/** * @fileoverview Main Linter Class * @author Gyandeep Singh * @author aladdin-add */ "use strict"; //------------------------------------------------------------------------------ // Requirements //------------------------------------------------------------------------------ const path = require("path"), eslintScope = require("eslint-scope"), evk = require("eslint-visitor-keys"), espree = require("espree"), lodash = require("lodash"), BuiltInEnvironments = require("../../conf/environments"), pkg = require("../../package.json"), astUtils = require("../shared/ast-utils"), ConfigOps = require("../shared/config-ops"), validator = require("../shared/config-validator"), Traverser = require("../shared/traverser"), { SourceCode } = require("../source-code"), CodePathAnalyzer = require("./code-path-analysis/code-path-analyzer"), applyDisableDirectives = require("./apply-disable-directives"), ConfigCommentParser = require("./config-comment-parser"), NodeEventGenerator = require("./node-event-generator"), createReportTranslator = require("./report-translator"), Rules = require("./rules"), createEmitter = require("./safe-emitter"), SourceCodeFixer = require("./source-code-fixer"), timing = require("./timing"), ruleReplacements = require("../../conf/replacements.json"); const debug = require("debug")("eslint:linter"); const MAX_AUTOFIX_PASSES = 10; const DEFAULT_PARSER_NAME = "espree"; const commentParser = new ConfigCommentParser(); const DEFAULT_ERROR_LOC = { start: { line: 1, column: 0 }, end: { line: 1, column: 1 } }; //------------------------------------------------------------------------------ // Typedefs //------------------------------------------------------------------------------ /** @typedef {InstanceType} ConfigArray */ /** @typedef {InstanceType} ExtractedConfig */ /** @typedef {import("../shared/types").ConfigData} ConfigData */ /** @typedef {import("../shared/types").Environment} Environment */ /** @typedef {import("../shared/types").GlobalConf} GlobalConf */ /** @typedef {import("../shared/types").LintMessage} LintMessage */ /** @typedef {import("../shared/types").ParserOptions} ParserOptions */ /** @typedef {import("../shared/types").Processor} Processor */ /** @typedef {import("../shared/types").Rule} Rule */ /** * @template T * @typedef {{ [P in keyof T]-?: T[P] }} Required */ /** * @typedef {Object} DisableDirective * @property {("disable"|"enable"|"disable-line"|"disable-next-line")} type * @property {number} line * @property {number} column * @property {(string|null)} ruleId */ /** * The private data for `Linter` instance. * @typedef {Object} LinterInternalSlots * @property {ConfigArray|null} lastConfigArray The `ConfigArray` instance that the last `verify()` call used. * @property {SourceCode|null} lastSourceCode The `SourceCode` instance that the last `verify()` call used. * @property {Map} parserMap The loaded parsers. * @property {Rules} ruleMap The loaded rules. */ /** * @typedef {Object} VerifyOptions * @property {boolean} [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. * @property {boolean} [disableFixes] if `true` then the linter doesn't make `fix` * properties into the lint result. * @property {string} [filename] the filename of the source code. * @property {boolean | "off" | "warn" | "error"} [reportUnusedDisableDirectives] Adds reported errors for * unused `eslint-disable` directives. */ /** * @typedef {Object} ProcessorOptions * @property {(filename:string, text:string) => boolean} [filterCodeBlock] the * predicate function that selects adopt code blocks. * @property {Processor["postprocess"]} [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. * @property {Processor["preprocess"]} [preprocess] preprocessor for source text. * If provided, this should accept a string of source text, and return an * array of code blocks to lint. */ /** * @typedef {Object} FixOptions * @property {boolean | ((message: LintMessage) => boolean)} [fix] Determines * whether fixes should be applied. */ /** * @typedef {Object} InternalOptions * @property {string | null} warnInlineConfig The config name what `noInlineConfig` setting came from. If `noInlineConfig` setting didn't exist, this is null. If this is a config name, then the linter warns directive comments. * @property {"off" | "warn" | "error"} reportUnusedDisableDirectives (boolean values were normalized) */ //------------------------------------------------------------------------------ // Helpers //------------------------------------------------------------------------------ /** * 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} configGlobals The globals declared in configuration * @param {{exportedVariables: Object, enabledGlobals: Object}} commentDirectives Directives from comment configuration * @returns {void} */ function addDeclaredGlobals(globalScope, configGlobals, { exportedVariables, enabledGlobals }) { // Define configured global variables. for (const id of new Set([...Object.keys(configGlobals), ...Object.keys(enabledGlobals)])) { /* * `ConfigOps.normalizeConfigGlobal` will throw an error if a configured global value is invalid. However, these errors would * typically be caught when validating a config anyway (validity for inline global comments is checked separately). */ const configValue = configGlobals[id] === void 0 ? void 0 : ConfigOps.normalizeConfigGlobal(configGlobals[id]); const commentValue = enabledGlobals[id] && enabledGlobals[id].value; const value = commentValue || configValue; const sourceComments = enabledGlobals[id] && enabledGlobals[id].comments; if (value === "off") { continue; } let variable = globalScope.set.get(id); if (!variable) { variable = new eslintScope.Variable(id, globalScope); globalScope.variables.push(variable); globalScope.set.set(id, variable); } variable.eslintImplicitGlobalSetting = configValue; variable.eslintExplicitGlobal = sourceComments !== void 0; variable.eslintExplicitGlobalComments = sourceComments; variable.writeable = (value === "writable"); } // mark all exported variables as such Object.keys(exportedVariables).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 missing-rule message. * @param {string} ruleId the ruleId to create * @returns {string} created error message * @private */ function createMissingRuleMessage(ruleId) { return Object.prototype.hasOwnProperty.call(ruleReplacements.rules, ruleId) ? `Rule '${ruleId}' was removed and replaced by: ${ruleReplacements.rules[ruleId].join(", ")}` : `Definition for rule '${ruleId}' was not found.`; } /** * creates a linting problem * @param {Object} options to create linting error * @param {string} [options.ruleId] the ruleId to report * @param {Object} [options.loc] the loc to report * @param {string} [options.message] the error message to report * @param {string} [options.severity] the error message to report * @returns {LintMessage} created problem, returns a missing-rule problem if only provided ruleId. * @private */ function createLintingProblem(options) { const { ruleId = null, loc = DEFAULT_ERROR_LOC, message = createMissingRuleMessage(options.ruleId), severity = 2 } = options; return { ruleId, message, line: loc.start.line, column: loc.start.column + 1, endLine: loc.end.line, endColumn: loc.end.column + 1, severity, nodeType: null }; } /** * Creates a collection of disable directives from a comment * @param {Object} options to create disable directives * @param {("disable"|"enable"|"disable-line"|"disable-next-line")} options.type The type of directive comment * @param {{line: number, column: number}} options.loc The 0-based location of the comment token * @param {string} options.value The value after the directive in the comment * comment specified no specific rules, so it applies to all rules (e.g. `eslint-disable`) * @param {function(string): {create: Function}} options.ruleMapper A map from rule IDs to defined rules * @returns {Object} Directives and problems from the comment */ function createDisableDirectives(options) { const { type, loc, value, ruleMapper } = options; const ruleIds = Object.keys(commentParser.parseListConfig(value)); const directiveRules = ruleIds.length ? ruleIds : [null]; const result = { directives: [], // valid disable directives directiveProblems: [] // problems in directives }; for (const ruleId of directiveRules) { // push to directives, if the rule is defined(including null, e.g. /*eslint enable*/) if (ruleId === null || ruleMapper(ruleId) !== null) { result.directives.push({ type, line: loc.start.line, column: loc.start.column + 1, ruleId }); } else { result.directiveProblems.push(createLintingProblem({ ruleId, loc })); } } return result; } /** * Remove the ignored part from a given directive comment and trim it. * @param {string} value The comment text to strip. * @returns {string} The stripped text. */ function stripDirectiveComment(value) { return value.split(/\s-{2,}\s/u)[0].trim(); } /** * 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 {function(string): {create: Function}} ruleMapper A map from rule IDs to defined rules * @param {string|null} warnInlineConfig If a string then it should warn directive comments as disabled. The string value is the config name what the setting came from. * @returns {{configuredRules: Object, enabledGlobals: {value:string,comment:Token}[], exportedVariables: Object, problems: Problem[], disableDirectives: DisableDirective[]}} * A collection of the directive comments that were found, along with any problems that occurred when parsing */ function getDirectiveComments(filename, ast, ruleMapper, warnInlineConfig) { const configuredRules = {}; const enabledGlobals = Object.create(null); const exportedVariables = {}; const problems = []; const disableDirectives = []; ast.comments.filter(token => token.type !== "Shebang").forEach(comment => { const trimmedCommentText = stripDirectiveComment(comment.value); const match = /^(eslint(?:-env|-enable|-disable(?:(?:-next)?-line)?)?|exported|globals?)(?:\s|$)/u.exec(trimmedCommentText); if (!match) { return; } const directiveText = match[1]; const lineCommentSupported = /^eslint-disable-(next-)?line$/u.test(directiveText); if (comment.type === "Line" && !lineCommentSupported) { return; } if (warnInlineConfig) { const kind = comment.type === "Block" ? `/*${directiveText}*/` : `//${directiveText}`; problems.push(createLintingProblem({ ruleId: null, message: `'${kind}' has no effect because you have 'noInlineConfig' setting in ${warnInlineConfig}.`, loc: comment.loc, severity: 1 })); return; } if (lineCommentSupported && comment.loc.start.line !== comment.loc.end.line) { const message = `${directiveText} comment should not span multiple lines.`; problems.push(createLintingProblem({ ruleId: null, message, loc: comment.loc })); return; } const directiveValue = trimmedCommentText.slice(match.index + directiveText.length); switch (directiveText) { case "eslint-disable": case "eslint-enable": case "eslint-disable-next-line": case "eslint-disable-line": { const directiveType = directiveText.slice("eslint-".length); const options = { type: directiveType, loc: comment.loc, value: directiveValue, ruleMapper }; const { directives, directiveProblems } = createDisableDirectives(options); disableDirectives.push(...directives); problems.push(...directiveProblems); break; } case "exported": Object.assign(exportedVariables, commentParser.parseStringConfig(directiveValue, comment)); break; case "globals": case "global": for (const [id, { value }] of Object.entries(commentParser.parseStringConfig(directiveValue, comment))) { let normalizedValue; try { normalizedValue = ConfigOps.normalizeConfigGlobal(value); } catch (err) { problems.push(createLintingProblem({ ruleId: null, loc: comment.loc, message: err.message })); continue; } if (enabledGlobals[id]) { enabledGlobals[id].comments.push(comment); enabledGlobals[id].value = normalizedValue; } else { enabledGlobals[id] = { comments: [comment], value: normalizedValue }; } } break; case "eslint": { const parseResult = commentParser.parseJsonConfig(directiveValue, comment.loc); if (parseResult.success) { Object.keys(parseResult.config).forEach(name => { const rule = ruleMapper(name); const ruleValue = parseResult.config[name]; if (rule === null) { problems.push(createLintingProblem({ ruleId: name, loc: comment.loc })); return; } try { validator.validateRuleOptions(rule, name, ruleValue); } catch (err) { problems.push(createLintingProblem({ ruleId: name, message: err.message, loc: comment.loc })); // do not apply the config, if found invalid options. return; } configuredRules[name] = ruleValue; }); } else { problems.push(parseResult.error); } break; } // no default } }); return { configuredRules, enabledGlobals, exportedVariables, problems, disableDirectives }; } /** * Normalize ECMAScript version from the initial config * @param {number} ecmaVersion ECMAScript version from the initial config * @returns {number} normalized ECMAScript version */ function normalizeEcmaVersion(ecmaVersion) { /* * Calculate ECMAScript edition number from official year version starting with * ES2015, which corresponds with ES6 (or a difference of 2009). */ return ecmaVersion >= 2015 ? ecmaVersion - 2009 : ecmaVersion; } const eslintEnvPattern = /\/\*\s*eslint-env\s(.+?)\*\//gu; /** * 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)) !== null) { retv = Object.assign( retv || {}, commentParser.parseListConfig(stripDirectiveComment(match[1])) ); } return retv; } /** * Convert "/path/to/" to "". * `CLIEngine#executeOnText()` method gives "/path/to/" if the filename * was omitted because `configArray.extractConfig()` requires an absolute path. * But the linter should pass `` to `RuleContext#getFilename()` in that * case. * Also, code blocks can have their virtual filename. If the parent filename was * ``, the virtual filename is `/0_foo.js` or something like (i.e., * it's not an absolute path). * @param {string} filename The filename to normalize. * @returns {string} The normalized filename. */ function normalizeFilename(filename) { const parts = filename.split(path.sep); const index = parts.lastIndexOf(""); return index === -1 ? filename : parts.slice(index).join(path.sep); } /** * Normalizes the possible options for `linter.verify` and `linter.verifyAndFix` to a * consistent shape. * @param {VerifyOptions} providedOptions Options * @param {ConfigData} config Config. * @returns {Required & InternalOptions} Normalized options */ function normalizeVerifyOptions(providedOptions, config) { const disableInlineConfig = config.noInlineConfig === true; const ignoreInlineConfig = providedOptions.allowInlineConfig === false; const configNameOfNoInlineConfig = config.configNameOfNoInlineConfig ? ` (${config.configNameOfNoInlineConfig})` : ""; let reportUnusedDisableDirectives = providedOptions.reportUnusedDisableDirectives; if (typeof reportUnusedDisableDirectives === "boolean") { reportUnusedDisableDirectives = reportUnusedDisableDirectives ? "error" : "off"; } if (typeof reportUnusedDisableDirectives !== "string") { reportUnusedDisableDirectives = config.reportUnusedDisableDirectives ? "warn" : "off"; } return { filename: normalizeFilename(providedOptions.filename || ""), allowInlineConfig: !ignoreInlineConfig, warnInlineConfig: disableInlineConfig && !ignoreInlineConfig ? `your config${configNameOfNoInlineConfig}` : null, reportUnusedDisableDirectives, disableFixes: Boolean(providedOptions.disableFixes) }; } /** * Combines the provided parserOptions with the options from environments * @param {string} parserName The parser name which uses this options. * @param {ParserOptions} providedOptions The provided 'parserOptions' key in a config * @param {Environment[]} enabledEnvironments The environments enabled in configuration and with inline comments * @returns {ParserOptions} Resulting parser options after merge */ function resolveParserOptions(parserName, providedOptions, enabledEnvironments) { const parserOptionsFromEnv = enabledEnvironments .filter(env => env.parserOptions) .reduce((parserOptions, env) => lodash.merge(parserOptions, env.parserOptions), {}); const mergedParserOptions = lodash.merge(parserOptionsFromEnv, providedOptions || {}); const isModule = mergedParserOptions.sourceType === "module"; if (isModule) { /* * can't have global return inside of modules * TODO: espree validate parserOptions.globalReturn when sourceType is setting to module.(@aladdin-add) */ mergedParserOptions.ecmaFeatures = Object.assign({}, mergedParserOptions.ecmaFeatures, { globalReturn: false }); } /* * TODO: @aladdin-add * 1. for a 3rd-party parser, do not normalize parserOptions * 2. for espree, no need to do this (espree will do it) */ mergedParserOptions.ecmaVersion = normalizeEcmaVersion(mergedParserOptions.ecmaVersion); return mergedParserOptions; } /** * Combines the provided globals object with the globals from environments * @param {Record} providedGlobals The 'globals' key in a config * @param {Environment[]} enabledEnvironments The environments enabled in configuration and with inline comments * @returns {Record} The resolved globals object */ function resolveGlobals(providedGlobals, enabledEnvironments) { return Object.assign( {}, ...enabledEnvironments.filter(env => env.globals).map(env => env.globals), providedGlobals ); } /** * 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 {ParserOptions} parserOptions The parser options. * @param {Record} 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 {Parser} parser The parser to parse. * @param {ParserOptions} providedParserOptions Options to pass to the parser * @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, parser, providedParserOptions, filePath) { const textToParse = stripUnicodeBOM(text).replace(astUtils.shebangPattern, (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+:/iu, "").trim()}`; debug("%s\n%s", message, ex.stack); return { success: false, error: { ruleId: null, fatal: true, severity: 2, 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 * @returns {eslint-scope.Scope} The scope information for this node */ function getScope(scopeManager, currentNode) { // On Program node, get the outermost scope to avoid return Node.js special function scope or ES modules scope. const inner = currentNode.type !== "Program"; for (let node = currentNode; node; node = node.parent) { const scope = scopeManager.acquire(node, inner); 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); // 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; } /** * Runs a rule, and gets its listeners * @param {Rule} rule A normalized rule with a `create` method * @param {Context} ruleContext The context that should be passed to the rule * @returns {Object} A map of selector listeners provided by the rule */ function createRuleListeners(rule, ruleContext) { try { return rule.create(ruleContext); } catch (ex) { ex.message = `Error while loading rule '${ruleContext.id}': ${ex.message}`; throw ex; } } /** * Gets all the ancestors of a given node * @param {ASTNode} node The node * @returns {ASTNode[]} All the ancestor nodes in the AST, not including the provided node, starting * from the root node and going inwards to the parent node. */ function getAncestors(node) { const ancestorsStartingAtParent = []; for (let ancestor = node.parent; ancestor; ancestor = ancestor.parent) { ancestorsStartingAtParent.push(ancestor); } return ancestorsStartingAtParent.reverse(); } // 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](...args) { return this.getSourceCode()[DEPRECATED_SOURCECODE_PASSTHROUGHS[methodName]](...args); } }), {} ) ); /** * Runs the given rules on the given SourceCode object * @param {SourceCode} sourceCode A SourceCode object for the given text * @param {Object} configuredRules The rules configuration * @param {function(string): Rule} ruleMapper A mapper function from rule names to rules * @param {Object} parserOptions The options that were passed to the parser * @param {string} parserName The name of the parser in the config * @param {Object} settings The settings that were enabled in the config * @param {string} filename The reported filename of the code * @param {boolean} disableFixes If true, it doesn't make `fix` properties. * @param {string | undefined} cwd cwd of the cli * @returns {Problem[]} An array of reported problems */ function runRules(sourceCode, configuredRules, ruleMapper, parserOptions, parserName, settings, filename, disableFixes, cwd) { const emitter = createEmitter(); const nodeQueue = []; let currentNode = sourceCode.ast; Traverser.traverse(sourceCode.ast, { enter(node, parent) { node.parent = parent; nodeQueue.push({ isEntering: true, node }); }, leave(node) { nodeQueue.push({ isEntering: false, node }); }, visitorKeys: sourceCode.visitorKeys }); /* * 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: () => getAncestors(currentNode), getDeclaredVariables: sourceCode.scopeManager.getDeclaredVariables.bind(sourceCode.scopeManager), getCwd: () => cwd, getFilename: () => filename, getScope: () => getScope(sourceCode.scopeManager, currentNode), getSourceCode: () => sourceCode, markVariableAsUsed: name => markVariableAsUsed(sourceCode.scopeManager, currentNode, parserOptions, name), parserOptions, parserPath: parserName, parserServices: sourceCode.parserServices, settings } ) ); const lintingProblems = []; Object.keys(configuredRules).forEach(ruleId => { const severity = ConfigOps.getRuleSeverity(configuredRules[ruleId]); // not load disabled rules if (severity === 0) { return; } const rule = ruleMapper(ruleId); if (rule === null) { lintingProblems.push(createLintingProblem({ ruleId })); return; } const messageIds = rule.meta && rule.meta.messages; let reportTranslator = null; const ruleContext = Object.freeze( Object.assign( Object.create(sharedTraversalContext), { id: ruleId, options: getRuleOptions(configuredRules[ruleId]), report(...args) { /* * 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, disableFixes }); } const problem = reportTranslator(...args); if (problem.fix && rule.meta && !rule.meta.fixable) { throw new Error("Fixable rules should export a `meta.fixable` property."); } lintingProblems.push(problem); } } ) ); const ruleListeners = createRuleListeners(rule, 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] ); }); }); const eventGenerator = new CodePathAnalyzer(new NodeEventGenerator(emitter)); nodeQueue.forEach(traversalInfo => { currentNode = traversalInfo.node; try { if (traversalInfo.isEntering) { eventGenerator.enterNode(currentNode); } else { eventGenerator.leaveNode(currentNode); } } catch (err) { err.currentNode = currentNode; throw err; } }); return lintingProblems; } /** * Ensure the source code to be a string. * @param {string|SourceCode} textOrSourceCode The text or source code object. * @returns {string} The source code text. */ function ensureText(textOrSourceCode) { if (typeof textOrSourceCode === "object") { const { hasBOM, text } = textOrSourceCode; const bom = hasBOM ? "\uFEFF" : ""; return bom + text; } return String(textOrSourceCode); } /** * Get an environment. * @param {LinterInternalSlots} slots The internal slots of Linter. * @param {string} envId The environment ID to get. * @returns {Environment|null} The environment. */ function getEnv(slots, envId) { return ( (slots.lastConfigArray && slots.lastConfigArray.pluginEnvironments.get(envId)) || BuiltInEnvironments.get(envId) || null ); } /** * Get a rule. * @param {LinterInternalSlots} slots The internal slots of Linter. * @param {string} ruleId The rule ID to get. * @returns {Rule|null} The rule. */ function getRule(slots, ruleId) { return ( (slots.lastConfigArray && slots.lastConfigArray.pluginRules.get(ruleId)) || slots.ruleMap.get(ruleId) ); } /** * Normalize the value of the cwd * @param {string | undefined} cwd raw value of the cwd, path to a directory that should be considered as the current working directory, can be undefined. * @returns {string | undefined} normalized cwd */ function normalizeCwd(cwd) { if (cwd) { return cwd; } if (typeof process === "object") { return process.cwd(); } // It's more explicit to assign the undefined // eslint-disable-next-line no-undefined return undefined; } /** * The map to store private data. * @type {WeakMap} */ const internalSlotsMap = new WeakMap(); //------------------------------------------------------------------------------ // Public Interface //------------------------------------------------------------------------------ /** * Object that is responsible for verifying JavaScript text * @name eslint */ class Linter { /** * Initialize the Linter. * @param {Object} [config] the config object * @param {string} [config.cwd] path to a directory that should be considered as the current working directory, can be undefined. */ constructor({ cwd } = {}) { internalSlotsMap.set(this, { cwd: normalizeCwd(cwd), lastConfigArray: null, lastSourceCode: null, parserMap: new Map([["espree", espree]]), ruleMap: new Rules() }); this.version = pkg.version; } /** * Getter for package version. * @static * @returns {string} The version from package.json. */ static get version() { return pkg.version; } /** * Same as linter.verify, except without support for processors. * @param {string|SourceCode} textOrSourceCode The text to parse or a SourceCode object. * @param {ConfigData} providedConfig An ESLintConfig instance to configure everything. * @param {VerifyOptions} [providedOptions] The optional filename of the file being checked. * @returns {LintMessage[]} The results as an array of messages or an empty array if no messages. */ _verifyWithoutProcessors(textOrSourceCode, providedConfig, providedOptions) { const slots = internalSlotsMap.get(this); const config = providedConfig || {}; const options = normalizeVerifyOptions(providedOptions, config); let text; // evaluate arguments if (typeof textOrSourceCode === "string") { slots.lastSourceCode = null; text = textOrSourceCode; } else { slots.lastSourceCode = textOrSourceCode; text = textOrSourceCode.text; } // Resolve parser. let parserName = DEFAULT_PARSER_NAME; let parser = espree; if (typeof config.parser === "object" && config.parser !== null) { parserName = config.parser.filePath; parser = config.parser.definition; } else if (typeof config.parser === "string") { if (!slots.parserMap.has(config.parser)) { return [{ ruleId: null, fatal: true, severity: 2, message: `Configured parser '${config.parser}' was not found.`, line: 0, column: 0 }]; } parserName = config.parser; parser = slots.parserMap.get(config.parser); } // search and apply "eslint-env *". const envInFile = options.allowInlineConfig && !options.warnInlineConfig ? findEslintEnv(text) : {}; const resolvedEnvConfig = Object.assign({ builtin: true }, config.env, envInFile); const enabledEnvs = Object.keys(resolvedEnvConfig) .filter(envName => resolvedEnvConfig[envName]) .map(envName => getEnv(slots, envName)) .filter(env => env); const parserOptions = resolveParserOptions(parserName, config.parserOptions || {}, enabledEnvs); const configuredGlobals = resolveGlobals(config.globals || {}, enabledEnvs); const settings = config.settings || {}; if (!slots.lastSourceCode) { const parseResult = parse( text, parser, parserOptions, options.filename ); if (!parseResult.success) { return [parseResult.error]; } slots.lastSourceCode = 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). */ if (!slots.lastSourceCode.scopeManager) { slots.lastSourceCode = new SourceCode({ text: slots.lastSourceCode.text, ast: slots.lastSourceCode.ast, parserServices: slots.lastSourceCode.parserServices, visitorKeys: slots.lastSourceCode.visitorKeys, scopeManager: analyzeScope(slots.lastSourceCode.ast, parserOptions) }); } } const sourceCode = slots.lastSourceCode; const commentDirectives = options.allowInlineConfig ? getDirectiveComments(options.filename, sourceCode.ast, ruleId => getRule(slots, ruleId), options.warnInlineConfig) : { configuredRules: {}, enabledGlobals: {}, exportedVariables: {}, problems: [], disableDirectives: [] }; // augment global scope with declared global variables addDeclaredGlobals( sourceCode.scopeManager.scopes[0], configuredGlobals, { exportedVariables: commentDirectives.exportedVariables, enabledGlobals: commentDirectives.enabledGlobals } ); const configuredRules = Object.assign({}, config.rules, commentDirectives.configuredRules); let lintingProblems; try { lintingProblems = runRules( sourceCode, configuredRules, ruleId => getRule(slots, ruleId), parserOptions, parserName, settings, options.filename, options.disableFixes, slots.cwd ); } catch (err) { err.message += `\nOccurred while linting ${options.filename}`; debug("An error occurred while traversing"); debug("Filename:", options.filename); if (err.currentNode) { const { line } = err.currentNode.loc.start; debug("Line:", line); err.message += `:${line}`; } debug("Parser Options:", parserOptions); debug("Parser Path:", parserName); debug("Settings:", settings); throw err; } return applyDisableDirectives({ directives: commentDirectives.disableDirectives, problems: lintingProblems .concat(commentDirectives.problems) .sort((problemA, problemB) => problemA.line - problemB.line || problemA.column - problemB.column), reportUnusedDisableDirectives: options.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 {ConfigData|ConfigArray} config An ESLintConfig instance to configure everything. * @param {(string|(VerifyOptions&ProcessorOptions))} [filenameOrOptions] The optional filename of the file being checked. * If this is not set, the filename will default to '' in the rule context. If * an object, then it has "filename", "allowInlineConfig", and some properties. * @returns {LintMessage[]} The results as an array of messages or an empty array if no messages. */ verify(textOrSourceCode, config, filenameOrOptions) { debug("Verify"); const options = typeof filenameOrOptions === "string" ? { filename: filenameOrOptions } : filenameOrOptions || {}; // CLIEngine passes a `ConfigArray` object. if (config && typeof config.extractConfig === "function") { return this._verifyWithConfigArray(textOrSourceCode, config, options); } /* * `Linter` doesn't support `overrides` property in configuration. * So we cannot apply multiple processors. */ if (options.preprocess || options.postprocess) { return this._verifyWithProcessor(textOrSourceCode, config, options); } return this._verifyWithoutProcessors(textOrSourceCode, config, options); } /** * Verify a given code with `ConfigArray`. * @param {string|SourceCode} textOrSourceCode The source code. * @param {ConfigArray} configArray The config array. * @param {VerifyOptions&ProcessorOptions} options The options. * @returns {LintMessage[]} The found problems. */ _verifyWithConfigArray(textOrSourceCode, configArray, options) { debug("With ConfigArray: %s", options.filename); // Store the config array in order to get plugin envs and rules later. internalSlotsMap.get(this).lastConfigArray = configArray; // Extract the final config for this file. const config = configArray.extractConfig(options.filename); const processor = config.processor && configArray.pluginProcessors.get(config.processor); // Verify. if (processor) { debug("Apply the processor: %o", config.processor); const { preprocess, postprocess, supportsAutofix } = processor; const disableFixes = options.disableFixes || !supportsAutofix; return this._verifyWithProcessor( textOrSourceCode, config, { ...options, disableFixes, postprocess, preprocess }, configArray ); } return this._verifyWithoutProcessors(textOrSourceCode, config, options); } /** * Verify with a processor. * @param {string|SourceCode} textOrSourceCode The source code. * @param {ConfigData|ExtractedConfig} config The config array. * @param {VerifyOptions&ProcessorOptions} options The options. * @param {ConfigArray} [configForRecursive] The `ConfigArray` object to apply multiple processors recursively. * @returns {LintMessage[]} The found problems. */ _verifyWithProcessor(textOrSourceCode, config, options, configForRecursive) { const filename = options.filename || ""; const filenameToExpose = normalizeFilename(filename); const text = ensureText(textOrSourceCode); const preprocess = options.preprocess || (rawText => [rawText]); const postprocess = options.postprocess || lodash.flatten; const filterCodeBlock = options.filterCodeBlock || (blockFilename => blockFilename.endsWith(".js")); const originalExtname = path.extname(filename); const messageLists = preprocess(text, filenameToExpose).map((block, i) => { debug("A code block was found: %o", block.filename || "(unnamed)"); // Keep the legacy behavior. if (typeof block === "string") { return this._verifyWithoutProcessors(block, config, options); } const blockText = block.text; const blockName = path.join(filename, `${i}_${block.filename}`); // Skip this block if filtered. if (!filterCodeBlock(blockName, blockText)) { debug("This code block was skipped."); return []; } // Resolve configuration again if the file extension was changed. if (configForRecursive && path.extname(blockName) !== originalExtname) { debug("Resolving configuration again because the file extension was changed."); return this._verifyWithConfigArray( blockText, configForRecursive, { ...options, filename: blockName } ); } // Does lint. return this._verifyWithoutProcessors( blockText, config, { ...options, filename: blockName } ); }); return postprocess(messageLists, filenameToExpose); } /** * Gets the SourceCode object representing the parsed source. * @returns {SourceCode} The SourceCode object. */ getSourceCode() { return internalSlotsMap.get(this).lastSourceCode; } /** * Defines a new linting rule. * @param {string} ruleId A unique rule identifier * @param {Function | Rule} ruleModule Function from context to object mapping AST node types to event handlers * @returns {void} */ defineRule(ruleId, ruleModule) { internalSlotsMap.get(this).ruleMap.define(ruleId, ruleModule); } /** * Defines many new linting rules. * @param {Record} 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() { const { lastConfigArray, ruleMap } = internalSlotsMap.get(this); return new Map(function *() { yield* ruleMap; if (lastConfigArray) { yield* lastConfigArray.pluginRules; } }()); } /** * Define a new parser module * @param {string} parserId Name of the parser * @param {Parser} parserModule The parser object * @returns {void} */ defineParser(parserId, parserModule) { internalSlotsMap.get(this).parserMap.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 {ConfigData|ConfigArray} config The ESLint config object to use. * @param {VerifyOptions&ProcessorOptions&FixOptions} options The ESLint options object to use. * @returns {{fixed:boolean,messages:LintMessage[],output:string}} The result of the fix operation as returned from the * SourceCodeFixer. */ verifyAndFix(text, config, options) { let messages = [], fixedResult, fixed = false, passNumber = 0, currentText = text; 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(currentText, config, options); debug(`Generating fixed text for ${debugTextDescription} (pass ${passNumber})`); fixedResult = SourceCodeFixer.applyFixes(currentText, 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 currentText = 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(currentText, config, options); } // ensure the last result properly reflects if fixes were done fixedResult.fixed = fixed; fixedResult.output = currentText; return fixedResult; } } module.exports = { Linter, /** * Get the internal slots of a given Linter instance for tests. * @param {Linter} instance The Linter instance to get. * @returns {LinterInternalSlots} The internal slots. */ getLinterInternalSlots(instance) { return internalSlotsMap.get(instance); } };