add missing-babelrc automigration

code/lib/cli/src/automigrate/fixes/index.ts

@@ -17,6 +17,7 @@ import { autodocsTrue } from './autodocs-true';
 import { sveltekitFramework } from './sveltekit-framework';
 import { addReact } from './add-react';
 import { nodeJsRequirement } from './nodejs-requirement';
+import { missingBabelRc } from './missing-babelrc';
 
 export * from '../types';
 
@@ -38,4 +39,5 @@ export const fixes: Fix[] = [
   mdx1to2,
   autodocsTrue,
   addReact,
+  missingBabelRc,
 ];

code/lib/cli/src/automigrate/fixes/missing-babelrc.test.ts

@@ -0,0 +1,91 @@
+/* eslint-disable no-underscore-dangle */
+/// <reference types="@types/jest" />;
+
+import path from 'path';
+import type { JsPackageManager } from '../../js-package-manager';
+import { missingBabelRc } from './missing-babelrc';
+
+// eslint-disable-next-line global-require, jest/no-mocks-import
+jest.mock('fs-extra', () => require('../../../../../__mocks__/fs-extra'));
+
+const babelContent = JSON.stringify({
+  sourceType: 'unambiguous',
+  presets: [
+    [
+      '@babel/preset-env',
+      {
+        targets: {
+          chrome: 100,
+        },
+      },
+    ],
+    '@babel/preset-typescript',
+    '@babel/preset-react',
+  ],
+  plugins: [],
+});
+
+const check = async ({ packageJson = {}, main = {}, extraFiles }: any) => {
+  if (extraFiles) {
+    // eslint-disable-next-line global-require
+    require('fs-extra').__setMockFiles({
+      [path.join('.storybook', 'main.js')]: `module.exports = ${JSON.stringify(main)};`,
+      ...extraFiles,
+    });
+  }
+  const packageManager = {
+    retrievePackageJson: () => ({ dependencies: {}, devDependencies: {}, ...packageJson }),
+  } as JsPackageManager;
+  return missingBabelRc.check({ packageManager });
+};
+
+describe('missing-babelrc fix', () => {
+  it('skips when babelrc config is present', async () => {
+    const packageJson = {
+      devDependencies: {
+        '@storybook/react': '^7.0.0',
+        '@storybook/react-webpack5': '^7.0.0',
+      },
+    };
+
+    // different babel extensions
+    await expect(
+      check({ extraFiles: { '.babelrc': babelContent }, packageJson })
+    ).resolves.toBeNull();
+    await expect(
+      check({ extraFiles: { '.babelrc.json': babelContent }, packageJson })
+    ).resolves.toBeNull();
+    await expect(
+      check({ extraFiles: { 'babel.config.json': babelContent }, packageJson })
+    ).resolves.toBeNull();
+
+    // babel field in package.json
+    await expect(
+      check({ packageJson: { ...packageJson, babel: babelContent } })
+    ).resolves.toBeNull();
+  });
+
+  it('skips when using a framework that provides babel config', async () => {
+    const packageJson = {
+      devDependencies: {
+        '@storybook/react': '^7.0.0',
+        '@storybook/nextjs': '^7.0.0',
+      },
+    };
+
+    await expect(check({ packageJson })).resolves.toBeNull();
+  });
+
+  it('prompts when babelrc file is missing and framework does not provide babel config', async () => {
+    const packageJson = {
+      devDependencies: {
+        '@storybook/react': '^7.0.0',
+        '@storybook/react-webpack5': '^7.0.0',
+      },
+    };
+
+    await expect(check({ packageJson })).resolves.toBe({
+      needsBabelRc: true,
+    });
+  });
+});

code/lib/cli/src/automigrate/fixes/missing-babelrc.ts

@@ -0,0 +1,91 @@
+import chalk from 'chalk';
+import dedent from 'ts-dedent';
+import semver from 'semver';
+import { getStorybookInfo } from '@storybook/core-common';
+import { loadPartialConfigAsync } from '@babel/core';
+import { readConfig } from '@storybook/csf-tools';
+import type { Fix } from '../types';
+
+interface MissingBabelRcOptions {
+  needsBabelRc: boolean;
+}
+
+const logger = console;
+
+const frameworksThatNeedBabelConfig = [
+  '@storybook/angular',
+  '@storybook/react-webpack5',
+  '@storybook/vue-webpack5',
+  '@storybook/vue3-webpack5',
+  '@storybook/preact-webpack5',
+  '@storybook/html-webpack5',
+  '@storybook/react-vite',
+  '@storybook/vue-vite',
+  '@storybook/vue3-vite',
+  '@storybook/preact-vite',
+  '@storybook/html-vite',
+];
+
+export const missingBabelRc: Fix<MissingBabelRcOptions> = {
+  id: 'missing-babelrc',
+  promptOnly: true,
+
+  async check({ packageManager }) {
+    const packageJson = packageManager.retrievePackageJson();
+    const { mainConfig, version: storybookVersion } = getStorybookInfo(packageJson);
+
+    const storybookCoerced = storybookVersion && semver.coerce(storybookVersion)?.version;
+    if (!storybookCoerced) {
+      throw new Error(dedent`
+        ❌ Unable to determine storybook version.
+        🤔 Are you running automigrate from your project directory?
+      `);
+    }
+
+    if (!semver.gte(storybookCoerced, '7.0.0')) {
+      return null;
+    }
+
+    if (!mainConfig) {
+      logger.warn('Unable to find storybook main.js config, skipping');
+      return null;
+    }
+
+    const main = await readConfig(mainConfig);
+
+    const frameworkField = main.getFieldValue(['framework']);
+    const frameworkPackage =
+      typeof frameworkField === 'string' ? frameworkField : frameworkField?.name;
+
+    if (frameworksThatNeedBabelConfig.includes(frameworkPackage)) {
+      const config = await loadPartialConfigAsync();
+      if (!config.config && !packageJson.babel) {
+        return { needsBabelRc: true };
+      }
+    }
+
+    return null;
+  },
+  prompt() {
+    return dedent`
+      ${chalk.bold(
+        chalk.red('Attention')
+      )}: We could not automatically make this change. You'll need to do it manually.
+
+      Storybook now uses Babel mode v7 exclusively. In 6.x, Storybook provided its own babel settings out of the box. Now, Storybook's uses your project's babel settings (.babelrc, babel.config.js, etc.) instead.
+
+      In the new mode, Storybook expects you to provide a configuration file. If you want a configuration file that's equivalent to the 6.x default, you can run the following command in your project directory:
+
+      ${chalk.blue('npx sb@next babelrc')}
+
+      This will create a ${chalk.blue(
+        '.babelrc.json'
+      )} file with some basic configuration and add new package devDependencies accordingly.
+
+      Please see the migration guide for more information:
+      ${chalk.yellow(
+        'https://github.com/storybookjs/storybook/blob/next/MIGRATION.md#babel-mode-v7-exclusively'
+      )}
+    `;
+  },
+};