test(cna): split and refactor (vercel#63921)

> Note: Did not add additional tests or make many changes to the utils,
possible refactoring on the following PR.

This PR split the legacy tests into four sections to improve the
maintenance and concurrency of CNA tests:

- `prompts`: target prompt interactions. `Y/n`
- `examples`:  target `--example` and `--example-path` flags.
- `templates`: target the flag values such as `--app`, `--eslint`, etc.
- `package-manager`: target package managers: npm, pnpm, yarn, bun

---------

Co-authored-by: JJ Kasper <[email protected]>

package.json

@@ -118,7 +118,6 @@
     "abort-controller": "3.0.0",
     "alex": "9.1.0",
     "amphtml-validator": "1.0.35",
-    "ansi-escapes": "4.3.2",
     "async-sema": "3.0.1",
     "browserslist": "4.22.2",
     "buffer": "5.6.0",

test/integration/create-next-app/examples.test.ts

@@ -0,0 +1,256 @@
+import {
+  EXAMPLE_PATH,
+  EXAMPLE_REPO,
+  FULL_EXAMPLE_PATH,
+  projectFilesShouldExist,
+  projectFilesShouldNotExist,
+  shouldBeTemplateProject,
+  run,
+  useTempDir,
+} from './utils'
+
+describe('create-next-app --example', () => {
+  it('should create on valid Next.js example name', async () => {
+    await useTempDir(async (cwd) => {
+      const projectName = 'valid-example'
+      const res = await run([projectName, '--example', 'basic-css'], {
+        cwd,
+      })
+      expect(res.exitCode).toBe(0)
+      projectFilesShouldExist({
+        cwd,
+        projectName,
+        files: [
+          '.gitignore',
+          'package.json',
+          'app/page.tsx',
+          'app/layout.tsx',
+          'node_modules/next',
+        ],
+      })
+    })
+  })
+
+  it('should create with GitHub URL', async () => {
+    await useTempDir(async (cwd) => {
+      const projectName = 'github-url'
+      const res = await run([projectName, '--example', FULL_EXAMPLE_PATH], {
+        cwd,
+      })
+
+      expect(res.exitCode).toBe(0)
+      projectFilesShouldExist({
+        cwd,
+        projectName,
+        files: [
+          '.gitignore',
+          'package.json',
+          'app/page.tsx',
+          'app/layout.tsx',
+          'node_modules/next',
+        ],
+      })
+    })
+  })
+
+  it('should create with GitHub URL trailing slash', async () => {
+    await useTempDir(async (cwd) => {
+      const projectName = 'github-url-trailing-slash'
+      const res = await run(
+        [
+          projectName,
+          '--example',
+          // since vercel/examples is not a template repo, we use the following
+          // GH#39665
+          'https://github.com/vercel/nextjs-portfolio-starter/',
+        ],
+        {
+          cwd,
+        }
+      )
+
+      expect(res.exitCode).toBe(0)
+      projectFilesShouldExist({
+        cwd,
+        projectName,
+        files: [
+          '.gitignore',
+          'package.json',
+          'pages/index.mdx',
+          'node_modules/next',
+        ],
+      })
+    })
+  })
+
+  it('should create with GitHub URL and --example-path', async () => {
+    await useTempDir(async (cwd) => {
+      const projectName = 'github-url-and-example-path'
+      const res = await run(
+        [
+          projectName,
+          '--js',
+          '--no-tailwind',
+          '--eslint',
+          '--example',
+          EXAMPLE_REPO,
+          '--example-path',
+          EXAMPLE_PATH,
+        ],
+        {
+          cwd,
+        }
+      )
+
+      expect(res.exitCode).toBe(0)
+      projectFilesShouldExist({
+        cwd,
+        projectName,
+        files: [
+          '.gitignore',
+          'package.json',
+          'app/page.tsx',
+          'app/layout.tsx',
+          'node_modules/next',
+        ],
+      })
+    })
+  })
+
+  it('should use --example-path over the GitHub URL', async () => {
+    await useTempDir(async (cwd) => {
+      const projectName = 'example-path-over-github-url'
+      const res = await run(
+        [
+          projectName,
+          '--js',
+          '--no-tailwind',
+          '--eslint',
+          '--example',
+          FULL_EXAMPLE_PATH,
+          '--example-path',
+          EXAMPLE_PATH,
+        ],
+        {
+          cwd,
+        }
+      )
+
+      expect(res.exitCode).toBe(0)
+      projectFilesShouldExist({
+        cwd,
+        projectName,
+        files: [
+          '.gitignore',
+          'package.json',
+          'app/page.tsx',
+          'app/layout.tsx',
+          'node_modules/next',
+        ],
+      })
+    })
+  })
+
+  // TODO: investigate why this test stalls on yarn install when
+  // stdin is piped instead of inherited on windows
+  if (process.platform !== 'win32') {
+    it('should fall back to default template if failed to download', async () => {
+      await useTempDir(async (cwd) => {
+        const projectName = 'fallback-to-default'
+        const res = await run(
+          [
+            projectName,
+            '--js',
+            '--no-tailwind',
+            '--eslint',
+            '--app',
+            '--example',
+            '__internal-testing-retry',
+            '--import-alias=@/*',
+          ],
+          {
+            cwd,
+            input: '\n', // 'Yes' to retry
+            stdio: 'pipe',
+          }
+        )
+
+        expect(res.exitCode).toBe(0)
+        shouldBeTemplateProject({
+          cwd,
+          projectName,
+          template: 'app',
+          mode: 'js',
+        })
+      })
+    })
+  }
+
+  it('should create if --example value is default', async () => {
+    await useTempDir(async (cwd) => {
+      const projectName = 'example-default'
+      const res = await run(
+        [
+          projectName,
+          '--js',
+          '--no-tailwind',
+          '--eslint',
+          '--example',
+          'default',
+          '--import-alias=@/*',
+        ],
+        {
+          cwd,
+        }
+      )
+
+      expect(res.exitCode).toBe(0)
+      shouldBeTemplateProject({
+        cwd,
+        projectName,
+        template: 'default',
+        mode: 'js',
+      })
+    })
+  })
+
+  it('should not create if --example flag value is invalid', async () => {
+    await useTempDir(async (cwd) => {
+      const projectName = 'invalid-example'
+      const res = await run([projectName, '--example', 'not a real example'], {
+        cwd,
+        reject: false,
+      })
+
+      expect(res.exitCode).toBe(1)
+      projectFilesShouldNotExist({
+        cwd,
+        projectName,
+        files: ['package.json'],
+      })
+    })
+  })
+
+  it('should not create if --example flag value is absent', async () => {
+    await useTempDir(async (cwd) => {
+      const projectName = 'no-example'
+      const res = await run(
+        [
+          projectName,
+          '--ts',
+          '--app',
+          '--eslint',
+          '--no-src-dir',
+          '--no-tailwind',
+          '--example',
+        ],
+        {
+          cwd,
+          reject: false,
+        }
+      )
+
+      expect(res.exitCode).toBe(1)
+    })
+  })
+})