/**
* @fileoverview Config initialization wizard.
* @author Ilya Volodin
*/
"use strict";
//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------
const util = require("util"),
inquirer = require("inquirer"),
ProgressBar = require("progress"),
semver = require("semver"),
autoconfig = require("./autoconfig.js"),
ConfigFile = require("./config-file"),
ConfigOps = require("./config-ops"),
getSourceCodeOfFiles = require("../util/source-code-util").getSourceCodeOfFiles,
ModuleResolver = require("../util/module-resolver"),
npmUtil = require("../util/npm-util"),
recConfig = require("../../conf/eslint-recommended"),
log = require("../logging");
const debug = require("debug")("eslint:config-initializer");
//------------------------------------------------------------------------------
// Private
//------------------------------------------------------------------------------
/* istanbul ignore next: hard to test fs function */
/**
* Create .eslintrc file in the current working directory
* @param {Object} config object that contains user's answers
* @param {string} format The file format to write to.
* @returns {void}
*/
function writeFile(config, format) {
// default is .js
let extname = ".js";
if (format === "YAML") {
extname = ".yml";
} else if (format === "JSON") {
extname = ".json";
}
const installedESLint = config.installedESLint;
delete config.installedESLint;
ConfigFile.write(config, `./.eslintrc${extname}`);
log.info(`Successfully created .eslintrc${extname} file in ${process.cwd()}`);
if (installedESLint) {
log.info("ESLint was installed locally. We recommend using this local copy instead of your globally-installed copy.");
}
}
/**
* Get the peer dependencies of the given module.
* This adds the gotten value to cache at the first time, then reuses it.
* In a process, this function is called twice, but `npmUtil.fetchPeerDependencies` needs to access network which is relatively slow.
* @param {string} moduleName The module name to get.
* @returns {Object} The peer dependencies of the given module.
* This object is the object of `peerDependencies` field of `package.json`.
* Returns null if npm was not found.
*/
function getPeerDependencies(moduleName) {
let result = getPeerDependencies.cache.get(moduleName);
if (!result) {
log.info(`Checking peerDependencies of ${moduleName}`);
result = npmUtil.fetchPeerDependencies(moduleName);
getPeerDependencies.cache.set(moduleName, result);
}
return result;
}
getPeerDependencies.cache = new Map();
/**
* Synchronously install necessary plugins, configs, parsers, etc. based on the config
* @param {Object} config config object
* @param {boolean} [installESLint=true] If `false` is given, it does not install eslint.
* @returns {void}
*/
function installModules(config, installESLint) {
const modules = {};
// Create a list of modules which should be installed based on config
if (config.plugins) {
for (const plugin of config.plugins) {
modules[`eslint-plugin-${plugin}`] = "latest";
}
}
if (config.extends && config.extends.indexOf("eslint:") === -1) {
const moduleName = `eslint-config-${config.extends}`;
modules[moduleName] = "latest";
Object.assign(
modules,
getPeerDependencies(`${moduleName}@latest`)
);
}
// If no modules, do nothing.
if (Object.keys(modules).length === 0) {
return;
}
if (installESLint === false) {
delete modules.eslint;
} else {
const installStatus = npmUtil.checkDevDeps(["eslint"]);
// Mark to show messages if it's new installation of eslint.
if (installStatus.eslint === false) {
log.info("Local ESLint installation not found.");
modules.eslint = modules.eslint || "latest";
config.installedESLint = true;
}
}
// Install packages
const modulesToInstall = Object.keys(modules).map(name => `${name}@${modules[name]}`);
log.info(`Installing ${modulesToInstall.join(", ")}`);
npmUtil.installSyncSaveDev(modulesToInstall);
}
/**
* Set the `rules` of a config by examining a user's source code
*
* Note: This clones the config object and returns a new config to avoid mutating
* the original config parameter.
*
* @param {Object} answers answers received from inquirer
* @param {Object} config config object
* @returns {Object} config object with configured rules
*/
function configureRules(answers, config) {
const BAR_TOTAL = 20,
BAR_SOURCE_CODE_TOTAL = 4,
newConfig = Object.assign({}, config),
disabledConfigs = {};
let sourceCodes,
registry;
// Set up a progress bar, as this process can take a long time
const bar = new ProgressBar("Determining Config: :percent [:bar] :elapseds elapsed, eta :etas ", {
width: 30,
total: BAR_TOTAL
});
bar.tick(0); // Shows the progress bar
// Get the SourceCode of all chosen files
const patterns = answers.patterns.split(/[\s]+/);
try {
sourceCodes = getSourceCodeOfFiles(patterns, { baseConfig: newConfig, useEslintrc: false }, total => {
bar.tick((BAR_SOURCE_CODE_TOTAL / total));
});
} catch (e) {
log.info("\n");
throw e;
}
const fileQty = Object.keys(sourceCodes).length;
if (fileQty === 0) {
log.info("\n");
throw new Error("Automatic Configuration failed. No files were able to be parsed.");
}
// Create a registry of rule configs
registry = new autoconfig.Registry();
registry.populateFromCoreRules();
// Lint all files with each rule config in the registry
registry = registry.lintSourceCode(sourceCodes, newConfig, total => {
bar.tick((BAR_TOTAL - BAR_SOURCE_CODE_TOTAL) / total); // Subtract out ticks used at beginning
});
debug(`\nRegistry: ${util.inspect(registry.rules, { depth: null })}`);
// Create a list of recommended rules, because we don't want to disable them
const recRules = Object.keys(recConfig.rules).filter(ruleId => ConfigOps.isErrorSeverity(recConfig.rules[ruleId]));
// Find and disable rules which had no error-free configuration
const failingRegistry = registry.getFailingRulesRegistry();
Object.keys(failingRegistry.rules).forEach(ruleId => {
// If the rule is recommended, set it to error, otherwise disable it
disabledConfigs[ruleId] = (recRules.indexOf(ruleId) !== -1) ? 2 : 0;
});
// Now that we know which rules to disable, strip out configs with errors
registry = registry.stripFailingConfigs();
/*
* If there is only one config that results in no errors for a rule, we should use it.
* createConfig will only add rules that have one configuration in the registry.
*/
const singleConfigs = registry.createConfig().rules;
/*
* The "sweet spot" for number of options in a config seems to be two (severity plus one option).
* Very often, a third option (usually an object) is available to address
* edge cases, exceptions, or unique situations. We will prefer to use a config with
* specificity of two.
*/
const specTwoConfigs = registry.filterBySpecificity(2).createConfig().rules;
// Maybe a specific combination using all three options works
const specThreeConfigs = registry.filterBySpecificity(3).createConfig().rules;
// If all else fails, try to use the default (severity only)
const defaultConfigs = registry.filterBySpecificity(1).createConfig().rules;
// Combine configs in reverse priority order (later take precedence)
newConfig.rules = Object.assign({}, disabledConfigs, defaultConfigs, specThreeConfigs, specTwoConfigs, singleConfigs);
// Make sure progress bar has finished (floating point rounding)
bar.update(BAR_TOTAL);
// Log out some stats to let the user know what happened
const finalRuleIds = Object.keys(newConfig.rules);
const totalRules = finalRuleIds.length;
const enabledRules = finalRuleIds.filter(ruleId => (newConfig.rules[ruleId] !== 0)).length;
const resultMessage = [
`\nEnabled ${enabledRules} out of ${totalRules}`,
`rules based on ${fileQty}`,
`file${(fileQty === 1) ? "." : "s."}`
].join(" ");
log.info(resultMessage);
ConfigOps.normalizeToStrings(newConfig);
return newConfig;
}
/**
* process user's answers and create config object
* @param {Object} answers answers received from inquirer
* @returns {Object} config object
*/
function processAnswers(answers) {
let config = { rules: {}, env: {} };
if (answers.es6) {
config.env.es6 = true;
if (answers.modules) {
config.parserOptions = config.parserOptions || {};
config.parserOptions.sourceType = "module";
}
}
if (answers.commonjs) {
config.env.commonjs = true;
}
answers.env.forEach(env => {
config.env[env] = true;
});
if (answers.jsx) {
config.parserOptions = config.parserOptions || {};
config.parserOptions.ecmaFeatures = config.parserOptions.ecmaFeatures || {};
config.parserOptions.ecmaFeatures.jsx = true;
if (answers.react) {
config.plugins = ["react"];
config.parserOptions.ecmaFeatures.experimentalObjectRestSpread = true;
}
}
if (answers.source === "prompt") {
config.extends = "eslint:recommended";
config.rules.indent = ["error", answers.indent];
config.rules.quotes = ["error", answers.quotes];
config.rules["linebreak-style"] = ["error", answers.linebreak];
config.rules.semi = ["error", answers.semi ? "always" : "never"];
}
installModules(config);
if (answers.source === "auto") {
config = configureRules(answers, config);
config = autoconfig.extendFromRecommended(config);
}
ConfigOps.normalizeToStrings(config);
return config;
}
/**
* process user's style guide of choice and return an appropriate config object.
* @param {string} guide name of the chosen style guide
* @param {boolean} [installESLint=true] If `false` is given, it does not install eslint.
* @returns {Object} config object
*/
function getConfigForStyleGuide(guide, installESLint) {
const guides = {
google: { extends: "google" },
airbnb: { extends: "airbnb" },
"airbnb-base": { extends: "airbnb-base" },
standard: { extends: "standard" }
};
if (!guides[guide]) {
throw new Error("You referenced an unsupported guide.");
}
installModules(guides[guide], installESLint);
return guides[guide];
}
/**
* Get the version of the local ESLint.
* @returns {string|null} The version. If the local ESLint was not found, returns null.
*/
function getLocalESLintVersion() {
try {
const resolver = new ModuleResolver();
const eslintPath = resolver.resolve("eslint", process.cwd());
const eslint = require(eslintPath);
return eslint.linter.version || null;
} catch (_err) {
return null;
}
}
/**
* Get the shareable config name of the chosen style guide.
* @param {Object} answers The answers object.
* @returns {string} The shareable config name.
*/
function getStyleGuideName(answers) {
if (answers.styleguide === "airbnb" && !answers.airbnbReact) {
return "airbnb-base";
}
return answers.styleguide;
}
/**
* Check whether the local ESLint version conflicts with the required version of the chosen shareable config.
* @param {Object} answers The answers object.
* @returns {boolean} `true` if the local ESLint is found then it conflicts with the required version of the chosen shareable config.
*/
function hasESLintVersionConflict(answers) {
// Get the local ESLint version.
const localESLintVersion = getLocalESLintVersion();
if (!localESLintVersion) {
return false;
}
// Get the required range of ESLint version.
const configName = getStyleGuideName(answers);
const moduleName = `eslint-config-${configName}@latest`;
const peerDependencies = getPeerDependencies(moduleName) || {};
const requiredESLintVersionRange = peerDependencies.eslint;
if (!requiredESLintVersionRange) {
return false;
}
answers.localESLintVersion = localESLintVersion;
answers.requiredESLintVersionRange = requiredESLintVersionRange;
// Check the version.
if (semver.satisfies(localESLintVersion, requiredESLintVersionRange)) {
answers.installESLint = false;
return false;
}
return true;
}
/* istanbul ignore next: no need to test inquirer*/
/**
* Ask use a few questions on command prompt
* @returns {Promise} The promise with the result of the prompt
*/
function promptUser() {
return inquirer.prompt([
{
type: "list",
name: "source",
message: "How would you like to configure ESLint?",
default: "prompt",
choices: [
{ name: "Answer questions about your style", value: "prompt" },
{ name: "Use a popular style guide", value: "guide" },
{ name: "Inspect your JavaScript file(s)", value: "auto" }
]
},
{
type: "list",
name: "styleguide",
message: "Which style guide do you want to follow?",
choices: [{ name: "Google", value: "google" }, { name: "Airbnb", value: "airbnb" }, { name: "Standard", value: "standard" }],
when(answers) {
answers.packageJsonExists = npmUtil.checkPackageJson();
return answers.source === "guide" && answers.packageJsonExists;
}
},
{
type: "confirm",
name: "airbnbReact",
message: "Do you use React?",
default: false,
when(answers) {
return answers.styleguide === "airbnb";
}
},
{
type: "input",
name: "patterns",
message: "Which file(s), path(s), or glob(s) should be examined?",
when(answers) {
return (answers.source === "auto");
},
validate(input) {
if (input.trim().length === 0 && input.trim() !== ",") {
return "You must tell us what code to examine. Try again.";
}
return true;
}
},
{
type: "list",
name: "format",
message: "What format do you want your config file to be in?",
default: "JavaScript",
choices: ["JavaScript", "YAML", "JSON"],
when(answers) {
return ((answers.source === "guide" && answers.packageJsonExists) || answers.source === "auto");
}
},
{
type: "confirm",
name: "installESLint",
message(answers) {
const verb = semver.ltr(answers.localESLintVersion, answers.requiredESLintVersionRange)
? "upgrade"
: "downgrade";
return `The style guide "${answers.styleguide}" requires eslint@${answers.requiredESLintVersionRange}. You are currently using eslint@${answers.localESLintVersion}.\n Do you want to ${verb}?`;
},
default: true,
when(answers) {
return answers.source === "guide" && answers.packageJsonExists && hasESLintVersionConflict(answers);
}
}
]).then(earlyAnswers => {
// early exit if you are using a style guide
if (earlyAnswers.source === "guide") {
if (!earlyAnswers.packageJsonExists) {
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.");
return void 0;
}
if (earlyAnswers.installESLint === false && !semver.satisfies(earlyAnswers.localESLintVersion, earlyAnswers.requiredESLintVersionRange)) {
log.info(`Note: it might not work since ESLint's version is mismatched with the ${earlyAnswers.styleguide} config.`);
}
if (earlyAnswers.styleguide === "airbnb" && !earlyAnswers.airbnbReact) {
earlyAnswers.styleguide = "airbnb-base";
}
const config = getConfigForStyleGuide(earlyAnswers.styleguide, earlyAnswers.installESLint);
writeFile(config, earlyAnswers.format);
return void 0;
}
// continue with the questions otherwise...
return inquirer.prompt([
{
type: "confirm",
name: "es6",
message: "Are you using ECMAScript 6 features?",
default: false
},
{
type: "confirm",
name: "modules",
message: "Are you using ES6 modules?",
default: false,
when(answers) {
return answers.es6 === true;
}
},
{
type: "checkbox",
name: "env",
message: "Where will your code run?",
default: ["browser"],
choices: [{ name: "Browser", value: "browser" }, { name: "Node", value: "node" }]
},
{
type: "confirm",
name: "commonjs",
message: "Do you use CommonJS?",
default: false,
when(answers) {
return answers.env.some(env => env === "browser");
}
},
{
type: "confirm",
name: "jsx",
message: "Do you use JSX?",
default: false
},
{
type: "confirm",
name: "react",
message: "Do you use React?",
default: false,
when(answers) {
return answers.jsx;
}
}
]).then(secondAnswers => {
// early exit if you are using automatic style generation
if (earlyAnswers.source === "auto") {
const combinedAnswers = Object.assign({}, earlyAnswers, secondAnswers);
const config = processAnswers(combinedAnswers);
installModules(config);
writeFile(config, earlyAnswers.format);
return void 0;
}
// continue with the style questions otherwise...
return inquirer.prompt([
{
type: "list",
name: "indent",
message: "What style of indentation do you use?",
default: "tab",
choices: [{ name: "Tabs", value: "tab" }, { name: "Spaces", value: 4 }]
},
{
type: "list",
name: "quotes",
message: "What quotes do you use for strings?",
default: "double",
choices: [{ name: "Double", value: "double" }, { name: "Single", value: "single" }]
},
{
type: "list",
name: "linebreak",
message: "What line endings do you use?",
default: "unix",
choices: [{ name: "Unix", value: "unix" }, { name: "Windows", value: "windows" }]
},
{
type: "confirm",
name: "semi",
message: "Do you require semicolons?",
default: true
},
{
type: "list",
name: "format",
message: "What format do you want your config file to be in?",
default: "JavaScript",
choices: ["JavaScript", "YAML", "JSON"]
}
]).then(answers => {
const totalAnswers = Object.assign({}, earlyAnswers, secondAnswers, answers);
const config = processAnswers(totalAnswers);
installModules(config);
writeFile(config, answers.format);
});
});
});
}
//------------------------------------------------------------------------------
// Public Interface
//------------------------------------------------------------------------------
const init = {
getConfigForStyleGuide,
hasESLintVersionConflict,
processAnswers,
/* istanbul ignore next */initializeConfig() {
return promptUser();
}
};
module.exports = init;