chore: refactor Browser.js into seperate files (#2097)

This patch splits Browser.js into multiple separate files.

lib/Browser.js

@@ -14,9 +14,10 @@
  * limitations under the License.
  */
 
-const {helper} = require('./helper');
-const Page = require('./Page');
+const { helper } = require('./helper');
+const Target = require('./Target');
 const EventEmitter = require('events');
+const TaskQueue = require('./TaskQueue');
 
 class Browser extends EventEmitter {
   /**
@@ -63,10 +64,11 @@ class Browser extends EventEmitter {
   }
 
   /**
-   * @param {{targetInfo: !Target.TargetInfo}} event
+   * @param {{targetInfo: !Puppeteer.TargetInfo}} event
    */
   async _targetCreated(event) {
-    const target = new Target(this, event.targetInfo);
+    const targetInfo = event.targetInfo;
+    const target = new Target(targetInfo, () => this._connection.createSession(targetInfo.targetId), this._ignoreHTTPSErrors, this._appMode, this._screenshotTaskQueue);
     console.assert(!this._targets.has(event.targetInfo.targetId), 'Target should not exist before targetCreated');
     this._targets.set(event.targetInfo.targetId, target);
 
@@ -87,12 +89,16 @@ class Browser extends EventEmitter {
   }
 
   /**
-   * @param {{targetInfo: !Target.TargetInfo}} event
+   * @param {{targetInfo: !Puppeteer.TargetInfo}} event
    */
   _targetInfoChanged(event) {
     const target = this._targets.get(event.targetInfo.targetId);
     console.assert(target, 'target should exist before targetInfoChanged');
+    const previousURL = target.url();
+    const wasInitialized = target._isInitialized;
     target._targetInfoChanged(event.targetInfo);
+    if (wasInitialized && previousURL !== target.url())
+      this.emit(Browser.Events.TargetChanged, target);
   }
 
   /**
@@ -103,7 +109,7 @@ class Browser extends EventEmitter {
   }
 
   /**
-   * @return {!Promise<!Page>}
+   * @return {!Promise<!Puppeteer.Page>}
    */
   async newPage() {
     const {targetId} = await this._connection.send('Target.createTarget', {url: 'about:blank'});
@@ -121,7 +127,7 @@ class Browser extends EventEmitter {
   }
 
   /**
-   * @return {!Promise<!Array<!Page>>}
+   * @return {!Promise<!Array<!Puppeteer.Page>>}
    */
   async pages() {
     const pages = await Promise.all(this.targets().map(target => target.page()));
@@ -171,101 +177,4 @@ Browser.Events = {
 
 helper.tracePublicAPI(Browser);
 
-class TaskQueue {
-  constructor() {
-    this._chain = Promise.resolve();
-  }
-
-  /**
-   * @param {function()} task
-   * @return {!Promise}
-   */
-  postTask(task) {
-    const result = this._chain.then(task);
-    this._chain = result.catch(() => {});
-    return result;
-  }
-}
-
-class Target {
-  /**
-   * @param {!Browser} browser
-   * @param {!Target.TargetInfo} targetInfo
-   */
-  constructor(browser, targetInfo) {
-    this._browser = browser;
-    this._targetId = targetInfo.targetId;
-    this._targetInfo = targetInfo;
-    /** @type {?Promise<!Page>} */
-    this._pagePromise = null;
-    this._initializedPromise = new Promise(fulfill => this._initializedCallback = fulfill);
-    this._isClosedPromise = new Promise(fulfill => this._closedCallback = fulfill);
-    this._isInitialized = this._targetInfo.type !== 'page' || this._targetInfo.url !== '';
-    if (this._isInitialized)
-      this._initializedCallback(true);
-  }
-
-  /**
-   * @return {!Promise<!Puppeteer.CDPSession>}
-   */
-  createCDPSession() {
-    return this._browser._connection.createSession(this._targetId);
-  }
-
-  /**
-   * @return {!Promise<?Page>}
-   */
-  async page() {
-    if (this._targetInfo.type === 'page' && !this._pagePromise) {
-      this._pagePromise = this._browser._connection.createSession(this._targetId)
-          .then(client => Page.create(client, this, this._browser._ignoreHTTPSErrors, this._browser._appMode, this._browser._screenshotTaskQueue));
-    }
-    return this._pagePromise;
-  }
-
-  /**
-   * @return {string}
-   */
-  url() {
-    return this._targetInfo.url;
-  }
-
-  /**
-   * @return {"page"|"service_worker"|"other"|"browser"}
-   */
-  type() {
-    const type = this._targetInfo.type;
-    if (type === 'page' || type === 'service_worker' || type === 'browser')
-      return type;
-    return 'other';
-  }
-
-  /**
-   * @param {!Target.TargetInfo} targetInfo
-   */
-  _targetInfoChanged(targetInfo) {
-    const previousURL = this._targetInfo.url;
-    this._targetInfo = targetInfo;
-
-    if (!this._isInitialized && (this._targetInfo.type !== 'page' || this._targetInfo.url !== '')) {
-      this._isInitialized = true;
-      this._initializedCallback(true);
-      return;
-    }
-
-    if (previousURL !== targetInfo.url)
-      this._browser.emit(Browser.Events.TargetChanged, this);
-  }
-}
-helper.tracePublicAPI(Target);
-
-/**
- * @typedef {Object} Target.TargetInfo
- * @property {string} type
- * @property {string} targetId
- * @property {string} title
- * @property {string} url
- * @property {boolean} attached
- */
-
-module.exports = { Browser, TaskQueue, Target };
+module.exports = Browser;

lib/Launcher.js

@@ -19,7 +19,7 @@ const removeFolder = require('rimraf');
 const childProcess = require('child_process');
 const BrowserFetcher = require('./BrowserFetcher');
 const {Connection} = require('./Connection');
-const {Browser} = require('./Browser');
+const Browser = require('./Browser');
 const readline = require('readline');
 const fs = require('fs');
 const {helper} = require('./helper');

lib/Target.js

@@ -0,0 +1,79 @@
+const Page = require('./Page');
+const {helper} = require('./helper');
+
+class Target {
+  /**
+   * @param {!Puppeteer.TargetInfo} targetInfo
+   * @param {!function():!Promise<!Puppeteer.CDPSession>} sessionFactory
+   * @param {boolean} ignoreHTTPSErrors
+   * @param {boolean} appMode
+   * @param {!Puppeteer.TaskQueue} screenshotTaskQueue
+   */
+  constructor(targetInfo, sessionFactory, ignoreHTTPSErrors, appMode, screenshotTaskQueue) {
+    this._targetInfo = targetInfo;
+    this._targetId = targetInfo.targetId;
+    this._sessionFactory = sessionFactory;
+    this._ignoreHTTPSErrors = ignoreHTTPSErrors;
+    this._appMode = appMode;
+    this._screenshotTaskQueue = screenshotTaskQueue;
+    /** @type {?Promise<!Puppeteer.Page>} */
+    this._pagePromise = null;
+    this._initializedPromise = new Promise(fulfill => this._initializedCallback = fulfill);
+    this._isClosedPromise = new Promise(fulfill => this._closedCallback = fulfill);
+    this._isInitialized = this._targetInfo.type !== 'page' || this._targetInfo.url !== '';
+    if (this._isInitialized)
+      this._initializedCallback(true);
+  }
+
+  /**
+   * @return {!Promise<!Puppeteer.CDPSession>}
+   */
+  createCDPSession() {
+    return this._sessionFactory();
+  }
+
+  /**
+   * @return {!Promise<?Page>}
+   */
+  async page() {
+    if (this._targetInfo.type === 'page' && !this._pagePromise) {
+      this._pagePromise = this._sessionFactory()
+          .then(client => Page.create(client, this, this._ignoreHTTPSErrors, this._appMode, this._screenshotTaskQueue));
+    }
+    return this._pagePromise;
+  }
+
+  /**
+   * @return {string}
+   */
+  url() {
+    return this._targetInfo.url;
+  }
+
+  /**
+   * @return {"page"|"service_worker"|"other"|"browser"}
+   */
+  type() {
+    const type = this._targetInfo.type;
+    if (type === 'page' || type === 'service_worker' || type === 'browser')
+      return type;
+    return 'other';
+  }
+
+  /**
+   * @param {!Puppeteer.TargetInfo} targetInfo
+   */
+  _targetInfoChanged(targetInfo) {
+    this._targetInfo = targetInfo;
+
+    if (!this._isInitialized && (this._targetInfo.type !== 'page' || this._targetInfo.url !== '')) {
+      this._isInitialized = true;
+      this._initializedCallback(true);
+      return;
+    }
+  }
+}
+
+helper.tracePublicAPI(Target);
+
+module.exports = Target;

lib/TaskQueue.js

@@ -0,0 +1,17 @@
+class TaskQueue {
+  constructor() {
+    this._chain = Promise.resolve();
+  }
+
+  /**
+   * @param {function()} task
+   * @return {!Promise}
+   */
+  postTask(task) {
+    const result = this._chain.then(task);
+    this._chain = result.catch(() => {});
+    return result;
+  }
+}
+
+module.exports = TaskQueue;

lib/externs.d.ts

@@ -1,6 +1,8 @@
 import { Connection as RealConnection, CDPSession as RealCDPSession } from './Connection.js';
-import {Browser as RealBrowser, TaskQueue as RealTaskQueue, Target as RealTarget} from './Browser.js';
+import * as RealBrowser from './Browser.js';
+import * as RealTarget from './Target.js';
 import * as RealPage from './Page.js';
+import * as RealTaskQueue from './TaskQueue.js';
 import {Mouse as RealMouse, Keyboard as RealKeyboard, Touchscreen as RealTouchscreen}  from './Input.js';
 import {Frame as RealFrame, FrameManager as RealFrameManager}  from './FrameManager.js';
 import {JSHandle as RealJSHandle, ExecutionContext as RealExecutionContext}  from './ExecutionContext.js';
@@ -30,4 +32,12 @@ export interface ConnectionTransport extends NodeJS.EventEmitter {
   close();
 }
 
+export interface TargetInfo {
+  type: string;
+  targetId: string;
+  title: string;
+  url: string;
+  attached: boolean;
+}
+
 export interface ChildProcess extends child_process.ChildProcess {}