20988775bf
In case of multiple sessions to the same target, there's a race between sessions to create a secondary isolated world. As a result, we might end up having 2 execution contexts created for the needs of the secondary isolated world. This patch starts handling this race gracefully: instead of crashing, we can use either of the execution contexts and ignore the rest. Notably, the same race condition might happen if page reloads itself in-between the calls to `page.addEvaluateOnNewDocument` and `page.createIsolatedWorld`. Fixes #4197.
720 lines
20 KiB
JavaScript
720 lines
20 KiB
JavaScript
/**
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* Copyright 2019 Google Inc. All rights reserved.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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const fs = require('fs');
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const {helper, assert} = require('./helper');
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const {LifecycleWatcher} = require('./LifecycleWatcher');
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const {TimeoutError} = require('./Errors');
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const readFileAsync = helper.promisify(fs.readFile);
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/**
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* @unrestricted
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*/
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class DOMWorld {
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/**
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* @param {!Puppeteer.FrameManager} frameManager
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* @param {!Puppeteer.Frame} frame
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* @param {!Puppeteer.TimeoutSettings} timeoutSettings
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*/
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constructor(frameManager, frame, timeoutSettings) {
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this._frameManager = frameManager;
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this._frame = frame;
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this._timeoutSettings = timeoutSettings;
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/** @type {?Promise<!Puppeteer.ElementHandle>} */
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this._documentPromise = null;
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/** @type {!Promise<!Puppeteer.ExecutionContext>} */
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this._contextPromise;
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this._contextResolveCallback = null;
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this._setContext(null);
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/** @type {!Set<!WaitTask>} */
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this._waitTasks = new Set();
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this._detached = false;
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}
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/**
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* @return {!Puppeteer.Frame}
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*/
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frame() {
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return this._frame;
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}
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/**
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* @param {?Puppeteer.ExecutionContext} context
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*/
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_setContext(context) {
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if (context) {
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this._contextResolveCallback.call(null, context);
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this._contextResolveCallback = null;
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for (const waitTask of this._waitTasks)
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waitTask.rerun();
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} else {
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this._documentPromise = null;
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this._contextPromise = new Promise(fulfill => {
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this._contextResolveCallback = fulfill;
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});
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}
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}
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/**
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* @return {boolean}
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*/
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_hasContext() {
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return !this._contextResolveCallback;
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}
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_detach() {
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this._detached = true;
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for (const waitTask of this._waitTasks)
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waitTask.terminate(new Error('waitForFunction failed: frame got detached.'));
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}
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/**
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* @return {!Promise<!Puppeteer.ExecutionContext>}
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*/
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executionContext() {
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if (this._detached)
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throw new Error(`Execution Context is not available in detached frame "${this._frame.url()}" (are you trying to evaluate?)`);
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return this._contextPromise;
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}
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/**
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* @param {Function|string} pageFunction
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* @param {!Array<*>} args
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* @return {!Promise<!Puppeteer.JSHandle>}
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*/
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async evaluateHandle(pageFunction, ...args) {
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const context = await this.executionContext();
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return context.evaluateHandle(pageFunction, ...args);
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}
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/**
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* @param {Function|string} pageFunction
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* @param {!Array<*>} args
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* @return {!Promise<*>}
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*/
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async evaluate(pageFunction, ...args) {
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const context = await this.executionContext();
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return context.evaluate(pageFunction, ...args);
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}
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/**
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* @param {string} selector
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* @return {!Promise<?Puppeteer.ElementHandle>}
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*/
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async $(selector) {
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const document = await this._document();
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const value = await document.$(selector);
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return value;
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}
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/**
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* @return {!Promise<!Puppeteer.ElementHandle>}
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*/
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async _document() {
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if (this._documentPromise)
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return this._documentPromise;
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this._documentPromise = this.executionContext().then(async context => {
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const document = await context.evaluateHandle('document');
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return document.asElement();
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});
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return this._documentPromise;
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}
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/**
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* @param {string} expression
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* @return {!Promise<!Array<!Puppeteer.ElementHandle>>}
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*/
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async $x(expression) {
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const document = await this._document();
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const value = await document.$x(expression);
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return value;
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}
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/**
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* @param {string} selector
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* @param {Function|string} pageFunction
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* @param {!Array<*>} args
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* @return {!Promise<(!Object|undefined)>}
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*/
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async $eval(selector, pageFunction, ...args) {
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const document = await this._document();
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return document.$eval(selector, pageFunction, ...args);
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}
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/**
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* @param {string} selector
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* @param {Function|string} pageFunction
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* @param {!Array<*>} args
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* @return {!Promise<(!Object|undefined)>}
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*/
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async $$eval(selector, pageFunction, ...args) {
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const document = await this._document();
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const value = await document.$$eval(selector, pageFunction, ...args);
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return value;
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}
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/**
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* @param {string} selector
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* @return {!Promise<!Array<!Puppeteer.ElementHandle>>}
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*/
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async $$(selector) {
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const document = await this._document();
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const value = await document.$$(selector);
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return value;
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}
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/**
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* @return {!Promise<String>}
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*/
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async content() {
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return await this.evaluate(() => {
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let retVal = '';
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if (document.doctype)
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retVal = new XMLSerializer().serializeToString(document.doctype);
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if (document.documentElement)
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retVal += document.documentElement.outerHTML;
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return retVal;
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});
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}
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/**
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* @param {string} html
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* @param {!{timeout?: number, waitUntil?: string|!Array<string>}=} options
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*/
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async setContent(html, options = {}) {
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const {
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waitUntil = ['load'],
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timeout = this._timeoutSettings.navigationTimeout(),
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} = options;
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// We rely upon the fact that document.open() will reset frame lifecycle with "init"
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// lifecycle event. @see https://crrev.com/608658
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await this.evaluate(html => {
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document.open();
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document.write(html);
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document.close();
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}, html);
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const watcher = new LifecycleWatcher(this._frameManager, this._frame, waitUntil, timeout);
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const error = await Promise.race([
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watcher.timeoutOrTerminationPromise(),
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watcher.lifecyclePromise(),
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]);
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watcher.dispose();
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if (error)
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throw error;
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}
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/**
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* @param {!{url?: string, path?: string, content?: string, type?: string}} options
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* @return {!Promise<!Puppeteer.ElementHandle>}
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*/
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async addScriptTag(options) {
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const {
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url = null,
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path = null,
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content = null,
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type = ''
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} = options;
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if (url !== null) {
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try {
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const context = await this.executionContext();
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return (await context.evaluateHandle(addScriptUrl, url, type)).asElement();
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} catch (error) {
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throw new Error(`Loading script from ${url} failed`);
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}
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}
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if (path !== null) {
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let contents = await readFileAsync(path, 'utf8');
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contents += '//# sourceURL=' + path.replace(/\n/g, '');
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const context = await this.executionContext();
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return (await context.evaluateHandle(addScriptContent, contents, type)).asElement();
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}
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if (content !== null) {
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const context = await this.executionContext();
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return (await context.evaluateHandle(addScriptContent, content, type)).asElement();
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}
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throw new Error('Provide an object with a `url`, `path` or `content` property');
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/**
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* @param {string} url
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* @param {string} type
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* @return {!Promise<!HTMLElement>}
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*/
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async function addScriptUrl(url, type) {
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const script = document.createElement('script');
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script.src = url;
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if (type)
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script.type = type;
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const promise = new Promise((res, rej) => {
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script.onload = res;
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script.onerror = rej;
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});
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document.head.appendChild(script);
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await promise;
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return script;
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}
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/**
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* @param {string} content
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* @param {string} type
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* @return {!HTMLElement}
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*/
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function addScriptContent(content, type = 'text/javascript') {
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const script = document.createElement('script');
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script.type = type;
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script.text = content;
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let error = null;
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script.onerror = e => error = e;
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document.head.appendChild(script);
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if (error)
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throw error;
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return script;
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}
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}
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/**
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* @param {!{url?: string, path?: string, content?: string}} options
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* @return {!Promise<!Puppeteer.ElementHandle>}
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*/
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async addStyleTag(options) {
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const {
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url = null,
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path = null,
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content = null
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} = options;
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if (url !== null) {
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try {
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const context = await this.executionContext();
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return (await context.evaluateHandle(addStyleUrl, url)).asElement();
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} catch (error) {
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throw new Error(`Loading style from ${url} failed`);
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}
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}
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if (path !== null) {
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let contents = await readFileAsync(path, 'utf8');
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contents += '/*# sourceURL=' + path.replace(/\n/g, '') + '*/';
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const context = await this.executionContext();
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return (await context.evaluateHandle(addStyleContent, contents)).asElement();
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}
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if (content !== null) {
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const context = await this.executionContext();
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return (await context.evaluateHandle(addStyleContent, content)).asElement();
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}
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throw new Error('Provide an object with a `url`, `path` or `content` property');
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/**
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* @param {string} url
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* @return {!Promise<!HTMLElement>}
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*/
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async function addStyleUrl(url) {
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const link = document.createElement('link');
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link.rel = 'stylesheet';
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link.href = url;
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const promise = new Promise((res, rej) => {
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link.onload = res;
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link.onerror = rej;
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});
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document.head.appendChild(link);
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await promise;
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return link;
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}
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/**
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* @param {string} content
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* @return {!Promise<!HTMLElement>}
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*/
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async function addStyleContent(content) {
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const style = document.createElement('style');
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style.type = 'text/css';
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style.appendChild(document.createTextNode(content));
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const promise = new Promise((res, rej) => {
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style.onload = res;
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style.onerror = rej;
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});
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document.head.appendChild(style);
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await promise;
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return style;
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}
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}
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/**
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* @param {string} selector
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* @param {!{delay?: number, button?: "left"|"right"|"middle", clickCount?: number}=} options
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*/
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async click(selector, options) {
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const handle = await this.$(selector);
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assert(handle, 'No node found for selector: ' + selector);
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await handle.click(options);
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await handle.dispose();
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}
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/**
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* @param {string} selector
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*/
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async focus(selector) {
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const handle = await this.$(selector);
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assert(handle, 'No node found for selector: ' + selector);
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await handle.focus();
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await handle.dispose();
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}
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/**
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* @param {string} selector
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*/
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async hover(selector) {
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const handle = await this.$(selector);
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assert(handle, 'No node found for selector: ' + selector);
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await handle.hover();
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await handle.dispose();
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}
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/**
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* @param {string} selector
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* @param {!Array<string>} values
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* @return {!Promise<!Array<string>>}
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*/
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select(selector, ...values){
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for (const value of values)
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assert(helper.isString(value), 'Values must be strings. Found value "' + value + '" of type "' + (typeof value) + '"');
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return this.$eval(selector, (element, values) => {
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if (element.nodeName.toLowerCase() !== 'select')
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throw new Error('Element is not a <select> element.');
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const options = Array.from(element.options);
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element.value = undefined;
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for (const option of options) {
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option.selected = values.includes(option.value);
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if (option.selected && !element.multiple)
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break;
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}
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element.dispatchEvent(new Event('input', { 'bubbles': true }));
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element.dispatchEvent(new Event('change', { 'bubbles': true }));
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return options.filter(option => option.selected).map(option => option.value);
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}, values);
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}
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/**
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* @param {string} selector
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*/
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async tap(selector) {
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const handle = await this.$(selector);
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assert(handle, 'No node found for selector: ' + selector);
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await handle.tap();
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await handle.dispose();
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}
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/**
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* @param {string} selector
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* @param {string} text
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* @param {{delay: (number|undefined)}=} options
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*/
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async type(selector, text, options) {
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const handle = await this.$(selector);
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assert(handle, 'No node found for selector: ' + selector);
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await handle.type(text, options);
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await handle.dispose();
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}
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/**
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* @param {string} selector
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* @param {!{visible?: boolean, hidden?: boolean, timeout?: number}=} options
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* @return {!Promise<?Puppeteer.ElementHandle>}
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*/
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waitForSelector(selector, options) {
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return this._waitForSelectorOrXPath(selector, false, options);
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}
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/**
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* @param {string} xpath
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* @param {!{visible?: boolean, hidden?: boolean, timeout?: number}=} options
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* @return {!Promise<?Puppeteer.ElementHandle>}
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*/
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waitForXPath(xpath, options) {
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return this._waitForSelectorOrXPath(xpath, true, options);
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}
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/**
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* @param {Function|string} pageFunction
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* @param {!{polling?: string|number, timeout?: number}=} options
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* @return {!Promise<!Puppeteer.JSHandle>}
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*/
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waitForFunction(pageFunction, options = {}, ...args) {
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const {
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polling = 'raf',
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timeout = this._timeoutSettings.timeout(),
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} = options;
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return new WaitTask(this, pageFunction, 'function', polling, timeout, ...args).promise;
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}
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/**
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* @return {!Promise<string>}
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*/
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async title() {
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return this.evaluate(() => document.title);
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}
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/**
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* @param {string} selectorOrXPath
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* @param {boolean} isXPath
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* @param {!{visible?: boolean, hidden?: boolean, timeout?: number}=} options
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* @return {!Promise<?Puppeteer.ElementHandle>}
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*/
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async _waitForSelectorOrXPath(selectorOrXPath, isXPath, options = {}) {
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const {
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visible: waitForVisible = false,
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hidden: waitForHidden = false,
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timeout = this._timeoutSettings.timeout(),
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} = options;
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const polling = waitForVisible || waitForHidden ? 'raf' : 'mutation';
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const title = `${isXPath ? 'XPath' : 'selector'} "${selectorOrXPath}"${waitForHidden ? ' to be hidden' : ''}`;
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const waitTask = new WaitTask(this, predicate, title, polling, timeout, selectorOrXPath, isXPath, waitForVisible, waitForHidden);
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const handle = await waitTask.promise;
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if (!handle.asElement()) {
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await handle.dispose();
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return null;
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}
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return handle.asElement();
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/**
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* @param {string} selectorOrXPath
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* @param {boolean} isXPath
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* @param {boolean} waitForVisible
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* @param {boolean} waitForHidden
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* @return {?Node|boolean}
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*/
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function predicate(selectorOrXPath, isXPath, waitForVisible, waitForHidden) {
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const node = isXPath
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? document.evaluate(selectorOrXPath, document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue
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: document.querySelector(selectorOrXPath);
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if (!node)
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return waitForHidden;
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if (!waitForVisible && !waitForHidden)
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return node;
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const element = /** @type {Element} */ (node.nodeType === Node.TEXT_NODE ? node.parentElement : node);
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const style = window.getComputedStyle(element);
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const isVisible = style && style.visibility !== 'hidden' && hasVisibleBoundingBox();
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const success = (waitForVisible === isVisible || waitForHidden === !isVisible);
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return success ? node : null;
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/**
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* @return {boolean}
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*/
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function hasVisibleBoundingBox() {
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const rect = element.getBoundingClientRect();
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return !!(rect.top || rect.bottom || rect.width || rect.height);
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}
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}
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}
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}
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class WaitTask {
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/**
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* @param {!DOMWorld} domWorld
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* @param {Function|string} predicateBody
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* @param {string|number} polling
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* @param {number} timeout
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* @param {!Array<*>} args
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*/
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constructor(domWorld, predicateBody, title, polling, timeout, ...args) {
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if (helper.isString(polling))
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assert(polling === 'raf' || polling === 'mutation', 'Unknown polling option: ' + polling);
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else if (helper.isNumber(polling))
|
|
assert(polling > 0, 'Cannot poll with non-positive interval: ' + polling);
|
|
else
|
|
throw new Error('Unknown polling options: ' + polling);
|
|
|
|
this._domWorld = domWorld;
|
|
this._polling = polling;
|
|
this._timeout = timeout;
|
|
this._predicateBody = helper.isString(predicateBody) ? 'return (' + predicateBody + ')' : 'return (' + predicateBody + ')(...args)';
|
|
this._args = args;
|
|
this._runCount = 0;
|
|
domWorld._waitTasks.add(this);
|
|
this.promise = new Promise((resolve, reject) => {
|
|
this._resolve = resolve;
|
|
this._reject = reject;
|
|
});
|
|
// Since page navigation requires us to re-install the pageScript, we should track
|
|
// timeout on our end.
|
|
if (timeout) {
|
|
const timeoutError = new TimeoutError(`waiting for ${title} failed: timeout ${timeout}ms exceeded`);
|
|
this._timeoutTimer = setTimeout(() => this.terminate(timeoutError), timeout);
|
|
}
|
|
this.rerun();
|
|
}
|
|
|
|
/**
|
|
* @param {!Error} error
|
|
*/
|
|
terminate(error) {
|
|
this._terminated = true;
|
|
this._reject(error);
|
|
this._cleanup();
|
|
}
|
|
|
|
async rerun() {
|
|
const runCount = ++this._runCount;
|
|
/** @type {?Puppeteer.JSHandle} */
|
|
let success = null;
|
|
let error = null;
|
|
try {
|
|
success = await (await this._domWorld.executionContext()).evaluateHandle(waitForPredicatePageFunction, this._predicateBody, this._polling, this._timeout, ...this._args);
|
|
} catch (e) {
|
|
error = e;
|
|
}
|
|
|
|
if (this._terminated || runCount !== this._runCount) {
|
|
if (success)
|
|
await success.dispose();
|
|
return;
|
|
}
|
|
|
|
// Ignore timeouts in pageScript - we track timeouts ourselves.
|
|
// If the frame's execution context has already changed, `frame.evaluate` will
|
|
// throw an error - ignore this predicate run altogether.
|
|
if (!error && await this._domWorld.evaluate(s => !s, success).catch(e => true)) {
|
|
await success.dispose();
|
|
return;
|
|
}
|
|
|
|
// When the page is navigated, the promise is rejected.
|
|
// We will try again in the new execution context.
|
|
if (error && error.message.includes('Execution context was destroyed'))
|
|
return;
|
|
|
|
// We could have tried to evaluate in a context which was already
|
|
// destroyed.
|
|
if (error && error.message.includes('Cannot find context with specified id'))
|
|
return;
|
|
|
|
if (error)
|
|
this._reject(error);
|
|
else
|
|
this._resolve(success);
|
|
|
|
this._cleanup();
|
|
}
|
|
|
|
_cleanup() {
|
|
clearTimeout(this._timeoutTimer);
|
|
this._domWorld._waitTasks.delete(this);
|
|
this._runningTask = null;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @param {string} predicateBody
|
|
* @param {string} polling
|
|
* @param {number} timeout
|
|
* @return {!Promise<*>}
|
|
*/
|
|
async function waitForPredicatePageFunction(predicateBody, polling, timeout, ...args) {
|
|
const predicate = new Function('...args', predicateBody);
|
|
let timedOut = false;
|
|
if (timeout)
|
|
setTimeout(() => timedOut = true, timeout);
|
|
if (polling === 'raf')
|
|
return await pollRaf();
|
|
if (polling === 'mutation')
|
|
return await pollMutation();
|
|
if (typeof polling === 'number')
|
|
return await pollInterval(polling);
|
|
|
|
/**
|
|
* @return {!Promise<*>}
|
|
*/
|
|
function pollMutation() {
|
|
const success = predicate.apply(null, args);
|
|
if (success)
|
|
return Promise.resolve(success);
|
|
|
|
let fulfill;
|
|
const result = new Promise(x => fulfill = x);
|
|
const observer = new MutationObserver(mutations => {
|
|
if (timedOut) {
|
|
observer.disconnect();
|
|
fulfill();
|
|
}
|
|
const success = predicate.apply(null, args);
|
|
if (success) {
|
|
observer.disconnect();
|
|
fulfill(success);
|
|
}
|
|
});
|
|
observer.observe(document, {
|
|
childList: true,
|
|
subtree: true,
|
|
attributes: true
|
|
});
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* @return {!Promise<*>}
|
|
*/
|
|
function pollRaf() {
|
|
let fulfill;
|
|
const result = new Promise(x => fulfill = x);
|
|
onRaf();
|
|
return result;
|
|
|
|
function onRaf() {
|
|
if (timedOut) {
|
|
fulfill();
|
|
return;
|
|
}
|
|
const success = predicate.apply(null, args);
|
|
if (success)
|
|
fulfill(success);
|
|
else
|
|
requestAnimationFrame(onRaf);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @param {number} pollInterval
|
|
* @return {!Promise<*>}
|
|
*/
|
|
function pollInterval(pollInterval) {
|
|
let fulfill;
|
|
const result = new Promise(x => fulfill = x);
|
|
onTimeout();
|
|
return result;
|
|
|
|
function onTimeout() {
|
|
if (timedOut) {
|
|
fulfill();
|
|
return;
|
|
}
|
|
const success = predicate.apply(null, args);
|
|
if (success)
|
|
fulfill(success);
|
|
else
|
|
setTimeout(onTimeout, pollInterval);
|
|
}
|
|
}
|
|
}
|
|
|
|
module.exports = {DOMWorld};
|