Implements set version (#7862)

Author: arcanis

src/cli/commands/init.js

@@ -19,6 +19,7 @@ export function setFlags(commander: Object) {
   commander.option('-y, --yes', 'use default options');
   commander.option('-p, --private', 'use default options and private true');
   commander.option('-i, --install <value>', 'install a specific Yarn release');
+  commander.option('-2', 'generates the project using Yarn 2');
 }
 
 export function hasWrapper(commander: Object, args: Array<string>): boolean {
@@ -28,12 +29,14 @@ export function hasWrapper(commander: Object, args: Array<string>): boolean {
 export const shouldRunInCurrentCwd = true;
 
 export async function run(config: Config, reporter: Reporter, flags: Object, args: Array<string>): Promise<void> {
-  if (flags.install) {
+  const installVersion = flags[`2`] ? `berry` : flags.install;
+
+  if (installVersion) {
     const lockfilePath = path.resolve(config.cwd, 'yarn.lock');
     if (!await fs.exists(lockfilePath)) {
       await fs.writeFile(lockfilePath, '');
     }
-    await child.spawn(NODE_BIN_PATH, [process.argv[1], 'policies', 'set-version', flags.install], {
+    await child.spawn(NODE_BIN_PATH, [process.argv[1], 'policies', 'set-version', installVersion], {
       stdio: 'inherit',
       cwd: config.cwd,
     });

src/cli/commands/policies.js

@@ -114,13 +114,15 @@ const {run, setFlags, examples} = buildSubCommands('policies', {
 
     let bundleUrl;
     let bundleVersion;
+    let isV2 = false;
 
     if (range === 'nightly' || range === 'nightlies') {
       bundleUrl = 'https://nightly.yarnpkg.com/latest.js';
       bundleVersion = 'nightly';
     } else if (range === 'berry' || range === 'v2' || range === '2') {
       bundleUrl = 'https://github.com/yarnpkg/berry/raw/master/packages/berry-cli/bin/berry.js';
       bundleVersion = 'berry';
+      isV2 = true;
     } else {
       const releases = await fetchReleases(config, {
         includePrereleases: allowRc,
@@ -145,18 +147,29 @@ const {run, setFlags, examples} = buildSubCommands('policies', {
     reporter.log(`Downloading ${chalk.green(bundleUrl)}...`);
 
     const bundle = await fetchBundle(config, bundleUrl);
-    const rc = getRcConfigForFolder(config.lockfileFolder);
 
     const yarnPath = path.resolve(config.lockfileFolder, `.yarn/releases/yarn-${bundleVersion}.js`);
     reporter.log(`Saving it into ${chalk.magenta(yarnPath)}...`);
     await fs.mkdirp(path.dirname(yarnPath));
     await fs.writeFile(yarnPath, bundle);
     await fs.chmod(yarnPath, 0o755);
 
-    const rcPath = `${config.lockfileFolder}/.yarnrc`;
-    reporter.log(`Updating ${chalk.magenta(rcPath)}...`);
-    rc['yarn-path'] = path.relative(config.lockfileFolder, yarnPath);
-    await fs.writeFilePreservingEol(rcPath, `${stringify(rc)}\n`);
+    const targetPath = path.relative(config.lockfileFolder, yarnPath).replace(/\\/g, '/');
+
+    if (isV2) {
+      const rcPath = `${config.lockfileFolder}/.yarnrc.yml`;
+      reporter.log(`Updating ${chalk.magenta(rcPath)}...`);
+
+      await fs.writeFilePreservingEol(rcPath, `yarnPath: ${JSON.stringify(yarnPath)}\n`);
+    } else {
+      const rcPath = `${config.lockfileFolder}/.yarnrc`;
+      reporter.log(`Updating ${chalk.magenta(rcPath)}...`);
+
+      const rc = getRcConfigForFolder(config.lockfileFolder);
+      rc['yarn-path'] = targetPath;
+
+      await fs.writeFilePreservingEol(rcPath, `${stringify(rc)}\n`);
+    }
 
     reporter.log(`Done!`);
   },

src/cli/index.js

@@ -187,7 +187,11 @@ export async function main({
     commandName = 'install';
     isKnownCommand = true;
   }
-
+  if (commandName === ('set': string) && args[0] === 'version') {
+    commandName = ('policies': string);
+    args.splice(0, 1, 'set-version');
+    isKnownCommand = true;
+  }
   if (!isKnownCommand) {
     // if command is not recognized, then set default to `run`
     args.unshift(commandName);