chore: add test runner for testing pptr in a browser

.eslintignore

@@ -11,3 +11,4 @@ lib/
 # in the Puppeteer src, so it trips up the ESLint-TypeScript parser.
 utils/doclint/generate_types/test/test.ts
 vendor/
+web-test-runner.config.mjs

.eslintrc.js

@@ -125,6 +125,17 @@ module.exports = {
                     "default": "array-simple"
                 }]
             }
+        },
+        {
+            "files": ["test-browser/**/*.js"],
+            "parserOptions": {
+                "sourceType": "module"
+            },
+            "env": {
+                "es6": true,
+                "browser": true,
+                "es2020": true
+            },        
         }
     ]
 };

.travis.yml

@@ -57,6 +57,13 @@ jobs:
       script:
         - travis_retry npm run unit
 
+    - node_js: "12.16.3"
+      name: 'Browser tests: Linux/Chromium'
+      env:
+        - CHROMIUM=true
+      script:
+        - travis_retry npm run test-browser
+
     # This bot runs all the extra checks that aren't the main Puppeteer unit tests
     - node_js: "10.19.0"
       name: 'Extra tests: Linux/Chromium'

package.json

@@ -8,12 +8,14 @@
     "node": ">=10.18.1"
   },
   "scripts": {
+    "test-browser": "wtr",
+    "test-browser-watch": "wtr --watch",
     "unit": "npm run tsc-cjs && mocha --config mocha-config/puppeteer-unit-tests.js",
     "unit-with-coverage": "cross-env COVERAGE=1 npm run unit",
     "assert-unit-coverage": "cross-env COVERAGE=1 mocha --config mocha-config/coverage-tests.js",
     "funit": "PUPPETEER_PRODUCT=firefox npm run unit",
     "debug-unit": "node --inspect-brk test/test.js",
-    "test": "npm run tsc && npm run lint --silent && npm run unit-with-coverage && npm run test-types",
+    "test": "npm run tsc && npm run lint --silent && npm run unit-with-coverage && npm run test-browser && npm run test-types",
     "prepare": "node typescript-if-required.js",
     "prepublishOnly": "npm run tsc",
     "dev-install": "npm run tsc && node install.js",
@@ -69,6 +71,7 @@
     "@types/ws": "^7.2.4",
     "@typescript-eslint/eslint-plugin": "^2.28.0",
     "@typescript-eslint/parser": "^2.28.0",
+    "@web/test-runner": "^0.6.40",
     "commonmark": "^0.28.1",
     "cross-env": "^5.0.5",
     "dependency-cruiser": "^9.7.0",

test-browser/debug.spec.js

@@ -0,0 +1,65 @@
+/**
+ * Copyright 2020 Google Inc. All rights reserved.
+ *
+ * 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 { debug } from '../lib/esm/puppeteer/common/Debug.js';
+import expect from '../node_modules/expect/build-es5/index.js';
+
+describe('debug', () => {
+  let originalLog;
+  let logs;
+  beforeEach(() => {
+    originalLog = console.log;
+    logs = [];
+    console.log = (...args) => {
+      logs.push(args);
+    };
+  });
+
+  afterEach(() => {
+    console.log = originalLog;
+  });
+
+  it('should return a function', async () => {
+    expect(debug('foo')).toBeInstanceOf(Function);
+  });
+
+  it('does not log to the console if __PUPPETEER_DEBUG global is not set', async () => {
+    const debugFn = debug('foo');
+    debugFn('lorem', 'ipsum');
+
+    expect(logs.length).toEqual(0);
+  });
+
+  it('logs to the console if __PUPPETEER_DEBUG global is set to *', async () => {
+    globalThis.__PUPPETEER_DEBUG = '*';
+    const debugFn = debug('foo');
+    debugFn('lorem', 'ipsum');
+
+    expect(logs.length).toEqual(1);
+    expect(logs).toEqual([['foo:', 'lorem', 'ipsum']]);
+  });
+
+  it('logs only messages matching the __PUPPETEER_DEBUG prefix', async () => {
+    globalThis.__PUPPETEER_DEBUG = 'foo';
+    const debugFoo = debug('foo');
+    const debugBar = debug('bar');
+    debugFoo('a');
+    debugBar('b');
+
+    expect(logs.length).toEqual(1);
+    expect(logs).toEqual([['foo:', 'a']]);
+  });
+});

web-test-runner.config.js

@@ -0,0 +1,30 @@
+/**
+ * Copyright 2020 Google Inc. All rights reserved.
+ *
+ * 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.
+ */
+
+module.exports = {
+  files: ['test-browser/**/*.spec.js'],
+  plugins: [
+    {
+      // turn expect UMD into an es module
+      name: 'esmify-expect',
+      transform(context) {
+        if (context.path === '/node_modules/expect/build-es5/index.js') {
+          return `const module = {}; const exports = {};\n${context.body};\n export default module.exports;`;
+        }
+      },
+    },
+  ],
+};