2 * @fileoverview Config initialization wizard.
9 //------------------------------------------------------------------------------
11 //------------------------------------------------------------------------------
13 const util = require("util"),
14 path = require("path"),
15 enquirer = require("enquirer"),
16 ProgressBar = require("progress"),
17 semver = require("semver"),
18 espree = require("espree"),
19 recConfig = require("../../conf/eslint-recommended"),
20 ConfigOps = require("@eslint/eslintrc/lib/shared/config-ops"),
21 log = require("../shared/logging"),
22 naming = require("@eslint/eslintrc/lib/shared/naming"),
23 ModuleResolver = require("../shared/relative-module-resolver"),
24 autoconfig = require("./autoconfig.js"),
25 ConfigFile = require("./config-file"),
26 npmUtils = require("./npm-utils"),
27 { getSourceCodeOfFiles } = require("./source-code-utils");
29 const debug = require("debug")("eslint:config-initializer");
31 //------------------------------------------------------------------------------
33 //------------------------------------------------------------------------------
35 /* istanbul ignore next: hard to test fs function */
37 * Create .eslintrc file in the current working directory
38 * @param {Object} config object that contains user's answers
39 * @param {string} format The file format to write to.
42 function writeFile(config, format) {
47 if (format === "YAML") {
49 } else if (format === "JSON") {
53 const installedESLint = config.installedESLint;
55 delete config.installedESLint;
57 ConfigFile.write(config, `./.eslintrc${extname}`);
58 log.info(`Successfully created .eslintrc${extname} file in ${process.cwd()}`);
60 if (installedESLint) {
61 log.info("ESLint was installed locally. We recommend using this local copy instead of your globally-installed copy.");
66 * Get the peer dependencies of the given module.
67 * This adds the gotten value to cache at the first time, then reuses it.
68 * In a process, this function is called twice, but `npmUtils.fetchPeerDependencies` needs to access network which is relatively slow.
69 * @param {string} moduleName The module name to get.
70 * @returns {Object} The peer dependencies of the given module.
71 * This object is the object of `peerDependencies` field of `package.json`.
72 * Returns null if npm was not found.
74 function getPeerDependencies(moduleName) {
75 let result = getPeerDependencies.cache.get(moduleName);
78 log.info(`Checking peerDependencies of ${moduleName}`);
80 result = npmUtils.fetchPeerDependencies(moduleName);
81 getPeerDependencies.cache.set(moduleName, result);
86 getPeerDependencies.cache = new Map();
89 * Return necessary plugins, configs, parsers, etc. based on the config
90 * @param {Object} config config object
91 * @param {boolean} [installESLint=true] If `false` is given, it does not install eslint.
92 * @returns {string[]} An array of modules to be installed.
94 function getModulesList(config, installESLint) {
97 // Create a list of modules which should be installed based on config
99 for (const plugin of config.plugins) {
100 const moduleName = naming.normalizePackageName(plugin, "eslint-plugin");
102 modules[moduleName] = "latest";
105 if (config.extends) {
106 const extendList = Array.isArray(config.extends) ? config.extends : [config.extends];
108 for (const extend of extendList) {
109 if (extend.startsWith("eslint:") || extend.startsWith("plugin:")) {
112 const moduleName = naming.normalizePackageName(extend, "eslint-config");
114 modules[moduleName] = "latest";
117 getPeerDependencies(`${moduleName}@latest`)
122 const parser = config.parser || (config.parserOptions && config.parserOptions.parser);
125 modules[parser] = "latest";
128 if (installESLint === false) {
129 delete modules.eslint;
131 const installStatus = npmUtils.checkDevDeps(["eslint"]);
133 // Mark to show messages if it's new installation of eslint.
134 if (installStatus.eslint === false) {
135 log.info("Local ESLint installation not found.");
136 modules.eslint = modules.eslint || "latest";
137 config.installedESLint = true;
141 return Object.keys(modules).map(name => `${name}@${modules[name]}`);
145 * Set the `rules` of a config by examining a user's source code
147 * Note: This clones the config object and returns a new config to avoid mutating
148 * the original config parameter.
149 * @param {Object} answers answers received from enquirer
150 * @param {Object} config config object
151 * @returns {Object} config object with configured rules
153 function configureRules(answers, config) {
154 const BAR_TOTAL = 20,
155 BAR_SOURCE_CODE_TOTAL = 4,
156 newConfig = Object.assign({}, config),
157 disabledConfigs = {};
161 // Set up a progress bar, as this process can take a long time
162 const bar = new ProgressBar("Determining Config: :percent [:bar] :elapseds elapsed, eta :etas ", {
167 bar.tick(0); // Shows the progress bar
169 // Get the SourceCode of all chosen files
170 const patterns = answers.patterns.split(/[\s]+/u);
173 sourceCodes = getSourceCodeOfFiles(patterns, { baseConfig: newConfig, useEslintrc: false }, total => {
174 bar.tick((BAR_SOURCE_CODE_TOTAL / total));
180 const fileQty = Object.keys(sourceCodes).length;
184 throw new Error("Automatic Configuration failed. No files were able to be parsed.");
187 // Create a registry of rule configs
188 registry = new autoconfig.Registry();
189 registry.populateFromCoreRules();
191 // Lint all files with each rule config in the registry
192 registry = registry.lintSourceCode(sourceCodes, newConfig, total => {
193 bar.tick((BAR_TOTAL - BAR_SOURCE_CODE_TOTAL) / total); // Subtract out ticks used at beginning
195 debug(`\nRegistry: ${util.inspect(registry.rules, { depth: null })}`);
197 // Create a list of recommended rules, because we don't want to disable them
198 const recRules = Object.keys(recConfig.rules).filter(ruleId => ConfigOps.isErrorSeverity(recConfig.rules[ruleId]));
200 // Find and disable rules which had no error-free configuration
201 const failingRegistry = registry.getFailingRulesRegistry();
203 Object.keys(failingRegistry.rules).forEach(ruleId => {
205 // If the rule is recommended, set it to error, otherwise disable it
206 disabledConfigs[ruleId] = (recRules.indexOf(ruleId) !== -1) ? 2 : 0;
209 // Now that we know which rules to disable, strip out configs with errors
210 registry = registry.stripFailingConfigs();
213 * If there is only one config that results in no errors for a rule, we should use it.
214 * createConfig will only add rules that have one configuration in the registry.
216 const singleConfigs = registry.createConfig().rules;
219 * The "sweet spot" for number of options in a config seems to be two (severity plus one option).
220 * Very often, a third option (usually an object) is available to address
221 * edge cases, exceptions, or unique situations. We will prefer to use a config with
222 * specificity of two.
224 const specTwoConfigs = registry.filterBySpecificity(2).createConfig().rules;
226 // Maybe a specific combination using all three options works
227 const specThreeConfigs = registry.filterBySpecificity(3).createConfig().rules;
229 // If all else fails, try to use the default (severity only)
230 const defaultConfigs = registry.filterBySpecificity(1).createConfig().rules;
232 // Combine configs in reverse priority order (later take precedence)
233 newConfig.rules = Object.assign({}, disabledConfigs, defaultConfigs, specThreeConfigs, specTwoConfigs, singleConfigs);
235 // Make sure progress bar has finished (floating point rounding)
236 bar.update(BAR_TOTAL);
238 // Log out some stats to let the user know what happened
239 const finalRuleIds = Object.keys(newConfig.rules);
240 const totalRules = finalRuleIds.length;
241 const enabledRules = finalRuleIds.filter(ruleId => (newConfig.rules[ruleId] !== 0)).length;
242 const resultMessage = [
243 `\nEnabled ${enabledRules} out of ${totalRules}`,
244 `rules based on ${fileQty}`,
245 `file${(fileQty === 1) ? "." : "s."}`
248 log.info(resultMessage);
250 ConfigOps.normalizeToStrings(newConfig);
255 * process user's answers and create config object
256 * @param {Object} answers answers received from enquirer
257 * @returns {Object} config object
259 function processAnswers(answers) {
267 config.parserOptions.ecmaVersion = espree.latestEcmaVersion;
268 config.env.es2021 = true;
270 // set the module type
271 if (answers.moduleType === "esm") {
272 config.parserOptions.sourceType = "module";
273 } else if (answers.moduleType === "commonjs") {
274 config.env.commonjs = true;
277 // add in browser and node environments if necessary
278 answers.env.forEach(env => {
279 config.env[env] = true;
282 // add in library information
283 if (answers.framework === "react") {
284 config.parserOptions.ecmaFeatures = {
287 config.plugins = ["react"];
288 config.extends.push("plugin:react/recommended");
289 } else if (answers.framework === "vue") {
290 config.plugins = ["vue"];
291 config.extends.push("plugin:vue/essential");
294 if (answers.typescript) {
295 if (answers.framework === "vue") {
296 config.parserOptions.parser = "@typescript-eslint/parser";
298 config.parser = "@typescript-eslint/parser";
301 if (Array.isArray(config.plugins)) {
302 config.plugins.push("@typescript-eslint");
304 config.plugins = ["@typescript-eslint"];
308 // setup rules based on problems/style enforcement preferences
309 if (answers.purpose === "problems") {
310 config.extends.unshift("eslint:recommended");
311 } else if (answers.purpose === "style") {
312 if (answers.source === "prompt") {
313 config.extends.unshift("eslint:recommended");
314 config.rules.indent = ["error", answers.indent];
315 config.rules.quotes = ["error", answers.quotes];
316 config.rules["linebreak-style"] = ["error", answers.linebreak];
317 config.rules.semi = ["error", answers.semi ? "always" : "never"];
318 } else if (answers.source === "auto") {
319 config = configureRules(answers, config);
320 config = autoconfig.extendFromRecommended(config);
323 if (answers.typescript && config.extends.includes("eslint:recommended")) {
324 config.extends.push("plugin:@typescript-eslint/recommended");
328 if (config.extends.length === 0) {
329 delete config.extends;
330 } else if (config.extends.length === 1) {
331 config.extends = config.extends[0];
334 ConfigOps.normalizeToStrings(config);
339 * Get the version of the local ESLint.
340 * @returns {string|null} The version. If the local ESLint was not found, returns null.
342 function getLocalESLintVersion() {
344 const eslintPath = ModuleResolver.resolve("eslint", path.join(process.cwd(), "__placeholder__.js"));
345 const eslint = require(eslintPath);
347 return eslint.linter.version || null;
354 * Get the shareable config name of the chosen style guide.
355 * @param {Object} answers The answers object.
356 * @returns {string} The shareable config name.
358 function getStyleGuideName(answers) {
359 if (answers.styleguide === "airbnb" && answers.framework !== "react") {
360 return "airbnb-base";
362 return answers.styleguide;
366 * Check whether the local ESLint version conflicts with the required version of the chosen shareable config.
367 * @param {Object} answers The answers object.
368 * @returns {boolean} `true` if the local ESLint is found then it conflicts with the required version of the chosen shareable config.
370 function hasESLintVersionConflict(answers) {
372 // Get the local ESLint version.
373 const localESLintVersion = getLocalESLintVersion();
375 if (!localESLintVersion) {
379 // Get the required range of ESLint version.
380 const configName = getStyleGuideName(answers);
381 const moduleName = `eslint-config-${configName}@latest`;
382 const peerDependencies = getPeerDependencies(moduleName) || {};
383 const requiredESLintVersionRange = peerDependencies.eslint;
385 if (!requiredESLintVersionRange) {
389 answers.localESLintVersion = localESLintVersion;
390 answers.requiredESLintVersionRange = requiredESLintVersionRange;
392 // Check the version.
393 if (semver.satisfies(localESLintVersion, requiredESLintVersionRange)) {
394 answers.installESLint = false;
403 * @param {string[]} modules Modules to be installed.
406 function installModules(modules) {
407 log.info(`Installing ${modules.join(", ")}`);
408 npmUtils.installSyncSaveDev(modules);
411 /* istanbul ignore next: no need to test enquirer */
413 * Ask user to install modules.
414 * @param {string[]} modules Array of modules to be installed.
415 * @param {boolean} packageJsonExists Indicates if package.json is existed.
416 * @returns {Promise} Answer that indicates if user wants to install.
418 function askInstallModules(modules, packageJsonExists) {
420 // If no modules, do nothing.
421 if (modules.length === 0) {
422 return Promise.resolve();
425 log.info("The config that you've selected requires the following dependencies:\n");
426 log.info(modules.join(" "));
427 return enquirer.prompt([
430 name: "executeInstallation",
431 message: "Would you like to install them now with npm?",
436 return !(modules.length && packageJsonExists);
439 return this.skipped ? null : input;
442 ]).then(({ executeInstallation }) => {
443 if (executeInstallation) {
444 installModules(modules);
449 /* istanbul ignore next: no need to test enquirer */
451 * Ask use a few questions on command prompt
452 * @returns {Promise} The promise with the result of the prompt
454 function promptUser() {
456 return enquirer.prompt([
460 message: "How would you like to use ESLint?",
462 // The returned number matches the name value of nth in the choices array.
465 { message: "To check syntax only", name: "syntax" },
466 { message: "To check syntax and find problems", name: "problems" },
467 { message: "To check syntax, find problems, and enforce code style", name: "style" }
473 message: "What type of modules does your project use?",
476 { message: "JavaScript modules (import/export)", name: "esm" },
477 { message: "CommonJS (require/exports)", name: "commonjs" },
478 { message: "None of these", name: "none" }
484 message: "Which framework does your project use?",
487 { message: "React", name: "react" },
488 { message: "Vue.js", name: "vue" },
489 { message: "None of these", name: "none" }
495 message: "Does your project use TypeScript?",
503 message: "Where does your code run?",
504 hint: "(Press <space> to select, <a> to toggle all, <i> to invert selection)",
507 { message: "Browser", name: "browser" },
508 { message: "Node", name: "node" }
514 message: "How would you like to define a style for your project?",
516 { message: "Use a popular style guide", name: "guide" },
517 { message: "Answer questions about your style", name: "prompt" },
518 { message: "Inspect your JavaScript file(s)", name: "auto" }
521 return this.state.answers.purpose !== "style";
524 return this.skipped ? null : input;
530 message: "Which style guide do you want to follow?",
532 { message: "Airbnb: https://github.com/airbnb/javascript", name: "airbnb" },
533 { message: "Standard: https://github.com/standard/standard", name: "standard" },
534 { message: "Google: https://github.com/google/eslint-config-google", name: "google" }
537 this.state.answers.packageJsonExists = npmUtils.checkPackageJson();
538 return !(this.state.answers.source === "guide" && this.state.answers.packageJsonExists);
541 return this.skipped ? null : input;
547 message: "Which file(s), path(s), or glob(s) should be examined?",
549 return this.state.answers.source !== "auto";
552 if (!this.skipped && input.trim().length === 0 && input.trim() !== ",") {
553 return "You must tell us what code to examine. Try again.";
561 message: "What format do you want your config file to be in?",
563 choices: ["JavaScript", "YAML", "JSON"]
567 name: "installESLint",
569 const { answers } = this.state;
570 const verb = semver.ltr(answers.localESLintVersion, answers.requiredESLintVersionRange)
574 return `The style guide "${answers.styleguide}" requires eslint@${answers.requiredESLintVersionRange}. You are currently using eslint@${answers.localESLintVersion}.\n Do you want to ${verb}?`;
580 return !(this.state.answers.source === "guide" && this.state.answers.packageJsonExists && hasESLintVersionConflict(this.state.answers));
583 return this.skipped ? null : input;
586 ]).then(earlyAnswers => {
588 // early exit if no style guide is necessary
589 if (earlyAnswers.purpose !== "style") {
590 const config = processAnswers(earlyAnswers);
591 const modules = getModulesList(config);
593 return askInstallModules(modules, earlyAnswers.packageJsonExists)
594 .then(() => writeFile(config, earlyAnswers.format));
597 // early exit if you are using a style guide
598 if (earlyAnswers.source === "guide") {
599 if (!earlyAnswers.packageJsonExists) {
600 log.info("A package.json is necessary to install plugins such as style guides. Run `npm init` to create a package.json file and try again.");
603 if (earlyAnswers.installESLint === false && !semver.satisfies(earlyAnswers.localESLintVersion, earlyAnswers.requiredESLintVersionRange)) {
604 log.info(`Note: it might not work since ESLint's version is mismatched with the ${earlyAnswers.styleguide} config.`);
606 if (earlyAnswers.styleguide === "airbnb" && earlyAnswers.framework !== "react") {
607 earlyAnswers.styleguide = "airbnb-base";
610 const config = processAnswers(earlyAnswers);
612 if (Array.isArray(config.extends)) {
613 config.extends.push(earlyAnswers.styleguide);
614 } else if (config.extends) {
615 config.extends = [config.extends, earlyAnswers.styleguide];
617 config.extends = [earlyAnswers.styleguide];
620 const modules = getModulesList(config);
622 return askInstallModules(modules, earlyAnswers.packageJsonExists)
623 .then(() => writeFile(config, earlyAnswers.format));
627 if (earlyAnswers.source === "auto") {
628 const combinedAnswers = Object.assign({}, earlyAnswers);
629 const config = processAnswers(combinedAnswers);
630 const modules = getModulesList(config);
632 return askInstallModules(modules).then(() => writeFile(config, earlyAnswers.format));
635 // continue with the style questions otherwise...
636 return enquirer.prompt([
640 message: "What style of indentation do you use?",
642 choices: [{ message: "Tabs", name: "tab" }, { message: "Spaces", name: 4 }]
647 message: "What quotes do you use for strings?",
649 choices: [{ message: "Double", name: "double" }, { message: "Single", name: "single" }]
654 message: "What line endings do you use?",
656 choices: [{ message: "Unix", name: "unix" }, { message: "Windows", name: "windows" }]
661 message: "Do you require semicolons?",
667 const totalAnswers = Object.assign({}, earlyAnswers, answers);
669 const config = processAnswers(totalAnswers);
670 const modules = getModulesList(config);
672 return askInstallModules(modules).then(() => writeFile(config, earlyAnswers.format));
677 //------------------------------------------------------------------------------
679 //------------------------------------------------------------------------------
683 hasESLintVersionConflict,
686 /* istanbul ignore next */initializeConfig() {
691 module.exports = init;