/** * @fileoverview Main Linter Class * @author Gyandeep Singh */ "use strict"; //------------------------------------------------------------------------------ // Requirements //------------------------------------------------------------------------------ const eslintScope = require("eslint-scope"), evk = require("eslint-visitor-keys"), levn = require("levn"), lodash = require("lodash"), blankScriptAST = require("../conf/blank-script.json"), defaultConfig = require("../conf/default-config-options.js"), CodePathAnalyzer = require("./code-path-analysis/code-path-analyzer"), ConfigOps = require("./config/config-ops"), validator = require("./config/config-validator"), Environments = require("./config/environments"), applyDisableDirectives = require("./util/apply-disable-directives"), createEmitter = require("./util/safe-emitter"), NodeEventGenerator = require("./util/node-event-generator"), SourceCode = require("./util/source-code"), Traverser = require("./util/traverser"), createReportTranslator = require("./report-translator"), Rules = require("./rules"), timing = require("./timing"), astUtils = require("./ast-utils"), pkg = require("../package.json"), SourceCodeFixer = require("./util/source-code-fixer"); const debug = require("debug")("eslint:linter"); const MAX_AUTOFIX_PASSES = 10; //------------------------------------------------------------------------------ // Typedefs //------------------------------------------------------------------------------ /** * The result of a parsing operation from parseForESLint() * @typedef {Object} CustomParseResult * @property {ASTNode} ast The ESTree AST Program node. * @property {Object} services An object containing additional services related * to the parser. * @property {ScopeManager|null} scopeManager The scope manager object of this AST. * @property {Object|null} visitorKeys The visitor keys to traverse this AST. */ /** * @typedef {Object} DisableDirective * @property {("disable"|"enable"|"disable-line"|"disable-next-line")} type * @property {number} line * @property {number} column * @property {(string|null)} ruleId */ //------------------------------------------------------------------------------ // Helpers //------------------------------------------------------------------------------ /** * Parses a list of "name:boolean_value" or/and "name" options divided by comma or * whitespace. * @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) { const items = {}; // Collapse whitespace around `:` and `,` to make parsing easier string = string.replace(/\s*([:,])\s*/g, "$1"); string.split(/\s|,+/).forEach(name => { if (!name) { return; } const pos = name.indexOf(":"); let value; if (pos !== -1) { value = name.slice(pos + 1); name = name.slice(0, pos); } items[name] = { value: (value === "true"), comment }; }); return items; } /** * Parses a JSON-like config. * @param {string} string The string to parse. * @param {Object} location Start line and column of comments for potential error message. * @returns {({success: true, config: Object}|{success: false, error: Problem})} Result map object */ function parseJsonConfig(string, location) { let items = {}; // Parses a JSON-like comment by the same way as parsing CLI option. try { items = levn.parse("Object", string) || {}; // Some tests say that it should ignore invalid comments such as `/*eslint no-alert:abc*/`. // Also, commaless notations have invalid severity: // "no-alert: 2 no-console: 2" --> {"no-alert": "2 no-console: 2"} // Should ignore that case as well. if (ConfigOps.isEverySeverityValid(items)) { return { success: true, config: items }; } } catch (ex) { // ignore to parse the string by a fallback. } /* * Optionator cannot parse commaless notations. * But we are supporting that. So this is a fallback for that. */ items = {}; string = string.replace(/([a-zA-Z0-9\-/]+):/g, "\"$1\":").replace(/(]|[0-9])\s+(?=")/, "$1,"); try { items = JSON.parse(`{${string}}`); } catch (ex) { return { success: false, error: { ruleId: null, fatal: true, severity: 2, source: null, message: `Failed to parse JSON from '${string}': ${ex.message}`, line: location.start.line, column: location.start.column + 1 } }; } return { success: true, config: items }; } /** * Parses a config of values separated by comma. * @param {string} string The string to parse. * @returns {Object} Result map of values and true values */ function parseListConfig(string) { const items = {}; // Collapse whitespace around , string = string.replace(/\s*,\s*/g, ","); string.split(/,+/).forEach(name => { name = name.trim(); if (!name) { return; } items[name] = true; }); return items; } /** * Ensures that variables representing built-in properties of the Global Object, * and any globals declared by special block comments, are present in the global * scope. * @param {Scope} globalScope The global scope. * @param {Object} config The existing configuration data. * @param {Environments} envContext Env context * @returns {void} */ function addDeclaredGlobals(globalScope, config, envContext) { const declaredGlobals = {}, exportedGlobals = {}, explicitGlobals = {}, builtin = envContext.get("builtin"); Object.assign(declaredGlobals, builtin); Object.keys(config.env).filter(name => config.env[name]).forEach(name => { const env = envContext.get(name), environmentGlobals = env && env.globals; if (environmentGlobals) { Object.assign(declaredGlobals, environmentGlobals); } }); Object.assign(exportedGlobals, config.exported); Object.assign(declaredGlobals, config.globals); Object.assign(explicitGlobals, config.astGlobals); Object.keys(declaredGlobals).forEach(name => { let variable = globalScope.set.get(name); if (!variable) { variable = new eslintScope.Variable(name, globalScope); variable.eslintExplicitGlobal = false; globalScope.variables.push(variable); globalScope.set.set(name, variable); } variable.writeable = declaredGlobals[name]; }); Object.keys(explicitGlobals).forEach(name => { let variable = globalScope.set.get(name); if (!variable) { variable = new eslintScope.Variable(name, globalScope); variable.eslintExplicitGlobal = true; variable.eslintExplicitGlobalComment = explicitGlobals[name].comment; globalScope.variables.push(variable); globalScope.set.set(name, variable); } variable.writeable = explicitGlobals[name].value; }); // mark all exported variables as such Object.keys(exportedGlobals).forEach(name => { const variable = globalScope.set.get(name); if (variable) { variable.eslintUsed = true; } }); /* * "through" contains all references which definitions cannot be found. * Since we augment the global scope using configuration, we need to update * references and remove the ones that were added by configuration. */ globalScope.through = globalScope.through.filter(reference => { const name = reference.identifier.name; const variable = globalScope.set.get(name); if (variable) { /* * Links the variable and the reference. * And this reference is removed from `Scope#through`. */ reference.resolved = variable; variable.references.push(reference); return false; } return true; }); } /** * Creates a collection of disable directives from a comment * @param {("disable"|"enable"|"disable-line"|"disable-next-line")} type The type of directive comment * @param {{line: number, column: number}} loc The 0-based location of the comment token * @param {string} value The value after the directive in the comment * comment specified no specific rules, so it applies to all rules (e.g. `eslint-disable`) * @returns {DisableDirective[]} Directives from the comment */ function createDisableDirectives(type, loc, value) { const ruleIds = Object.keys(parseListConfig(value)); const directiveRules = ruleIds.length ? ruleIds : [null]; return directiveRules.map(ruleId => ({ type, line: loc.line, column: loc.column + 1, ruleId })); } /** * Parses comments in file to extract file-specific config of rules, globals * and environments and merges them with global config; also code blocks * where reporting is disabled or enabled and merges them with reporting config. * @param {string} filename The file being checked. * @param {ASTNode} ast The top node of the AST. * @param {Object} config The existing configuration data. * @param {function(string): {create: Function}} ruleMapper A map from rule IDs to defined rules * @returns {{config: Object, problems: Problem[], disableDirectives: DisableDirective[]}} * Modified config object, along with any problems encountered while parsing config comments */ function modifyConfigsFromComments(filename, ast, config, ruleMapper) { const commentConfig = { exported: {}, astGlobals: {}, rules: {}, env: {} }; const commentRules = {}; const problems = []; const disableDirectives = []; ast.comments.filter(token => token.type !== "Shebang").forEach(comment => { let value = comment.value.trim(); const match = /^(eslint(-\w+){0,3}|exported|globals?)(\s|$)/.exec(value); if (match) { value = value.slice(match.index + match[1].length); if (comment.type === "Block") { switch (match[1]) { case "exported": Object.assign(commentConfig.exported, parseBooleanConfig(value, comment)); break; case "globals": case "global": Object.assign(commentConfig.astGlobals, parseBooleanConfig(value, comment)); break; case "eslint-disable": [].push.apply(disableDirectives, createDisableDirectives("disable", comment.loc.start, value)); break; case "eslint-enable": [].push.apply(disableDirectives, createDisableDirectives("enable", comment.loc.start, value)); break; case "eslint": { const parseResult = parseJsonConfig(value, comment.loc); if (parseResult.success) { Object.keys(parseResult.config).forEach(name => { const ruleValue = parseResult.config[name]; try { validator.validateRuleOptions(ruleMapper(name), name, ruleValue); } catch (err) { problems.push({ ruleId: name, severity: 2, source: null, message: err.message, line: comment.loc.start.line, column: comment.loc.start.column + 1, endLine: comment.loc.end.line, endColumn: comment.loc.end.column + 1, nodeType: null }); } commentRules[name] = ruleValue; }); } else { problems.push(parseResult.error); } break; } // no default } } else { // comment.type === "Line" if (match[1] === "eslint-disable-line") { [].push.apply(disableDirectives, createDisableDirectives("disable-line", comment.loc.start, value)); } else if (match[1] === "eslint-disable-next-line") { [].push.apply(disableDirectives, createDisableDirectives("disable-next-line", comment.loc.start, value)); } } } }); Object.assign(commentConfig.rules, commentRules); return { config: ConfigOps.merge(config, commentConfig), problems, disableDirectives }; } /** * Normalize ECMAScript version from the initial config * @param {number} ecmaVersion ECMAScript version from the initial config * @param {boolean} isModule Whether the source type is module or not * @returns {number} normalized ECMAScript version */ function normalizeEcmaVersion(ecmaVersion, isModule) { // Need at least ES6 for modules if (isModule && (!ecmaVersion || ecmaVersion < 6)) { ecmaVersion = 6; } /* * Calculate ECMAScript edition number from official year version starting with * ES2015, which corresponds with ES6 (or a difference of 2009). */ if (ecmaVersion >= 2015) { ecmaVersion -= 2009; } return ecmaVersion; } /** * Process initial config to make it safe to extend by file comment config * @param {Object} config Initial config * @param {Environments} envContext Env context * @returns {Object} Processed config */ function prepareConfig(config, envContext) { config.globals = config.globals || {}; const copiedRules = {}; let parserOptions = {}; if (typeof config.rules === "object") { Object.keys(config.rules).forEach(k => { const rule = config.rules[k]; if (rule === null) { throw new Error(`Invalid config for rule '${k}'.`); } if (Array.isArray(rule)) { copiedRules[k] = rule.slice(); } else { copiedRules[k] = rule; } }); } // merge in environment parserOptions if (typeof config.env === "object") { Object.keys(config.env).forEach(envName => { const env = envContext.get(envName); if (config.env[envName] && env && env.parserOptions) { parserOptions = ConfigOps.merge(parserOptions, env.parserOptions); } }); } const preparedConfig = { rules: copiedRules, parser: config.parser || defaultConfig.parser, globals: ConfigOps.merge(defaultConfig.globals, config.globals), env: ConfigOps.merge(defaultConfig.env, config.env || {}), settings: ConfigOps.merge(defaultConfig.settings, config.settings || {}), parserOptions: ConfigOps.merge(parserOptions, config.parserOptions || {}) }; const isModule = preparedConfig.parserOptions.sourceType === "module"; if (isModule) { // can't have global return inside of modules preparedConfig.parserOptions.ecmaFeatures = Object.assign({}, preparedConfig.parserOptions.ecmaFeatures, { globalReturn: false }); } preparedConfig.parserOptions.ecmaVersion = normalizeEcmaVersion(preparedConfig.parserOptions.ecmaVersion, isModule); return preparedConfig; } const eslintEnvPattern = /\/\*\s*eslint-env\s(.+?)\*\//g; /** * Checks whether or not there is a comment which has "eslint-env *" in a given text. * @param {string} text - A source code text to check. * @returns {Object|null} A result of parseListConfig() with "eslint-env *" comment. */ function findEslintEnv(text) { let match, retv; eslintEnvPattern.lastIndex = 0; while ((match = eslintEnvPattern.exec(text))) { retv = Object.assign(retv || {}, parseListConfig(match[1])); } return retv; } /** * Strips Unicode BOM from a given text. * * @param {string} text - A text to strip. * @returns {string} The stripped text. */ function stripUnicodeBOM(text) { /* * Check Unicode BOM. * In JavaScript, string data is stored as UTF-16, so BOM is 0xFEFF. * http://www.ecma-international.org/ecma-262/6.0/#sec-unicode-format-control-characters */ if (text.charCodeAt(0) === 0xFEFF) { return text.slice(1); } return text; } /** * Get the options for a rule (not including severity), if any * @param {Array|number} ruleConfig rule configuration * @returns {Array} of rule options, empty Array if none */ function getRuleOptions(ruleConfig) { if (Array.isArray(ruleConfig)) { return ruleConfig.slice(1); } return []; } /** * Analyze scope of the given AST. * @param {ASTNode} ast The `Program` node to analyze. * @param {Object} parserOptions The parser options. * @param {Object} visitorKeys The visitor keys. * @returns {ScopeManager} The analysis result. */ function analyzeScope(ast, parserOptions, visitorKeys) { const ecmaFeatures = parserOptions.ecmaFeatures || {}; const ecmaVersion = parserOptions.ecmaVersion || 5; return eslintScope.analyze(ast, { ignoreEval: true, nodejsScope: ecmaFeatures.globalReturn, impliedStrict: ecmaFeatures.impliedStrict, ecmaVersion, sourceType: parserOptions.sourceType || "script", childVisitorKeys: visitorKeys || evk.KEYS, fallback: Traverser.getKeys }); } /** * Parses text into an AST. Moved out here because the try-catch prevents * optimization of functions, so it's best to keep the try-catch as isolated * as possible * @param {string} text The text to parse. * @param {Object} providedParserOptions Options to pass to the parser * @param {Object} parser The parser module * @param {string} filePath The path to the file being parsed. * @returns {{success: false, error: Problem}|{success: true, sourceCode: SourceCode}} * An object containing the AST and parser services if parsing was successful, or the error if parsing failed * @private */ function parse(text, providedParserOptions, parser, filePath) { const textToParse = stripUnicodeBOM(text).replace(astUtils.SHEBANG_MATCHER, (match, captured) => `//${captured}`); const parserOptions = Object.assign({}, providedParserOptions, { loc: true, range: true, raw: true, tokens: true, comment: true, eslintVisitorKeys: true, eslintScopeManager: true, filePath }); /* * Check for parsing errors first. If there's a parsing error, nothing * else can happen. However, a parsing error does not throw an error * from this method - it's just considered a fatal error message, a * problem that ESLint identified just like any other. */ try { const parseResult = (typeof parser.parseForESLint === "function") ? parser.parseForESLint(textToParse, parserOptions) : { ast: parser.parse(textToParse, parserOptions) }; const ast = parseResult.ast; const parserServices = parseResult.services || {}; const visitorKeys = parseResult.visitorKeys || evk.KEYS; const scopeManager = parseResult.scopeManager || analyzeScope(ast, parserOptions, visitorKeys); return { success: true, /* * Save all values that `parseForESLint()` returned. * If a `SourceCode` object is given as the first parameter instead of source code text, * linter skips the parsing process and reuses the source code object. * In that case, linter needs all the values that `parseForESLint()` returned. */ sourceCode: new SourceCode({ text, ast, parserServices, scopeManager, visitorKeys }) }; } catch (ex) { // If the message includes a leading line number, strip it: const message = `Parsing error: ${ex.message.replace(/^line \d+:/i, "").trim()}`; const source = ex.lineNumber ? SourceCode.splitLines(text)[ex.lineNumber - 1] : null; return { success: false, error: { ruleId: null, fatal: true, severity: 2, source, message, line: ex.lineNumber, column: ex.column } }; } } /** * Gets the scope for the current node * @param {ScopeManager} scopeManager The scope manager for this AST * @param {ASTNode} currentNode The node to get the scope of * @param {number} ecmaVersion The `ecmaVersion` setting that this code was parsed with * @returns {eslint-scope.Scope} The scope information for this node */ function getScope(scopeManager, currentNode, ecmaVersion) { let initialNode; // if current node introduces a scope, add it to the list if ( ["FunctionDeclaration", "FunctionExpression", "ArrowFunctionExpression"].indexOf(currentNode.type) >= 0 || ecmaVersion >= 6 && ["BlockStatement", "SwitchStatement", "CatchClause"].indexOf(currentNode.type) >= 0 ) { initialNode = currentNode; } else { initialNode = currentNode.parent; } // Ascend the current node's parents for (let node = initialNode; node; node = node.parent) { // Get the innermost scope const scope = scopeManager.acquire(node, true); if (scope) { if (scope.type === "function-expression-name") { return scope.childScopes[0]; } return scope; } } return scopeManager.scopes[0]; } /** * Marks a variable as used in the current scope * @param {ScopeManager} scopeManager The scope manager for this AST. The scope may be mutated by this function. * @param {ASTNode} currentNode The node currently being traversed * @param {Object} parserOptions The options used to parse this text * @param {string} name The name of the variable that should be marked as used. * @returns {boolean} True if the variable was found and marked as used, false if not. */ function markVariableAsUsed(scopeManager, currentNode, parserOptions, name) { const hasGlobalReturn = parserOptions.ecmaFeatures && parserOptions.ecmaFeatures.globalReturn; const specialScope = hasGlobalReturn || parserOptions.sourceType === "module"; const currentScope = getScope(scopeManager, currentNode, parserOptions.ecmaVersion); // Special Node.js scope means we need to start one level deeper const initialScope = currentScope.type === "global" && specialScope ? currentScope.childScopes[0] : currentScope; for (let scope = initialScope; scope; scope = scope.upper) { const variable = scope.variables.find(scopeVar => scopeVar.name === name); if (variable) { variable.eslintUsed = true; return true; } } return false; } // methods that exist on SourceCode object const DEPRECATED_SOURCECODE_PASSTHROUGHS = { getSource: "getText", getSourceLines: "getLines", getAllComments: "getAllComments", getNodeByRangeIndex: "getNodeByRangeIndex", getComments: "getComments", getCommentsBefore: "getCommentsBefore", getCommentsAfter: "getCommentsAfter", getCommentsInside: "getCommentsInside", getJSDocComment: "getJSDocComment", getFirstToken: "getFirstToken", getFirstTokens: "getFirstTokens", getLastToken: "getLastToken", getLastTokens: "getLastTokens", getTokenAfter: "getTokenAfter", getTokenBefore: "getTokenBefore", getTokenByRangeStart: "getTokenByRangeStart", getTokens: "getTokens", getTokensAfter: "getTokensAfter", getTokensBefore: "getTokensBefore", getTokensBetween: "getTokensBetween" }; const BASE_TRAVERSAL_CONTEXT = Object.freeze( Object.keys(DEPRECATED_SOURCECODE_PASSTHROUGHS).reduce( (contextInfo, methodName) => Object.assign(contextInfo, { [methodName]() { const sourceCode = this.getSourceCode(); return sourceCode[DEPRECATED_SOURCECODE_PASSTHROUGHS[methodName]].apply(sourceCode, arguments); } }), {} ) ); const lastSourceCodes = new WeakMap(); //------------------------------------------------------------------------------ // Public Interface //------------------------------------------------------------------------------ /** * Object that is responsible for verifying JavaScript text * @name eslint */ module.exports = class Linter { constructor() { lastSourceCodes.set(this, null); this.version = pkg.version; this.rules = new Rules(); this._parsers = new Map(); this.environments = new Environments(); } /** * Configuration object for the `verify` API. A JS representation of the eslintrc files. * @typedef {Object} ESLintConfig * @property {Object} rules The rule configuration to verify against. * @property {string} [parser] Parser to use when generatig the AST. * @property {Object} [parserOptions] Options for the parsed used. * @property {Object} [settings] Global settings passed to each rule. * @property {Object} [env] The environment to verify in. * @property {Object} [globals] Available globals to the code. */ /** * Same as linter.verify, except without support for processors. * @param {string|SourceCode} textOrSourceCode The text to parse or a SourceCode object. * @param {ESLintConfig} config An ESLintConfig instance to configure everything. * @param {(string|Object)} [filenameOrOptions] The optional filename of the file being checked. * If this is not set, the filename will default to '<input>' in the rule context. If * an object, then it has "filename", "saveState", and "allowInlineConfig" properties. * @param {boolean} [filenameOrOptions.allowInlineConfig=true] Allow/disallow inline comments' ability to change config once it is set. Defaults to true if not supplied. * Useful if you want to validate JS without comments overriding rules. * @param {boolean} [filenameOrOptions.reportUnusedDisableDirectives=false] Adds reported errors for unused * eslint-disable directives * @returns {Object[]} The results as an array of messages or null if no messages. */ _verifyWithoutProcessors(textOrSourceCode, config, filenameOrOptions) { let text, allowInlineConfig, providedFilename, reportUnusedDisableDirectives; // evaluate arguments if (typeof filenameOrOptions === "object") { providedFilename = filenameOrOptions.filename; allowInlineConfig = filenameOrOptions.allowInlineConfig; reportUnusedDisableDirectives = filenameOrOptions.reportUnusedDisableDirectives; } else { providedFilename = filenameOrOptions; } if (typeof textOrSourceCode === "string") { lastSourceCodes.set(this, null); text = textOrSourceCode; } else { lastSourceCodes.set(this, textOrSourceCode); text = textOrSourceCode.text; } const filename = typeof providedFilename === "string" ? providedFilename : "<input>"; // search and apply "eslint-env *". const envInFile = findEslintEnv(text); config = Object.assign({}, config); if (envInFile) { if (config.env) { config.env = Object.assign({}, config.env, envInFile); } else { config.env = envInFile; } } // process initial config to make it safe to extend config = prepareConfig(config, this.environments); if (!lastSourceCodes.get(this)) { // there's no input, just exit here if (text.trim().length === 0) { lastSourceCodes.set(this, new SourceCode(text, blankScriptAST)); return []; } let parser; try { parser = this._parsers.get(config.parser) || require(config.parser); } catch (ex) { return [{ ruleId: null, fatal: true, severity: 2, source: null, message: ex.message, line: 0, column: 0 }]; } const parseResult = parse( text, config.parserOptions, parser, filename ); if (!parseResult.success) { return [parseResult.error]; } lastSourceCodes.set(this, parseResult.sourceCode); } else { /* * If the given source code object as the first argument does not have scopeManager, analyze the scope. * This is for backward compatibility (SourceCode is frozen so it cannot rebind). */ const lastSourceCode = lastSourceCodes.get(this); if (!lastSourceCode.scopeManager) { lastSourceCodes.set(this, new SourceCode({ text: lastSourceCode.text, ast: lastSourceCode.ast, parserServices: lastSourceCode.parserServices, visitorKeys: lastSourceCode.visitorKeys, scopeManager: analyzeScope(lastSourceCode.ast, config.parserOptions) })); } } const problems = []; const sourceCode = lastSourceCodes.get(this); let disableDirectives; // parse global comments and modify config if (allowInlineConfig !== false) { const modifyConfigResult = modifyConfigsFromComments(filename, sourceCode.ast, config, ruleId => this.rules.get(ruleId)); config = modifyConfigResult.config; modifyConfigResult.problems.forEach(problem => problems.push(problem)); disableDirectives = modifyConfigResult.disableDirectives; } else { disableDirectives = []; } const emitter = createEmitter(); const traverser = new Traverser(); const scopeManager = sourceCode.scopeManager; /* * Create a frozen object with the ruleContext properties and methods that are shared by all rules. * All rule contexts will inherit from this object. This avoids the performance penalty of copying all the * properties once for each rule. */ const sharedTraversalContext = Object.freeze( Object.assign( Object.create(BASE_TRAVERSAL_CONTEXT), { getAncestors: () => traverser.parents(), getDeclaredVariables: scopeManager.getDeclaredVariables.bind(scopeManager), getFilename: () => filename, getScope: () => getScope(scopeManager, traverser.current(), config.parserOptions.ecmaVersion), getSourceCode: () => sourceCode, markVariableAsUsed: name => markVariableAsUsed(scopeManager, traverser.current(), config.parserOptions, name), parserOptions: config.parserOptions, parserPath: config.parser, parserServices: sourceCode.parserServices, settings: config.settings, /** * This is used to avoid breaking rules that used to monkeypatch the `Linter#report` method * by using the `_linter` property on rule contexts. * * This should be removed in a major release after we create a better way to * lint for unused disable comments. * https://github.com/eslint/eslint/issues/9193 */ _linter: { report() {}, on: emitter.on } } ) ); // enable appropriate rules Object.keys(config.rules).forEach(ruleId => { const severity = ConfigOps.getRuleSeverity(config.rules[ruleId]); if (severity === 0) { return; } const rule = this.rules.get(ruleId); const messageIds = rule && rule.meta && rule.meta.messages; let reportTranslator = null; const ruleContext = Object.freeze( Object.assign( Object.create(sharedTraversalContext), { id: ruleId, options: getRuleOptions(config.rules[ruleId]), report() { /* * Create a report translator lazily. * In a vast majority of cases, any given rule reports zero errors on a given * piece of code. Creating a translator lazily avoids the performance cost of * creating a new translator function for each rule that usually doesn't get * called. * * Using lazy report translators improves end-to-end performance by about 3% * with Node 8.4.0. */ if (reportTranslator === null) { reportTranslator = createReportTranslator({ ruleId, severity, sourceCode, messageIds }); } const problem = reportTranslator.apply(null, arguments); if (problem.fix && rule.meta && !rule.meta.fixable) { throw new Error("Fixable rules should export a `meta.fixable` property."); } problems.push(problem); /* * This is used to avoid breaking rules that used monkeypatch Linter, and relied on * `linter.report` getting called with report info every time a rule reports a problem. * To continue to support this, make sure that `context._linter.report` is called every * time a problem is reported by a rule, even though `context._linter` is no longer a * `Linter` instance. * * This should be removed in a major release after we create a better way to * lint for unused disable comments. * https://github.com/eslint/eslint/issues/9193 */ sharedTraversalContext._linter.report( // eslint-disable-line no-underscore-dangle problem.ruleId, problem.severity, { loc: { start: { line: problem.line, column: problem.column - 1 } } }, problem.message ); } } ) ); try { const ruleListeners = rule.create(ruleContext); // add all the selectors from the rule as listeners Object.keys(ruleListeners).forEach(selector => { emitter.on( selector, timing.enabled ? timing.time(ruleId, ruleListeners[selector]) : ruleListeners[selector] ); }); } catch (ex) { ex.message = `Error while loading rule '${ruleId}': ${ex.message}`; throw ex; } }); // augment global scope with declared global variables addDeclaredGlobals(scopeManager.scopes[0], config, this.environments); const eventGenerator = new CodePathAnalyzer(new NodeEventGenerator(emitter)); /* * Each node has a type property. Whenever a particular type of * node is found, an event is fired. This allows any listeners to * automatically be informed that this type of node has been found * and react accordingly. */ traverser.traverse(sourceCode.ast, { enter(node, parent) { node.parent = parent; eventGenerator.enterNode(node); }, leave(node) { eventGenerator.leaveNode(node); }, visitorKeys: sourceCode.visitorKeys }); return applyDisableDirectives({ directives: disableDirectives, problems: problems.sort((problemA, problemB) => problemA.line - problemB.line || problemA.column - problemB.column), reportUnusedDisableDirectives }); } /** * Verifies the text against the rules specified by the second argument. * @param {string|SourceCode} textOrSourceCode The text to parse or a SourceCode object. * @param {ESLintConfig} config An ESLintConfig instance to configure everything. * @param {(string|Object)} [filenameOrOptions] The optional filename of the file being checked. * If this is not set, the filename will default to '<input>' in the rule context. If * an object, then it has "filename", "saveState", and "allowInlineConfig" properties. * @param {boolean} [saveState] Indicates if the state from the last run should be saved. * Mostly useful for testing purposes. * @param {boolean} [filenameOrOptions.allowInlineConfig] Allow/disallow inline comments' ability to change config once it is set. Defaults to true if not supplied. * Useful if you want to validate JS without comments overriding rules. * @param {function(string): string[]} [filenameOrOptions.preprocess] preprocessor for source text. If provided, * this should accept a string of source text, and return an array of code blocks to lint. * @param {function(Array<Object[]>): Object[]} [filenameOrOptions.postprocess] postprocessor for report messages. If provided, * this should accept an array of the message lists for each code block returned from the preprocessor, * apply a mapping to the messages as appropriate, and return a one-dimensional array of messages * @returns {Object[]} The results as an array of messages or null if no messages. */ verify(textOrSourceCode, config, filenameOrOptions) { const preprocess = filenameOrOptions && filenameOrOptions.preprocess || (rawText => [rawText]); const postprocess = filenameOrOptions && filenameOrOptions.postprocess || lodash.flatten; return postprocess( preprocess(textOrSourceCode).map( textBlock => this._verifyWithoutProcessors(textBlock, config, filenameOrOptions) ) ); } /** * Gets the SourceCode object representing the parsed source. * @returns {SourceCode} The SourceCode object. */ getSourceCode() { return lastSourceCodes.get(this); } /** * Defines a new linting rule. * @param {string} ruleId A unique rule identifier * @param {Function} ruleModule Function from context to object mapping AST node types to event handlers * @returns {void} */ defineRule(ruleId, ruleModule) { this.rules.define(ruleId, ruleModule); } /** * Defines many new linting rules. * @param {Object} rulesToDefine map from unique rule identifier to rule * @returns {void} */ defineRules(rulesToDefine) { Object.getOwnPropertyNames(rulesToDefine).forEach(ruleId => { this.defineRule(ruleId, rulesToDefine[ruleId]); }); } /** * Gets an object with all loaded rules. * @returns {Map} All loaded rules */ getRules() { return this.rules.getAllLoadedRules(); } /** * Define a new parser module * @param {any} parserId Name of the parser * @param {any} parserModule The parser object * @returns {void} */ defineParser(parserId, parserModule) { this._parsers.set(parserId, parserModule); } /** * Performs multiple autofix passes over the text until as many fixes as possible * have been applied. * @param {string} text The source text to apply fixes to. * @param {Object} config The ESLint config object to use. * @param {Object} options The ESLint options object to use. * @param {string} options.filename The filename from which the text was read. * @param {boolean} options.allowInlineConfig Flag indicating if inline comments * should be allowed. * @param {boolean|Function} options.fix Determines whether fixes should be applied * @param {Function} options.preprocess preprocessor for source text. If provided, this should * accept a string of source text, and return an array of code blocks to lint. * @param {Function} options.postprocess postprocessor for report messages. If provided, * this should accept an array of the message lists for each code block returned from the preprocessor, * apply a mapping to the messages as appropriate, and return a one-dimensional array of messages * @returns {Object} The result of the fix operation as returned from the * SourceCodeFixer. */ verifyAndFix(text, config, options) { let messages = [], fixedResult, fixed = false, passNumber = 0; const debugTextDescription = options && options.filename || `${text.slice(0, 10)}...`; const shouldFix = options && typeof options.fix !== "undefined" ? options.fix : true; /** * This loop continues until one of the following is true: * * 1. No more fixes have been applied. * 2. Ten passes have been made. * * That means anytime a fix is successfully applied, there will be another pass. * Essentially, guaranteeing a minimum of two passes. */ do { passNumber++; debug(`Linting code for ${debugTextDescription} (pass ${passNumber})`); messages = this.verify(text, config, options); debug(`Generating fixed text for ${debugTextDescription} (pass ${passNumber})`); fixedResult = SourceCodeFixer.applyFixes(text, messages, shouldFix); /* * stop if there are any syntax errors. * 'fixedResult.output' is a empty string. */ if (messages.length === 1 && messages[0].fatal) { break; } // keep track if any fixes were ever applied - important for return value fixed = fixed || fixedResult.fixed; // update to use the fixed output instead of the original text text = fixedResult.output; } while ( fixedResult.fixed && passNumber < MAX_AUTOFIX_PASSES ); /* * If the last result had fixes, we need to lint again to be sure we have * the most up-to-date information. */ if (fixedResult.fixed) { fixedResult.messages = this.verify(text, config, options); } // ensure the last result properly reflects if fixes were done fixedResult.fixed = fixed; fixedResult.output = text; return fixedResult; } };