test: add e2e test for ivy opt-out

Author: Alan Agius

tests/legacy-cli/e2e/tests/ivy/ivy-opt-out.ts

@@ -0,0 +1,45 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+import { replaceInFile } from '../../utils/fs';
+import { request } from '../../utils/http';
+import { killAllProcesses, ng } from '../../utils/process';
+import { createProject, ngServe } from '../../utils/project';
+
+export default async function() {
+  try {
+    await createProject('ivy-project-opt-out', '--enable-ivy');
+    // trigger an Ivy builds to process packages with NGCC
+    await ng('e2e', '--prod');
+
+    // View Engine (NGC) compilation should work after running NGCC from Webpack
+    await replaceInFile('tsconfig.app.json', '"enableIvy": true', '"enableIvy": false');
+
+    // verify that VE compilation works during runtime
+    await ng('e2e', '--prod');
+
+    // verify that it is not Ivy
+    await ngServe('--prod');
+    // Verify the index.html
+    const body = await request('http://localhost:4200/');
+    if (!body.match(/<app-root><\/app-root>/)) {
+      throw new Error('Response does not match expected value.');
+    }
+
+    // Verify it's compiled with NGC
+    const mainUrlMatch = body.match(/src="(main\.[a-z0-9]{0,32}\.js)"/);
+    const mainUrl = mainUrlMatch && mainUrlMatch[1];
+    const main = await request('http://localhost:4200/' + mainUrl);
+
+    if (main.match(/ngComponentDef\s*=/)) {
+      throw new Error('Loaded Ivy but expected View Engine applicatiom.');
+    }
+
+  } finally {
+    await killAllProcesses();
+  }
+}