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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 | 359 |
1 files changed, 359 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..cb1b0d5f66 --- /dev/null +++ b/tools/lint/eslint/eslint-plugin-mozilla/lib/globals.js @@ -0,0 +1,359 @@ +/** + * @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"); + +/** + * 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 xul 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 = {}; + +/** + * 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) { + this.path = filePath; + this.dirname = path.dirname(this.path); +} + +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; + } + + let filePath = match[1].trim(); + + if (!path.isAbsolute(filePath)) { + filePath = path.resolve(this.dirname, filePath); + } + globals = globals.concat(module.exports.getGlobalsForFile(filePath)); + } + + return globals; + }, + + ExpressionStatement(node, parents, globalScope) { + let isGlobal = helpers.getIsGlobalScope(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 = helpers.convertThisAssignmentExpressionToGlobals( + node, + isGlobal + ); + } else if (node.expression.type === "CallExpression") { + globals = helpers.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 (globalScope && globalScope.set.get("importScripts")) { + let workerDetails = helpers.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 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; + } + let scriptName; + if (script.src.includes("http:")) { + // We don't handle this currently as the paths are complex to match. + } else if (script.src.includes("chrome")) { + // This is one way of referencing test files. + script.src = script.src.replace("chrome://mochikit/content/", "/"); + scriptName = path.join( + helpers.rootDir, + "testing", + "mochitest", + script.src + ); + } else if (script.src.includes("SimpleTest")) { + // This is another way of referencing test files... + scriptName = path.join( + helpers.rootDir, + "testing", + "mochitest", + script.src + ); + } else if (script.src.startsWith("/tests/")) { + scriptName = path.join(helpers.rootDir, script.src.substring(7)); + } else { + // Fallback to hoping this is a relative path. + scriptName = path.join(dir, script.src); + } + if (scriptName && fs.existsSync(scriptName)) { + globals.push( + ...module.exports.getGlobalsForFile(scriptName, { + ecmaVersion: helpers.getECMAVersion(), + sourceType: script.type, + }) + ); + } + } + + 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; + }, +}; |