Update tests for Turbopack (#59354)

## What?

- Add support for `experimental.externalDir` -- Was already supported,
just makes Turbopack not fail on that config option
- Skipped `with-babel` test because it tests Babel
- Skipped `swc-warnings` test because it tests Babel
- Skipped `config-resolve-alias` as it tests webpack config
- Skipped `undefined-webpack-config` as it tests webpack config

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Closes NEXT-1817

Author: timneutkens

packages/next/src/lib/turbopack-warning.ts

@@ -69,6 +69,7 @@ const supportedTurbopackNextConfigOptions = [
   'experimental.useLightningcss',
   'experimental.windowHistorySupport',
   'experimental.instrumentationHook',
+  'experimental.externalDir',
 
   // Experimental options that don't affect compilation
   'experimental.ppr',
@@ -131,7 +132,6 @@ const supportedTurbopackNextConfigOptions = [
   // 'experimental.craCompat',
   // 'experimental.disablePostcssPresetEnv',
   // 'experimental.esmExternals',
-  // 'experimental.externalDir',
   // This is used to force swc-loader to run regardless of finding Babel.
   // 'experimental.forceSwcTransforms',
   // 'experimental.fullySpecified',

test/e2e/app-dir/with-babel/with-babel.test.ts

@@ -1,23 +1,26 @@
 import { createNextDescribe } from 'e2e-utils'
 
-createNextDescribe(
-  'with babel',
-  {
-    files: __dirname,
-    skipDeployment: true,
-  },
-  ({ next, isNextStart }) => {
-    it('should support babel in app dir', async () => {
-      const $ = await next.render$('/')
-      expect($('h1').text()).toBe('hello')
-    })
-
-    if (isNextStart) {
-      it('should contain og package files in middleware', async () => {
-        const middleware = await next.readFile('.next/server/middleware.js')
-        // @vercel/og default font should be bundled
-        expect(middleware).not.toContain('noto-sans-v27-latin-regular.ttf')
+// Tests Babel, not needed for Turbopack
+;(process.env.TURBOPACK ? describe.skip : describe)('with babel', () => {
+  createNextDescribe(
+    'with babel',
+    {
+      files: __dirname,
+      skipDeployment: true,
+    },
+    ({ next, isNextStart }) => {
+      it('should support babel in app dir', async () => {
+        const $ = await next.render$('/')
+        expect($('h1').text()).toBe('hello')
       })
+
+      if (isNextStart) {
+        it('should contain og package files in middleware', async () => {
+          const middleware = await next.readFile('.next/server/middleware.js')
+          // @vercel/og default font should be bundled
+          expect(middleware).not.toContain('noto-sans-v27-latin-regular.ttf')
+        })
+      }
     }
-  }
-)
+  )
+})

test/e2e/swc-warnings/index.test.ts

@@ -2,35 +2,39 @@ import { createNext } from 'e2e-utils'
 import { NextInstance } from 'test/lib/next-modes/base'
 import { renderViaHTTP } from 'next-test-utils'
 
-describe('swc warnings by default', () => {
-  let next: NextInstance
+// Tests Babel, not needed for Turbopack
+;(process.env.TURBOPACK ? describe.skip : describe)(
+  'swc warnings by default',
+  () => {
+    let next: NextInstance
 
-  beforeAll(async () => {
-    next = await createNext({
-      files: {
-        'pages/index.js': `
+    beforeAll(async () => {
+      next = await createNext({
+        files: {
+          'pages/index.js': `
           export default function Page() { 
             return <p>hello world</p>
           } 
         `,
-        '.babelrc': `
+          '.babelrc': `
           {
             "presets": ["next/babel"]
           }
         `,
-      },
-      dependencies: {},
+        },
+        dependencies: {},
+      })
     })
-  })
-  afterAll(() => next.destroy())
+    afterAll(() => next.destroy())
 
-  it('should have warning', async () => {
-    await renderViaHTTP(next.url, '/')
-    expect(next.cliOutput).toContain(
-      'Disabled SWC as replacement for Babel because of custom Babel configuration'
-    )
-  })
-})
+    it('should have warning', async () => {
+      await renderViaHTTP(next.url, '/')
+      expect(next.cliOutput).toContain(
+        'Disabled SWC as replacement for Babel because of custom Babel configuration'
+      )
+    })
+  }
+)
 
 describe('can force swc', () => {
   let next: NextInstance

test/integration/config-resolve-alias/test/index.test.js

@@ -3,14 +3,21 @@
 import { join } from 'path'
 import { runNextCommand } from 'next-test-utils'
 
-describe('Invalid resolve alias', () => {
-  it('should show relevant error when webpack resolve alias is wrong', async () => {
-    const { stderr } = await runNextCommand(['build', join(__dirname, '..')], {
-      stderr: true,
-    })
+// Skip in Turbopack as it does not support `config.resolve.alias` from webpack.
+;(process.env.TURBOPACK ? describe.skip : describe)(
+  'Invalid resolve alias',
+  () => {
+    it('should show relevant error when webpack resolve alias is wrong', async () => {
+      const { stderr } = await runNextCommand(
+        ['build', join(__dirname, '..')],
+        {
+          stderr: true,
+        }
+      )
 
-    expect(stderr).toMatch(
-      'webpack config.resolve.alias was incorrectly overridden. https://'
-    )
-  })
-})
+      expect(stderr).toMatch(
+        'webpack config.resolve.alias was incorrectly overridden. https://'
+      )
+    })
+  }
+)

test/integration/undefined-webpack-config/test/index.test.js

@@ -7,29 +7,36 @@ const appDir = join(__dirname, '../')
 const expectedErr =
   /Webpack config is undefined. You may have forgot to return properly from within the "webpack" method of your next.config.js/
 
-describe('undefined webpack config error', () => {
-  ;(process.env.TURBOPACK ? describe.skip : describe)('production mode', () => {
-    it.skip('should show in production mode', async () => {
-      const result = await nextBuild(appDir, [], {
-        stdout: true,
-        stderr: true,
-      })
-      expect(result.stderr || '' + result.stdout || '').toMatch(expectedErr)
-    })
-  })
+// Tests webpack, not needed for Turbopack
+;(process.env.TURBOPACK ? describe.skip : describe)(
+  'undefined webpack config error',
+  () => {
+    ;(process.env.TURBOPACK ? describe.skip : describe)(
+      'production mode',
+      () => {
+        it.skip('should show in production mode', async () => {
+          const result = await nextBuild(appDir, [], {
+            stdout: true,
+            stderr: true,
+          })
+          expect(result.stderr || '' + result.stdout || '').toMatch(expectedErr)
+        })
+      }
+    )
 
-  it('should show in dev mode', async () => {
-    let output = ''
+    it('should show in dev mode', async () => {
+      let output = ''
 
-    await launchApp(appDir, await findPort(), {
-      onStderr(msg) {
-        output += msg || ''
-      },
-      ontStdout(msg) {
-        output += msg || ''
-      },
-    })
+      await launchApp(appDir, await findPort(), {
+        onStderr(msg) {
+          output += msg || ''
+        },
+        ontStdout(msg) {
+          output += msg || ''
+        },
+      })
 
-    expect(output).toMatch(expectedErr)
-  })
-})
+      expect(output).toMatch(expectedErr)
+    })
+  }
+)