extract help command

src/cli/commands/help.js

@@ -0,0 +1,40 @@
+/* @flow */
+
+import * as commands from './index.js';
+import type {Reporter} from '../../reporters/index.js';
+import type Config from '../../config.js';
+import NpmRegistry from '../../registries/npm-registry.js';
+import parsePackageName from '../../util/parse-package-name.js';
+import {sortAlpha, hyphenate} from '../../util/misc.js';
+const chalk = require('chalk');
+
+export async function run(
+  config: Config,
+  reporter: Reporter,
+  commander: Object,
+  args: Array<string>,
+): Promise<void> {
+  const getDocsLink = (name) => `https://yarnpkg.com/en/docs/cli/${name || ''}`;
+  const getDocsInfo = (name) => 'Visit ' + chalk.bold(getDocsLink(name)) + ' for documentation about this command.';
+
+  if (args.length) {
+    const helpCommand = hyphenate(args[0]);
+    if (commands[helpCommand]) {
+      commander.on('--help', () => console.log('  ' + getDocsInfo(helpCommand) + '\n'));
+    }
+  } else {
+    commander.on('--help', () => {
+      console.log('  Commands:\n');
+      for (const name of Object.keys(commands).sort(sortAlpha)) {
+        if (commands[name].useless) {
+          continue;
+        }
+
+        console.log(`    - ${hyphenate(name)}`);
+      }
+      console.log('\n  Run `' + chalk.bold('yarn help COMMAND') + '` for more information on specific commands.');
+      console.log('  Visit ' + chalk.bold(getDocsLink()) + ' to learn more about Yarn.\n');
+    });
+  }
+  commander.help();
+}

src/cli/commands/index.js

@@ -9,6 +9,7 @@ import * as clean from './clean.js'; export {clean};
 import * as config from './config.js'; export {config};
 import * as generateLockEntry from './generate-lock-entry.js'; export {generateLockEntry};
 import * as global from './global.js'; export {global};
+import * as help from './help.js'; export {help};
 import * as info from './info.js'; export {info};
 import * as init from './init.js'; export {init};
 import * as install from './install.js'; export {install};

src/cli/index.js

@@ -98,27 +98,8 @@ const getDocsLink = (name) => `https://yarnpkg.com/en/docs/cli/${name || ''}`;
 const getDocsInfo = (name) => 'Visit ' + chalk.bold(getDocsLink(name)) + ' for documentation about this command.';
 
 //
-if (commandName === 'help' || commandName === '--help' || commandName === '-h') {
+if (commandName === '--help' || commandName === '-h') {
   commandName = 'help';
-  if (args.length) {
-    const helpCommand = hyphenate(args[0]);
-    if (commands[helpCommand]) {
-      commander.on('--help', () => console.log('  ' + getDocsInfo(helpCommand) + '\n'));
-    }
-  } else {
-    commander.on('--help', () => {
-      console.log('  Commands:\n');
-      for (const name of Object.keys(commands).sort(sortAlpha)) {
-        if (commands[name].useless) {
-          continue;
-        }
-
-        console.log(`    - ${hyphenate(name)}`);
-      }
-      console.log('\n  Run `' + chalk.bold('yarn help COMMAND') + '` for more information on specific commands.');
-      console.log('  Visit ' + chalk.bold(getDocsLink()) + ' to learn more about Yarn.\n');
-    });
-  }
 }
 
 // if no args or command name looks like a flag then default to `install`
@@ -159,7 +140,7 @@ if (command && typeof command.setFlags === 'function') {
   command.setFlags(commander);
 }
 
-if (commandName === 'help' || args.indexOf('--help') >= 0 || args.indexOf('-h') >= 0) {
+if (args.indexOf('--help') >= 0 || args.indexOf('-h') >= 0) {
   const examples: Array<string> = (command && command.examples) || [];
   if (examples.length) {
     commander.on('--help', () => {
@@ -216,7 +197,7 @@ if (typeof command.hasWrapper === 'function') {
 if (commander.json) {
   outputWrapper = false;
 }
-if (outputWrapper) {
+if (outputWrapper && commandName !== 'help') {
   reporter.header(commandName, pkg);
 }