chore(itest): guard playwright tarball size and bundled deps

Adds two installation tests: one asserts upper bounds on the packed
playwright-core and playwright tarball sizes, the other asserts lower
bounds on the number of inlined npm packages per bundle LICENSE,
parsed from the "Total Packages" summary line.

Author: pavelfeldman

tests/installation/bundle-licenses.spec.ts

@@ -0,0 +1,75 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import fs from 'fs';
+import path from 'path';
+import { test, expect } from './npmTest';
+
+// Lower bounds on the number of inlined npm packages per LICENSE. If a bundle drops below
+// these, something is broken with bundle generation or dependencies were silently removed.
+const EXPECTED: Record<string, Record<string, number>> = {
+  'playwright-core': {
+    'lib/coreBundle.js.LICENSE': 45,
+    'lib/utilsBundle.js.LICENSE': 80,
+  },
+  'playwright': {
+    'lib/matchers/expect.js.LICENSE': 30,
+    'lib/transform/esmLoader.js.LICENSE': 10,
+    'lib/transform/babelBundle.js.LICENSE': 65,
+  },
+};
+
+async function collectLicenses(dir: string): Promise<string[]> {
+  const result: string[] = [];
+  const walk = async (d: string) => {
+    const entries = await fs.promises.readdir(d, { withFileTypes: true }).catch(() => []);
+    for (const e of entries) {
+      const p = path.join(d, e.name);
+      if (e.isDirectory())
+        await walk(p);
+      else if (e.name.endsWith('.LICENSE'))
+        result.push(p);
+    }
+  };
+  await walk(dir);
+  return result.sort();
+}
+
+for (const [pkg, licenses] of Object.entries(EXPECTED)) {
+  test(`${pkg} bundles ship .LICENSE files with expected package counts`, async ({ exec, tmpWorkspace }) => {
+    const registry = JSON.parse(await fs.promises.readFile(path.join(__dirname, '.registry.json'), 'utf8'));
+    const tarball: string = registry[pkg];
+    expect(tarball, `no tarball recorded for ${pkg} in .registry.json`).toBeTruthy();
+
+    const extractDir = path.join(tmpWorkspace, `extract-${pkg}`);
+    await fs.promises.mkdir(extractDir, { recursive: true });
+    await exec('tar', '-xzf', tarball, '-C', extractDir);
+
+    const libDir = path.join(extractDir, 'package', 'lib');
+    const found = await collectLicenses(libDir);
+    const expected = Object.keys(licenses).map(p => path.join(libDir, ...p.slice('lib/'.length).split('/'))).sort();
+    expect(found, `LICENSE files under ${pkg}/lib do not match the expected set — update EXPECTED`).toEqual(expected);
+
+    for (const [relPath, minPackages] of Object.entries(licenses)) {
+      const absPath = path.join(extractDir, 'package', relPath);
+      const contents = await fs.promises.readFile(absPath, 'utf8');
+      const match = contents.match(/^Total Packages: (\d+)$/m);
+      expect(match, `${pkg}/${relPath} is missing the "Total Packages" summary line`).toBeTruthy();
+      const count = Number(match![1]);
+      test.info().annotations.push({ type: 'licenses', description: `${pkg}/${relPath}: ${count} packages` });
+      expect(count, `${pkg}/${relPath} lists only ${count} packages, expected at least ${minPackages}`).toBeGreaterThanOrEqual(minPackages);
+    }
+  });
+}

tests/installation/bundle-size.spec.ts

@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import fs from 'fs';
+import path from 'path';
+import { test, expect } from './npmTest';
+
+const THRESHOLDS: Record<string, number> = {
+  'playwright-core': 7 * 1024 * 1024,
+  'playwright': 3 * 1024 * 1024,
+};
+
+for (const [pkg, maxBytes] of Object.entries(THRESHOLDS)) {
+  test(`${pkg} tarball stays under ${(maxBytes / 1024 / 1024).toFixed(2)} MB`, async () => {
+    const registry = JSON.parse(await fs.promises.readFile(path.join(__dirname, '.registry.json'), 'utf8'));
+    const tarball: string = registry[pkg];
+    expect(tarball, `no tarball recorded for ${pkg} in .registry.json`).toBeTruthy();
+    const { size } = await fs.promises.stat(tarball);
+    test.info().annotations.push({ type: 'size', description: `${pkg}: ${size} bytes` });
+    expect(size, `${pkg} tarball ${tarball} is ${size} bytes, limit ${maxBytes}`).toBeLessThanOrEqual(maxBytes);
+  });
+}