Turbopack build: Properly isolate scss/webpack-error test (#67995)

When this test was in `test/integration` it tried to hack around Sass
always being installed. By leveraging the test isolation helpers we can
just opt to not installing `sass` which ensures it matches reality. This
doesn't fix the test with Turbopack enabled yet but it does highlight
the real error, instead of showing a strange resolving error about a
non-existent sass-begone package.

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test/e2e/app-dir/scss/webpack-error/webpack-error.test.ts

@@ -1,49 +1,32 @@
 /* eslint-env jest */
-
-import { remove } from 'fs-extra'
-import { nextBuild } from 'next-test-utils'
-import { join } from 'path'
-import { quote as shellQuote } from 'shell-quote'
-// In order for the global isNextStart to be set
-import 'e2e-utils'
+import { nextTestSetup } from 'e2e-utils'
 
 describe('SCSS Support', () => {
-  ;(Boolean((global as any).isNextStart) ? describe : describe.skip)(
-    'production only',
-    () => {
-      describe('Friendly Webpack Error', () => {
-        const appDir = __dirname
-
-        const mockFile = join(appDir, 'mock.js')
+  const { next, isNextDev } = nextTestSetup({
+    files: __dirname,
+    skipStart: true,
+    skipDeployment: true,
+  })
+  // Production only test
+  ;(isNextDev ? describe.skip : describe)('Friendly Webpack Error', () => {
+    it('should be a friendly error successfully', async () => {
+      const { exitCode, cliOutput } = await next.build()
+      expect(exitCode).toBe(1)
 
-        beforeAll(async () => {
-          await remove(join(appDir, '.next'))
-        })
-        it('should be a friendly error successfully', async () => {
-          const { code, stderr } = await nextBuild(appDir, [], {
-            env: { NODE_OPTIONS: shellQuote([`--require`, mockFile]) },
-            stderr: true,
-          })
-          let cleanScssErrMsg =
-            '\n\n' +
-            './styles/global.scss\n' +
-            "To use Next.js' built-in Sass support, you first need to install `sass`.\n" +
-            'Run `npm i sass` or `yarn add sass` inside your workspace.\n' +
-            '\n' +
-            'Learn more: https://nextjs.org/docs/messages/install-sass\n'
+      expect(cliOutput).toContain('./styles/global.scss')
+      expect(cliOutput).toContain(
+        "To use Next.js' built-in Sass support, you first need to install `sass`."
+      )
+      expect(cliOutput).toContain(
+        'Run `npm i sass` or `yarn add sass` inside your workspace.'
+      )
+      expect(cliOutput).toContain(
+        'Learn more: https://nextjs.org/docs/messages/install-sass'
+      )
 
-          // eslint-disable-next-line
-          expect(code).toBe(1)
-          // eslint-disable-next-line
-          expect(stderr).toContain('Failed to compile.')
-          // eslint-disable-next-line
-          expect(stderr).toContain(cleanScssErrMsg)
-          // eslint-disable-next-line
-          expect(stderr).not.toContain('css-loader')
-          // eslint-disable-next-line
-          expect(stderr).not.toContain('sass-loader')
-        })
-      })
-    }
-  )
+      expect(cliOutput).toContain('Failed to compile.')
+      expect(cliOutput).not.toContain('css-loader')
+      expect(cliOutput).not.toContain('sass-loader')
+    })
+  })
 })

test/turbopack-build-tests-manifest.json

@@ -3853,7 +3853,7 @@
     "test/e2e/app-dir/scss/webpack-error/webpack-error.test.ts": {
       "passed": [],
       "failed": [
-        "SCSS Support production only Friendly Webpack Error should be a friendly error successfully"
+        "SCSS Support Friendly Webpack Error should be a friendly error successfully"
       ],
       "pending": [],
       "flakey": [],