eslint/lib/init/config-initializer.js

   1 /**
   2  * @fileoverview Config initialization wizard.
   3  * @author Ilya Volodin
   4  */
   5
   6
   7 "use strict";
   8
   9 //------------------------------------------------------------------------------
  10 // Requirements
  11 //------------------------------------------------------------------------------
  12
  13 const util = require("util"),
  14     path = require("path"),
  15     inquirer = require("inquirer"),
  16     ProgressBar = require("progress"),
  17     semver = require("semver"),
  18     espree = require("espree"),
  19     recConfig = require("../../conf/eslint-recommended"),
  20     ConfigOps = require("../shared/config-ops"),
  21     log = require("../shared/logging"),
  22     naming = require("../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");
  28
  29 const debug = require("debug")("eslint:config-initializer");
  30
  31 //------------------------------------------------------------------------------
  32 // Private
  33 //------------------------------------------------------------------------------
  34
  35 /* istanbul ignore next: hard to test fs function */
  36 /**
  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.
  40  * @returns {void}
  41  */
  42 function writeFile(config, format) {
  43
  44     // default is .js
  45     let extname = ".js";
  46
  47     if (format === "YAML") {
  48         extname = ".yml";
  49     } else if (format === "JSON") {
  50         extname = ".json";
  51     }
  52
  53     const installedESLint = config.installedESLint;
  54
  55     delete config.installedESLint;
  56
  57     ConfigFile.write(config, `./.eslintrc${extname}`);
  58     log.info(`Successfully created .eslintrc${extname} file in ${process.cwd()}`);
  59
  60     if (installedESLint) {
  61         log.info("ESLint was installed locally. We recommend using this local copy instead of your globally-installed copy.");
  62     }
  63 }
  64
  65 /**
  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.
  73  */
  74 function getPeerDependencies(moduleName) {
  75     let result = getPeerDependencies.cache.get(moduleName);
  76
  77     if (!result) {
  78         log.info(`Checking peerDependencies of ${moduleName}`);
  79
  80         result = npmUtils.fetchPeerDependencies(moduleName);
  81         getPeerDependencies.cache.set(moduleName, result);
  82     }
  83
  84     return result;
  85 }
  86 getPeerDependencies.cache = new Map();
  87
  88 /**
  89  * Return necessary plugins, configs, parsers, etc. based on the config
  90  * @param   {Object} config  config object
  91  * @param   {boolean} [installESLint=true]  If `false` is given, it does not install eslint.
  92  * @returns {string[]} An array of modules to be installed.
  93  */
  94 function getModulesList(config, installESLint) {
  95     const modules = {};
  96
  97     // Create a list of modules which should be installed based on config
  98     if (config.plugins) {
  99         for (const plugin of config.plugins) {
 100             const moduleName = naming.normalizePackageName(plugin, "eslint-plugin");
 101
 102             modules[moduleName] = "latest";
 103         }
 104     }
 105     if (config.extends) {
 106         const extendList = Array.isArray(config.extends) ? config.extends : [config.extends];
 107
 108         for (const extend of extendList) {
 109             if (extend.startsWith("eslint:") || extend.startsWith("plugin:")) {
 110                 continue;
 111             }
 112             const moduleName = naming.normalizePackageName(extend, "eslint-config");
 113
 114             modules[moduleName] = "latest";
 115             Object.assign(
 116                 modules,
 117                 getPeerDependencies(`${moduleName}@latest`)
 118             );
 119         }
 120     }
 121
 122     const parser = config.parser || (config.parserOptions && config.parserOptions.parser);
 123
 124     if (parser) {
 125         modules[parser] = "latest";
 126     }
 127
 128     if (installESLint === false) {
 129         delete modules.eslint;
 130     } else {
 131         const installStatus = npmUtils.checkDevDeps(["eslint"]);
 132
 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;
 138         }
 139     }
 140
 141     return Object.keys(modules).map(name => `${name}@${modules[name]}`);
 142 }
 143
 144 /**
 145  * Set the `rules` of a config by examining a user's source code
 146  *
 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 inquirer
 150  * @param   {Object} config   config object
 151  * @returns {Object}          config object with configured rules
 152  */
 153 function configureRules(answers, config) {
 154     const BAR_TOTAL = 20,
 155         BAR_SOURCE_CODE_TOTAL = 4,
 156         newConfig = Object.assign({}, config),
 157         disabledConfigs = {};
 158     let sourceCodes,
 159         registry;
 160
 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 ", {
 163         width: 30,
 164         total: BAR_TOTAL
 165     });
 166
 167     bar.tick(0); // Shows the progress bar
 168
 169     // Get the SourceCode of all chosen files
 170     const patterns = answers.patterns.split(/[\s]+/u);
 171
 172     try {
 173         sourceCodes = getSourceCodeOfFiles(patterns, { baseConfig: newConfig, useEslintrc: false }, total => {
 174             bar.tick((BAR_SOURCE_CODE_TOTAL / total));
 175         });
 176     } catch (e) {
 177         log.info("\n");
 178         throw e;
 179     }
 180     const fileQty = Object.keys(sourceCodes).length;
 181
 182     if (fileQty === 0) {
 183         log.info("\n");
 184         throw new Error("Automatic Configuration failed.  No files were able to be parsed.");
 185     }
 186
 187     // Create a registry of rule configs
 188     registry = new autoconfig.Registry();
 189     registry.populateFromCoreRules();
 190
 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
 194     });
 195     debug(`\nRegistry: ${util.inspect(registry.rules, { depth: null })}`);
 196
 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]));
 199
 200     // Find and disable rules which had no error-free configuration
 201     const failingRegistry = registry.getFailingRulesRegistry();
 202
 203     Object.keys(failingRegistry.rules).forEach(ruleId => {
 204
 205         // If the rule is recommended, set it to error, otherwise disable it
 206         disabledConfigs[ruleId] = (recRules.indexOf(ruleId) !== -1) ? 2 : 0;
 207     });
 208
 209     // Now that we know which rules to disable, strip out configs with errors
 210     registry = registry.stripFailingConfigs();
 211
 212     /*
 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.
 215      */
 216     const singleConfigs = registry.createConfig().rules;
 217
 218     /*
 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.
 223      */
 224     const specTwoConfigs = registry.filterBySpecificity(2).createConfig().rules;
 225
 226     // Maybe a specific combination using all three options works
 227     const specThreeConfigs = registry.filterBySpecificity(3).createConfig().rules;
 228
 229     // If all else fails, try to use the default (severity only)
 230     const defaultConfigs = registry.filterBySpecificity(1).createConfig().rules;
 231
 232     // Combine configs in reverse priority order (later take precedence)
 233     newConfig.rules = Object.assign({}, disabledConfigs, defaultConfigs, specThreeConfigs, specTwoConfigs, singleConfigs);
 234
 235     // Make sure progress bar has finished (floating point rounding)
 236     bar.update(BAR_TOTAL);
 237
 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."}`
 246     ].join(" ");
 247
 248     log.info(resultMessage);
 249
 250     ConfigOps.normalizeToStrings(newConfig);
 251     return newConfig;
 252 }
 253
 254 /**
 255  * process user's answers and create config object
 256  * @param {Object} answers answers received from inquirer
 257  * @returns {Object} config object
 258  */
 259 function processAnswers(answers) {
 260     let config = {
 261         rules: {},
 262         env: {},
 263         parserOptions: {},
 264         extends: []
 265     };
 266
 267     config.parserOptions.ecmaVersion = espree.latestEcmaVersion;
 268     config.env.es2020 = true;
 269
 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;
 275     }
 276
 277     // add in browser and node environments if necessary
 278     answers.env.forEach(env => {
 279         config.env[env] = true;
 280     });
 281
 282     // add in library information
 283     if (answers.framework === "react") {
 284         config.parserOptions.ecmaFeatures = {
 285             jsx: true
 286         };
 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");
 292     }
 293
 294     if (answers.typescript) {
 295         if (answers.framework === "vue") {
 296             config.parserOptions.parser = "@typescript-eslint/parser";
 297         } else {
 298             config.parser = "@typescript-eslint/parser";
 299         }
 300
 301         if (Array.isArray(config.plugins)) {
 302             config.plugins.push("@typescript-eslint");
 303         } else {
 304             config.plugins = ["@typescript-eslint"];
 305         }
 306     }
 307
 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);
 321         }
 322     }
 323     if (answers.typescript && config.extends.includes("eslint:recommended")) {
 324         config.extends.push("plugin:@typescript-eslint/eslint-recommended");
 325         config.extends.push("plugin:@typescript-eslint/recommended");
 326     }
 327
 328     // normalize extends
 329     if (config.extends.length === 0) {
 330         delete config.extends;
 331     } else if (config.extends.length === 1) {
 332         config.extends = config.extends[0];
 333     }
 334
 335     ConfigOps.normalizeToStrings(config);
 336     return config;
 337 }
 338
 339 /**
 340  * Get the version of the local ESLint.
 341  * @returns {string|null} The version. If the local ESLint was not found, returns null.
 342  */
 343 function getLocalESLintVersion() {
 344     try {
 345         const eslintPath = ModuleResolver.resolve("eslint", path.join(process.cwd(), "__placeholder__.js"));
 346         const eslint = require(eslintPath);
 347
 348         return eslint.linter.version || null;
 349     } catch {
 350         return null;
 351     }
 352 }
 353
 354 /**
 355  * Get the shareable config name of the chosen style guide.
 356  * @param {Object} answers The answers object.
 357  * @returns {string} The shareable config name.
 358  */
 359 function getStyleGuideName(answers) {
 360     if (answers.styleguide === "airbnb" && answers.framework !== "react") {
 361         return "airbnb-base";
 362     }
 363     return answers.styleguide;
 364 }
 365
 366 /**
 367  * Check whether the local ESLint version conflicts with the required version of the chosen shareable config.
 368  * @param {Object} answers The answers object.
 369  * @returns {boolean} `true` if the local ESLint is found then it conflicts with the required version of the chosen shareable config.
 370  */
 371 function hasESLintVersionConflict(answers) {
 372
 373     // Get the local ESLint version.
 374     const localESLintVersion = getLocalESLintVersion();
 375
 376     if (!localESLintVersion) {
 377         return false;
 378     }
 379
 380     // Get the required range of ESLint version.
 381     const configName = getStyleGuideName(answers);
 382     const moduleName = `eslint-config-${configName}@latest`;
 383     const peerDependencies = getPeerDependencies(moduleName) || {};
 384     const requiredESLintVersionRange = peerDependencies.eslint;
 385
 386     if (!requiredESLintVersionRange) {
 387         return false;
 388     }
 389
 390     answers.localESLintVersion = localESLintVersion;
 391     answers.requiredESLintVersionRange = requiredESLintVersionRange;
 392
 393     // Check the version.
 394     if (semver.satisfies(localESLintVersion, requiredESLintVersionRange)) {
 395         answers.installESLint = false;
 396         return false;
 397     }
 398
 399     return true;
 400 }
 401
 402 /**
 403  * Install modules.
 404  * @param   {string[]} modules Modules to be installed.
 405  * @returns {void}
 406  */
 407 function installModules(modules) {
 408     log.info(`Installing ${modules.join(", ")}`);
 409     npmUtils.installSyncSaveDev(modules);
 410 }
 411
 412 /* istanbul ignore next: no need to test inquirer */
 413 /**
 414  * Ask user to install modules.
 415  * @param   {string[]} modules Array of modules to be installed.
 416  * @param   {boolean} packageJsonExists Indicates if package.json is existed.
 417  * @returns {Promise} Answer that indicates if user wants to install.
 418  */
 419 function askInstallModules(modules, packageJsonExists) {
 420
 421     // If no modules, do nothing.
 422     if (modules.length === 0) {
 423         return Promise.resolve();
 424     }
 425
 426     log.info("The config that you've selected requires the following dependencies:\n");
 427     log.info(modules.join(" "));
 428     return inquirer.prompt([
 429         {
 430             type: "confirm",
 431             name: "executeInstallation",
 432             message: "Would you like to install them now with npm?",
 433             default: true,
 434             when() {
 435                 return modules.length && packageJsonExists;
 436             }
 437         }
 438     ]).then(({ executeInstallation }) => {
 439         if (executeInstallation) {
 440             installModules(modules);
 441         }
 442     });
 443 }
 444
 445 /* istanbul ignore next: no need to test inquirer */
 446 /**
 447  * Ask use a few questions on command prompt
 448  * @returns {Promise} The promise with the result of the prompt
 449  */
 450 function promptUser() {
 451
 452     return inquirer.prompt([
 453         {
 454             type: "list",
 455             name: "purpose",
 456             message: "How would you like to use ESLint?",
 457             default: "problems",
 458             choices: [
 459                 { name: "To check syntax only", value: "syntax" },
 460                 { name: "To check syntax and find problems", value: "problems" },
 461                 { name: "To check syntax, find problems, and enforce code style", value: "style" }
 462             ]
 463         },
 464         {
 465             type: "list",
 466             name: "moduleType",
 467             message: "What type of modules does your project use?",
 468             default: "esm",
 469             choices: [
 470                 { name: "JavaScript modules (import/export)", value: "esm" },
 471                 { name: "CommonJS (require/exports)", value: "commonjs" },
 472                 { name: "None of these", value: "none" }
 473             ]
 474         },
 475         {
 476             type: "list",
 477             name: "framework",
 478             message: "Which framework does your project use?",
 479             default: "react",
 480             choices: [
 481                 { name: "React", value: "react" },
 482                 { name: "Vue.js", value: "vue" },
 483                 { name: "None of these", value: "none" }
 484             ]
 485         },
 486         {
 487             type: "confirm",
 488             name: "typescript",
 489             message: "Does your project use TypeScript?",
 490             default: false
 491         },
 492         {
 493             type: "checkbox",
 494             name: "env",
 495             message: "Where does your code run?",
 496             default: ["browser"],
 497             choices: [
 498                 { name: "Browser", value: "browser" },
 499                 { name: "Node", value: "node" }
 500             ]
 501         },
 502         {
 503             type: "list",
 504             name: "source",
 505             message: "How would you like to define a style for your project?",
 506             default: "guide",
 507             choices: [
 508                 { name: "Use a popular style guide", value: "guide" },
 509                 { name: "Answer questions about your style", value: "prompt" },
 510                 { name: "Inspect your JavaScript file(s)", value: "auto" }
 511             ],
 512             when(answers) {
 513                 return answers.purpose === "style";
 514             }
 515         },
 516         {
 517             type: "list",
 518             name: "styleguide",
 519             message: "Which style guide do you want to follow?",
 520             choices: [
 521                 { name: "Airbnb: https://github.com/airbnb/javascript", value: "airbnb" },
 522                 { name: "Standard: https://github.com/standard/standard", value: "standard" },
 523                 { name: "Google: https://github.com/google/eslint-config-google", value: "google" }
 524             ],
 525             when(answers) {
 526                 answers.packageJsonExists = npmUtils.checkPackageJson();
 527                 return answers.source === "guide" && answers.packageJsonExists;
 528             }
 529         },
 530         {
 531             type: "input",
 532             name: "patterns",
 533             message: "Which file(s), path(s), or glob(s) should be examined?",
 534             when(answers) {
 535                 return (answers.source === "auto");
 536             },
 537             validate(input) {
 538                 if (input.trim().length === 0 && input.trim() !== ",") {
 539                     return "You must tell us what code to examine. Try again.";
 540                 }
 541                 return true;
 542             }
 543         },
 544         {
 545             type: "list",
 546             name: "format",
 547             message: "What format do you want your config file to be in?",
 548             default: "JavaScript",
 549             choices: ["JavaScript", "YAML", "JSON"]
 550         },
 551         {
 552             type: "confirm",
 553             name: "installESLint",
 554             message(answers) {
 555                 const verb = semver.ltr(answers.localESLintVersion, answers.requiredESLintVersionRange)
 556                     ? "upgrade"
 557                     : "downgrade";
 558
 559                 return `The style guide "${answers.styleguide}" requires eslint@${answers.requiredESLintVersionRange}. You are currently using eslint@${answers.localESLintVersion}.\n  Do you want to ${verb}?`;
 560             },
 561             default: true,
 562             when(answers) {
 563                 return answers.source === "guide" && answers.packageJsonExists && hasESLintVersionConflict(answers);
 564             }
 565         }
 566     ]).then(earlyAnswers => {
 567
 568         // early exit if no style guide is necessary
 569         if (earlyAnswers.purpose !== "style") {
 570             const config = processAnswers(earlyAnswers);
 571             const modules = getModulesList(config);
 572
 573             return askInstallModules(modules, earlyAnswers.packageJsonExists)
 574                 .then(() => writeFile(config, earlyAnswers.format));
 575         }
 576
 577         // early exit if you are using a style guide
 578         if (earlyAnswers.source === "guide") {
 579             if (!earlyAnswers.packageJsonExists) {
 580                 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.");
 581                 return void 0;
 582             }
 583             if (earlyAnswers.installESLint === false && !semver.satisfies(earlyAnswers.localESLintVersion, earlyAnswers.requiredESLintVersionRange)) {
 584                 log.info(`Note: it might not work since ESLint's version is mismatched with the ${earlyAnswers.styleguide} config.`);
 585             }
 586             if (earlyAnswers.styleguide === "airbnb" && earlyAnswers.framework !== "react") {
 587                 earlyAnswers.styleguide = "airbnb-base";
 588             }
 589
 590             const config = processAnswers(earlyAnswers);
 591
 592             if (Array.isArray(config.extends)) {
 593                 config.extends.push(earlyAnswers.styleguide);
 594             } else if (config.extends) {
 595                 config.extends = [config.extends, earlyAnswers.styleguide];
 596             } else {
 597                 config.extends = [earlyAnswers.styleguide];
 598             }
 599
 600             const modules = getModulesList(config);
 601
 602             return askInstallModules(modules, earlyAnswers.packageJsonExists)
 603                 .then(() => writeFile(config, earlyAnswers.format));
 604
 605         }
 606
 607         if (earlyAnswers.source === "auto") {
 608             const combinedAnswers = Object.assign({}, earlyAnswers);
 609             const config = processAnswers(combinedAnswers);
 610             const modules = getModulesList(config);
 611
 612             return askInstallModules(modules).then(() => writeFile(config, earlyAnswers.format));
 613         }
 614
 615         // continue with the style questions otherwise...
 616         return inquirer.prompt([
 617             {
 618                 type: "list",
 619                 name: "indent",
 620                 message: "What style of indentation do you use?",
 621                 default: "tab",
 622                 choices: [{ name: "Tabs", value: "tab" }, { name: "Spaces", value: 4 }]
 623             },
 624             {
 625                 type: "list",
 626                 name: "quotes",
 627                 message: "What quotes do you use for strings?",
 628                 default: "double",
 629                 choices: [{ name: "Double", value: "double" }, { name: "Single", value: "single" }]
 630             },
 631             {
 632                 type: "list",
 633                 name: "linebreak",
 634                 message: "What line endings do you use?",
 635                 default: "unix",
 636                 choices: [{ name: "Unix", value: "unix" }, { name: "Windows", value: "windows" }]
 637             },
 638             {
 639                 type: "confirm",
 640                 name: "semi",
 641                 message: "Do you require semicolons?",
 642                 default: true
 643             }
 644         ]).then(answers => {
 645             const totalAnswers = Object.assign({}, earlyAnswers, answers);
 646
 647             const config = processAnswers(totalAnswers);
 648             const modules = getModulesList(config);
 649
 650             return askInstallModules(modules).then(() => writeFile(config, earlyAnswers.format));
 651         });
 652     });
 653 }
 654
 655 //------------------------------------------------------------------------------
 656 // Public Interface
 657 //------------------------------------------------------------------------------
 658
 659 const init = {
 660     getModulesList,
 661     hasESLintVersionConflict,
 662     installModules,
 663     processAnswers,
 664     /* istanbul ignore next */initializeConfig() {
 665         return promptUser();
 666     }
 667 };
 668
 669 module.exports = init;