feat: introduce puppeteer-firefox (#3628)

This adds a proof-of-concept of `puppeteer-firefox`.
This consists of two parts:
- `//experimental/juggler` - patches to apply to Firefox.
- `//experimental/puppeteer-firefox` - front-end code to
be merged with Puppeteer.

As things become more stable, we'll gradually move it out of
the experimental folder.

experimental/puppeteer-firefox/test/jshandle.spec.js

@@ -0,0 +1,157 @@
+/**
+ * Copyright 2018 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.
+ */
+const utils = require('./utils');
+
+module.exports.addTests = function({testRunner, expect, product}) {
+  const {describe, xdescribe, fdescribe} = testRunner;
+  const {it, fit, xit} = testRunner;
+  const {beforeAll, beforeEach, afterAll, afterEach} = testRunner;
+
+  const FFOX = product === 'firefox';
+  const CHROME = product === 'chromium';
+
+  describe('Page.evaluateHandle', function() {
+    it('should work', async({page, server}) => {
+      const windowHandle = await page.evaluateHandle(() => window);
+      expect(windowHandle).toBeTruthy();
+    });
+    it('should accept object handle as an argument', async({page, server}) => {
+      const navigatorHandle = await page.evaluateHandle(() => navigator);
+      const text = await page.evaluate(e => e.userAgent, navigatorHandle);
+      expect(text).toContain('Mozilla');
+    });
+    it('should accept object handle to primitive types', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => 5);
+      const isFive = await page.evaluate(e => Object.is(e, 5), aHandle);
+      expect(isFive).toBeTruthy();
+    });
+    it('should accept object handle to unserializable value', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => Infinity);
+      expect(await page.evaluate(e => Object.is(e, Infinity), aHandle)).toBe(true);
+    });
+    it('should use the same JS wrappers', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => {
+        window.FOO = 123;
+        return window;
+      });
+      expect(await page.evaluate(e => e.FOO, aHandle)).toBe(123);
+    });
+    it('should work with primitives', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => {
+        window.FOO = 123;
+        return window;
+      });
+      expect(await page.evaluate(e => e.FOO, aHandle)).toBe(123);
+    });
+  });
+
+  describe('JSHandle.jsonValue', function() {
+    it('should work', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => ({foo: 'bar'}));
+      const json = await aHandle.jsonValue();
+      expect(json).toEqual({foo: 'bar'});
+    });
+    // This relies on Chrome's internal serialization. We can either repeat it
+    // in FFOX, or migrate to JSON.stringify() logic altogether.
+    (FFOX ? xit : it)('should not work with dates', async({page, server}) => {
+      const dateHandle = await page.evaluateHandle(() => new Date('2017-09-26T00:00:00.000Z'));
+      const json = await dateHandle.jsonValue();
+      expect(json).toEqual({});
+    });
+    it('should throw for circular objects', async({page, server}) => {
+      const windowHandle = await page.evaluateHandle('window');
+      let error = null;
+      await windowHandle.jsonValue().catch(e => error = e);
+      expect(error).not.toBe(null);
+    });
+  });
+
+  describe('JSHandle.toString', function() {
+    it('should work for primitives', async({page, server}) => {
+      const numberHandle = await page.evaluateHandle(() => 2);
+      expect(numberHandle.toString()).toBe('JSHandle:2');
+      const stringHandle = await page.evaluateHandle(() => 'a');
+      expect(stringHandle.toString()).toBe('JSHandle:a');
+    });
+    it('should work for complicated objects', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => window);
+      expect(aHandle.toString()).toBe('JSHandle@object');
+    });
+    it('should work with different subtypes', async({page, server}) => {
+      expect((await page.evaluateHandle('(function(){})')).toString()).toBe('JSHandle@function');
+      expect((await page.evaluateHandle('12')).toString()).toBe('JSHandle:12');
+      expect((await page.evaluateHandle('true')).toString()).toBe('JSHandle:true');
+      expect((await page.evaluateHandle('undefined')).toString()).toBe('JSHandle:undefined');
+      expect((await page.evaluateHandle('"foo"')).toString()).toBe('JSHandle:foo');
+      expect((await page.evaluateHandle('Symbol()')).toString()).toBe('JSHandle@symbol');
+      expect((await page.evaluateHandle('new Map()')).toString()).toBe('JSHandle@map');
+      expect((await page.evaluateHandle('new Set()')).toString()).toBe('JSHandle@set');
+      expect((await page.evaluateHandle('[]')).toString()).toBe('JSHandle@array');
+      expect((await page.evaluateHandle('null')).toString()).toBe('JSHandle:null');
+      expect((await page.evaluateHandle('/foo/')).toString()).toBe('JSHandle@regexp');
+      expect((await page.evaluateHandle('document.body')).toString()).toBe('JSHandle@node');
+      expect((await page.evaluateHandle('new Date()')).toString()).toBe('JSHandle@date');
+      expect((await page.evaluateHandle('new WeakMap()')).toString()).toBe('JSHandle@weakmap');
+      expect((await page.evaluateHandle('new WeakSet()')).toString()).toBe('JSHandle@weakset');
+      expect((await page.evaluateHandle('new Error()')).toString()).toBe('JSHandle@error');
+      expect((await page.evaluateHandle('new Int32Array()')).toString()).toBe('JSHandle@typedarray');
+      expect((await page.evaluateHandle('new Proxy({}, {})')).toString()).toBe('JSHandle@proxy');
+    });
+  });
+
+  describe('JSHandle.getProperties', function() {
+    it('should work', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => ({
+        foo: 'bar'
+      }));
+      const properties = await aHandle.getProperties();
+      const foo = properties.get('foo');
+      expect(foo).toBeTruthy();
+      expect(await foo.jsonValue()).toBe('bar');
+    });
+    it('should return even non-own properties', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => {
+        class A {
+          constructor() {
+            this.a = '1';
+          }
+        }
+        class B extends A {
+          constructor() {
+            super();
+            this.b = '2';
+          }
+        }
+        return new B();
+      });
+      const properties = await aHandle.getProperties();
+      expect(await properties.get('a').jsonValue()).toBe('1');
+      expect(await properties.get('b').jsonValue()).toBe('2');
+    });
+  });
+
+  describe('JSHandle.getProperty', function() {
+    it('should work', async({page, server}) => {
+      const aHandle = await page.evaluateHandle(() => ({
+        one: 1,
+        two: 2,
+        three: 3
+      }));
+      const twoHandle = await aHandle.getProperty('two');
+      expect(await twoHandle.jsonValue()).toEqual(2);
+    });
+  });
+};