match) { + continue; + } + + if (!this.dirname) { + // If this is testing context without path, ignore import. + return globals; + } + + let filePath = match[1].trim(); + + if (filePath.endsWith(".mjs")) { + if (this.context) { + this.context.report( + comment, + "import-globals-from does not support module files - use a direct import instead" + ); + } else { + // Fall back to throwing an error, as we do not have a context in all situations, + // e.g. when loading the environment. + throw new Error( + "import-globals-from does not support module files - use a direct import instead" + ); + } + continue; + } + + if (!path.isAbsolute(filePath)) { + filePath = path.resolve(this.dirname, filePath); + } else { + filePath = path.join(helpers.rootDir, filePath); + } + globals = globals.concat(module.exports.getGlobalsForFile(filePath)); + } + + return globals; + }, + + ExpressionStatement(node, parents, globalScope) { + let isGlobal = helpers.getIsGlobalThis(parents); + let globals = []; + + // Note: We check the expression types here and only call the necessary + // functions to aid performance. + if (node.expression.type === "AssignmentExpression") { + globals = convertThisAssignmentExpressionToGlobals(node, isGlobal); + } else if (node.expression.type === "CallExpression") { + globals = convertCallExpressionToGlobals(node, isGlobal); + } + + // Here we assume that if importScripts is set in the global scope, then + // this is a worker. It would be nice if eslint gave us a way of getting + // the environment directly. + // + // If this is testing context without path, ignore import. + if (globalScope && globalScope.set.get("importScripts") && this.dirname) { + let workerDetails = convertWorkerExpressionToGlobals( + node, + isGlobal, + this.dirname + ); + globals = globals.concat(workerDetails); + } + + return globals; + }, +}; + +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} filePath + * The absolute path of the file to be parsed. + * @param {Object} astOptions + * Extra options to pass to the parser. + * @return {Array} + * An array of objects that contain details about the globals: + * - {String} name + * The name of the global. + * - {Boolean} writable + * If the global is writeable or not. + */ + getGlobalsForFile(filePath, astOptions = {}) { + if (globalCache.has(filePath)) { + return globalCache.get(filePath); + } + + if (globalDiscoveryInProgressForFiles.has(filePath)) { + // We're already processing this file, so return an empty set for now - + // the initial processing will pick up on the globals for this file. + return []; + } + globalDiscoveryInProgressForFiles.add(filePath); + + let content = fs.readFileSync(filePath, "utf8"); + + // Parse the content into an AST + let { ast, scopeManager, visitorKeys } = helpers.parseCode( + content, + astOptions + ); + + // Discover global declarations + 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(filePath); + + helpers.walkAST(ast, visitorKeys, (type, node, parents) => { + if (type in handler) { + let newGlobals = handler[type](node, parents, globalScope); + globals.push.apply(globals, newGlobals); + } + }); + + globalCache.set(filePath, globals); + + globalDiscoveryInProgressForFiles.delete(filePath); + return globals; + }, + + /** + * Returns all globals for a code. + * This is only for testing. + * + * @param {String} code + * The JS code + * @param {Object} astOptions + * Extra options to pass to the parser. + * @return {Array} + * An array of objects that contain details about the globals: + * - {String} name + * The name of the global. + * - {Boolean} writable + * If the global is writeable or not. + */ + getGlobalsForCode(code, astOptions = {}) { + // Parse the content into an AST + let { ast, scopeManager, visitorKeys } = helpers.parseCode( + code, + astOptions, + { useBabel: false } + ); + + // Discover global declarations + 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(null); + + helpers.walkAST(ast, visitorKeys, (type, node, parents) => { + if (type in handler) { + let newGlobals = handler[type](node, parents, globalScope); + globals.push.apply(globals, newGlobals); + } + }); + + return globals; + }, + + /** + * Returns all the globals for an html file that are defined by imported + * scripts (i.e. <script src="foo.js">). + * + * This function will cache results for one html file only - we expect + * this to be called sequentially for each chunk of a HTML file, rather + * than chucks of different files in random order. + * + * @param {String} filePath + * The absolute path of the file to be parsed. + * @return {Array} + * An array of objects that contain details about the globals: + * - {String} name + * The name of the global. + * - {Boolean} writable + * If the global is writeable or not. + */ + getImportedGlobalsForHTMLFile(filePath) { + if (lastHTMLGlobals.filename === filePath) { + return lastHTMLGlobals.globals; + } + + let dir = path.dirname(filePath); + let globals = []; + + let content = fs.readFileSync(filePath, "utf8"); + let scriptSrcs = []; + + // We use htmlparser as this ensures we find the script tags correctly. + let parser = new htmlparser.Parser( + { + onopentag(name, attribs) { + if (name === "script" && "src" in attribs) { + scriptSrcs.push({ + src: attribs.src, + type: + "type" in attribs && attribs.type == "module" + ? "module" + : "script", + }); + } + }, + }, + { + xmlMode: filePath.endsWith("xhtml"), + } + ); + + parser.parseComplete(content); + + for (let script of scriptSrcs) { + // Ensure that the script src isn't just "". + if (!script.src) { + continue; + } + globals.push(...getGlobalsForScript(script.src, script.type, dir)); + } + + lastHTMLGlobals.filePath = filePath; + return (lastHTMLGlobals.globals = 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(); + }, + }; + let filename = context.getFilename(); + + let extraHTMLGlobals = []; + if (filename.endsWith(".html") || filename.endsWith(".xhtml")) { + extraHTMLGlobals = module.exports.getImportedGlobalsForHTMLFile(filename); + } + + // Install thin wrappers around GlobalsForNode + let handler = new GlobalsForNode(helpers.getAbsoluteFilePath(context)); + + for (let type of Object.keys(GlobalsForNode.prototype)) { + parser[type] = function (node) { + if (type === "Program") { + globalScope = context.getScope(); + helpers.addGlobals(extraHTMLGlobals, globalScope); + } + let globals = handler[type](node, context.getAncestors(), globalScope); + helpers.addGlobals( + globals, + globalScope, + node.type !== "Program" && node + ); + }; + } + + return parser; + }, +}; |