text: /**
   * Copyright 2017 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 fs = require('fs');
  const EventEmitter = require('events');
  const {helper, assert} = require('./helper');
  const {ExecutionContext, JSHandle} = require('./ExecutionContext');
  const ElementHandle = require('./ElementHandle');
  
  const readFileAsync = helper.promisify(fs.readFile);
  
  class FrameManager extends EventEmitter {
    /**
     * @param {!Puppeteer.CDPSession} client
     * @param {!Protocol.Page.FrameTree} frameTree
     * @param {!Puppeteer.Page} page
     */
    constructor(client, frameTree, page) {
      super();
      this._client = client;
      this._page = page;
      /** @type {!Map<string, !Frame>} */
      this._frames = new Map();
      /** @type {!Map<number, !ExecutionContext>} */
      this._contextIdToContext = new Map();
  
      this._client.on('Page.frameAttached', event => this._onFrameAttached(event.frameId, event.parentFrameId));
      this._client.on('Page.frameNavigated', event => this._onFrameNavigated(event.frame));
      this._client.on('Page.navigatedWithinDocument', event => this._onFrameNavigatedWithinDocument(event.frameId, event.url));
      this._client.on('Page.frameDetached', event => this._onFrameDetached(event.frameId));
      this._client.on('Page.frameStoppedLoading', event => this._onFrameStoppedLoading(event.frameId));
      this._client.on('Runtime.executionContextCreated', event => this._onExecutionContextCreated(event.context));
      this._client.on('Runtime.executionContextDestroyed', event => this._onExecutionContextDestroyed(event.executionContextId));
      this._client.on('Runtime.executionContextsCleared', event => this._onExecutionContextsCleared());
      this._client.on('Page.lifecycleEvent', event => this._onLifecycleEvent(event));
  
      this._handleFrameTree(frameTree);
    }
  
    /**
     * @param {!Protocol.Page.lifecycleEventPayload} event
     */
    _onLifecycleEvent(event) {
      const frame = this._frames.get(event.frameId);
      if (!frame)
        return;
      frame._onLifecycleEvent(event.loaderId, event.name);
      this.emit(FrameManager.Events.LifecycleEvent, frame);
    }
  
    /**
     * @param {string} frameId
     */
    _onFrameStoppedLoading(frameId) {
      const frame = this._frames.get(frameId);
      if (!frame)
        return;
      frame._onLoadingStopped();
      this.emit(FrameManager.Events.LifecycleEvent, frame);
    }
  
    /**
     * @param {!Protocol.Page.FrameTree} frameTree
     */
    _handleFrameTree(frameTree) {
      if (frameTree.frame.parentId)
        this._onFrameAttached(frameTree.frame.id, frameTree.frame.parentId);
      this._onFrameNavigated(frameTree.frame);
      if (!frameTree.childFrames)
        return;
  
      for (const child of frameTree.childFrames)
        this._handleFrameTree(child);
    }
  
    /**
     * @return {!Frame}
     */
    mainFrame() {
      return this._mainFrame;
    }
  
    /**
     * @return {!Array<!Frame>}
     */
    frames() {
      return Array.from(this._frames.values());
    }
  
    /**
     * @param {!string} frameId
     * @return {?Frame}
     */
    frame(frameId) {
      return this._frames.get(frameId) || null;
    }
  
    /**
     * @param {string} frameId
     * @param {?string} parentFrameId
     * @return {?Frame}
     */
    _onFrameAttached(frameId, parentFrameId) {
      if (this._frames.has(frameId))
        return;
      assert(parentFrameId);
      const parentFrame = this._frames.get(parentFrameId);
      const frame = new Frame(this._client, parentFrame, frameId);
      this._frames.set(frame._id, frame);
      this.emit(FrameManager.Events.FrameAttached, frame);
    }
  
    /**
     * @param {!Protocol.Page.Frame} framePayload
     */
    _onFrameNavigated(framePayload) {
      const isMainFrame = !framePayload.parentId;
      let frame = isMainFrame ? this._mainFrame : this._frames.get(framePayload.id);
      assert(isMainFrame || frame, 'We either navigate top level or have old version of the navigated frame');
  
      // Detach all child frames first.
      if (frame) {
        for (const child of frame.childFrames())
          this._removeFramesRecursively(child);
      }
  
      // Update or create main frame.
      if (isMainFrame) {
        if (frame) {
          // Update frame id to retain frame identity on cross-process navigation.
          this._frames.delete(frame._id);
          frame._id = framePayload.id;
        } else {
          // Initial main frame navigation.
          frame = new Frame(this._client, null, framePayload.id);
        }
        this._frames.set(framePayload.id, frame);
        this._mainFrame = frame;
      }
  
      // Update frame payload.
      frame._navigated(framePayload);
  
      this.emit(FrameManager.Events.FrameNavigated, frame);
    }
  
    /**
     * @param {string} frameId
     * @param {string} url
     */
    _onFrameNavigatedWithinDocument(frameId, url) {
      const frame = this._frames.get(frameId);
      if (!frame)
        return;
      frame._navigatedWithinDocument(url);
      this.emit(FrameManager.Events.FrameNavigatedWithinDocument, frame);
      this.emit(FrameManager.Events.FrameNavigated, frame);
    }
  
    /**
     * @param {string} frameId
     */
    _onFrameDetached(frameId) {
      const frame = this._frames.get(frameId);
      if (frame)
        this._removeFramesRecursively(frame);
    }
  
    _onExecutionContextCreated(contextPayload) {
      const frameId = contextPayload.auxData && contextPayload.auxData.isDefault ? contextPayload.auxData.frameId : null;
      const frame = frameId ? this._frames.get(frameId) : null;
      const context = new ExecutionContext(this._client, contextPayload, this.createJSHandle.bind(this, contextPayload.id), frame);
      this._contextIdToContext.set(contextPayload.id, context);
      if (frame)
        frame._setDefaultContext(context);
    }
  
    /**
     * @param {!ExecutionContext} context
     */
    _removeContext(context) {
      if (context.frame())
        context.frame()._setDefaultContext(null);
    }
  
    /**
     * @param {number} executionContextId
     */
    _onExecutionContextDestroyed(executionContextId) {
      const context = this._contextIdToContext.get(executionContextId);
      if (!context)
        return;
      this._contextIdToContext.delete(executionContextId);
      this._removeContext(context);
    }
  
    _onExecutionContextsCleared() {
      for (const context of this._contextIdToContext.values())
        this._removeContext(context);
      this._contextIdToContext.clear();
    }
  
    /**
     * @param {number} contextId
     * @param {!Protocol.Runtime.RemoteObject} remoteObject
     * @return {!JSHandle}
     */
    createJSHandle(contextId, remoteObject) {
      const context = this._contextIdToContext.get(contextId);
      assert(context, 'INTERNAL ERROR: missing context with id = ' + contextId);
      if (remoteObject.subtype === 'node')
        return new ElementHandle(context, this._client, remoteObject, this._page, this);
      return new JSHandle(context, this._client, remoteObject);
    }
  
    /**
     * @param {!Frame} frame
     */
    _removeFramesRecursively(frame) {
      for (const child of frame.childFrames())
        this._removeFramesRecursively(child);
      frame._detach();
      this._frames.delete(frame._id);
      this.emit(FrameManager.Events.FrameDetached, frame);
    }
  }
  
  /** @enum {string} */
  FrameManager.Events = {
    FrameAttached: 'frameattached',
    FrameNavigated: 'framenavigated',
    FrameDetached: 'framedetached',
    LifecycleEvent: 'lifecycleevent',
    FrameNavigatedWithinDocument: 'framenavigatedwithindocument'
  };
  
  /**
   * @unrestricted
   */
  class Frame {
    /**
     * @param {!Puppeteer.CDPSession} client
     * @param {?Frame} parentFrame
     * @param {string} frameId
     */
    constructor(client, parentFrame, frameId) {
      this._client = client;
      this._parentFrame = parentFrame;
      this._url = '';
      this._id = frameId;
  
      /** @type {?Promise<!ElementHandle>} */
      this._documentPromise = null;
      /** @type {?Promise<!ExecutionContext>} */
      this._contextPromise = null;
      this._contextResolveCallback = null;
      this._setDefaultContext(null);
  
      /** @type {!Set<!WaitTask>} */
      this._waitTasks = new Set();
      this._loaderId = '';
      /** @type {!Set<string>} */
      this._lifecycleEvents = new Set();
  
      /** @type {!Set<!Frame>} */
      this._childFrames = new Set();
      if (this._parentFrame)
        this._parentFrame._childFrames.add(this);
    }
  
    /**
     * @param {?ExecutionContext} context
     */
    _setDefaultContext(context) {
      if (context) {
        this._contextResolveCallback.call(null, context);
        this._contextResolveCallback = null;
        for (const waitTask of this._waitTasks)
          waitTask.rerun();
      } else {
        this._documentPromise = null;
        this._contextPromise = new Promise(fulfill => {
          this._contextResolveCallback = fulfill;
        });
      }
    }
  
    /**
     * @return {!Promise<!ExecutionContext>}
     */
    executionContext() {
      return this._contextPromise;
    }
  
    /**
     * @param {function()|string} pageFunction
     * @param {!Array<*>} args
     * @return {!Promise<!Puppeteer.JSHandle>}
     */
    async evaluateHandle(pageFunction, ...args) {
      const context = await this._contextPromise;
      return context.evaluateHandle(pageFunction, ...args);
    }
  
    /**
     * @param {Function|string} pageFunction
     * @param {!Array<*>} args
     * @return {!Promise<*>}
     */
    async evaluate(pageFunction, ...args) {
      const context = await this._contextPromise;
      return context.evaluate(pageFunction, ...args);
    }
  
    /**
     * @param {string} selector
     * @return {!Promise<?ElementHandle>}
     */
    async $(selector) {
      const document = await this._document();
      const value = await document.$(selector);
      return value;
    }
  
    /**
     * @return {!Promise<!ElementHandle>}
     */
    async _document() {
      if (this._documentPromise)
        return this._documentPromise;
      this._documentPromise = this._contextPromise.then(async context => {
        const document = await context.evaluateHandle('document');
        return document.asElement();
      });
      return this._documentPromise;
    }
  
    /**
     * @param {string} expression
     * @return {!Promise<!Array<!ElementHandle>>}
     */
    async $x(expression) {
      const document = await this._document();
      const value = await document.$x(expression);
      return value;
    }
  
    /**
     * @param {string} selector
     * @param {Function|string} pageFunction
     * @param {!Array<*>} args
     * @return {!Promise<(!Object|undefined)>}
     */
    async $eval(selector, pageFunction, ...args) {
      const document = await this._document();
      return document.$eval(selector, pageFunction, ...args);
    }
  
    /**
     * @param {string} selector
     * @param {Function|string} pageFunction
     * @param {!Array<*>} args
     * @return {!Promise<(!Object|undefined)>}
     */
    async $$eval(selector, pageFunction, ...args) {
      const document = await this._document();
      const value = await document.$$eval(selector, pageFunction, ...args);
      return value;
    }
  
    /**
     * @param {string} selector
     * @return {!Promise<!Array<!ElementHandle>>}
     */
    async $$(selector) {
      const document = await this._document();
      const value = await document.$$(selector);
      return value;
    }
  
    /**
     * @return {!Promise<String>}
     */
    async content() {
      return await this.evaluate(() => {
        let retVal = '';
        if (document.doctype)
          retVal = new XMLSerializer().serializeToString(document.doctype);
        if (document.documentElement)
          retVal += document.documentElement.outerHTML;
        return retVal;
      });
    }
  
    /**
     * @param {string} html
     */
    async setContent(html) {
      await this.evaluate(html => {
        document.open();
        document.write(html);
        document.close();
      }, html);
    }
  
    /**
     * @return {string}
     */
    name() {
      return this._name || '';
    }
  
    /**
     * @return {string}
     */
    url() {
      return this._url;
    }
  
    /**
     * @return {?Frame}
     */
    parentFrame() {
      return this._parentFrame;
    }
  
    /**
     * @return {!Array.<!Frame>}
     */
    childFrames() {
      return Array.from(this._childFrames);
    }
  
    /**
     * @return {boolean}
     */
    isDetached() {
      return this._detached;
    }
  
    /**
     * @param {Object} options
     * @return {!Promise<!ElementHandle>}
     */
    async addScriptTag(options) {
      if (typeof options.url === 'string') {
        const url = options.url;
        try {
          const context = await this._contextPromise;
          return (await context.evaluateHandle(addScriptUrl, url, options.type)).asElement();
        } catch (error) {
          throw new Error(`Loading script from ${url} failed`);
        }
      }
  
      if (typeof options.path === 'string') {
        let contents = await readFileAsync(options.path, 'utf8');
        contents += '//# sourceURL=' + options.path.replace(/\n/g, '');
        const context = await this._contextPromise;
        return (await context.evaluateHandle(addScriptContent, contents, options.type)).asElement();
      }
  
      if (typeof options.content === 'string') {
        const context = await this._contextPromise;
        return (await context.evaluateHandle(addScriptContent, options.content, options.type)).asElement();
      }
  
      throw new Error('Provide an object with a `url`, `path` or `content` property');
  
      /**
       * @param {string} url
       * @param {string} type
       * @return {!Promise<!HTMLElement>}
       */
      async function addScriptUrl(url, type) {
        const script = document.createElement('script');
        script.src = url;
        if (type)
          script.type = type;
        const promise = new Promise((res, rej) => {
          script.onload = res;
          script.onerror = rej;
        });
        document.head.appendChild(script);
        await promise;
        return script;
      }
  
      /**
       * @param {string} content
       * @param {string} type
       * @return {!HTMLElement}
       */
      function addScriptContent(content, type = 'text/javascript') {
        const script = document.createElement('script');
        script.type = type;
        script.text = content;
        let error = null;
        script.onerror = e => error = e;
        document.head.appendChild(script);
        if (error)
          throw error;
        return script;
      }
    }
  
    /**
     * @param {Object} options
     * @return {!Promise<!ElementHandle>}
     */
    async addStyleTag(options) {
      if (typeof options.url === 'string') {
        const url = options.url;
        try {
          const context = await this._contextPromise;
          return (await context.evaluateHandle(addStyleUrl, url)).asElement();
        } catch (error) {
          throw new Error(`Loading style from ${url} failed`);
        }
      }
  
      if (typeof options.path === 'string') {
        let contents = await readFileAsync(options.path, 'utf8');
        contents += '/*# sourceURL=' + options.path.replace(/\n/g, '') + '*/';
        const context = await this._contextPromise;
        return (await context.evaluateHandle(addStyleContent, contents)).asElement();
      }
  
      if (typeof options.content === 'string') {
        const context = await this._contextPromise;
        return (await context.evaluateHandle(addStyleContent, options.content)).asElement();
      }
  
      throw new Error('Provide an object with a `url`, `path` or `content` property');
  
      /**
       * @param {string} url
       * @return {!Promise<!HTMLElement>}
       */
      async function addStyleUrl(url) {
        const link = document.createElement('link');
        link.rel = 'stylesheet';
        link.href = url;
        const promise = new Promise((res, rej) => {
          link.onload = res;
          link.onerror = rej;
        });
        document.head.appendChild(link);
        await promise;
        return link;
      }
  
      /**
       * @param {string} content
       * @return {!Promise<!HTMLElement>}
       */
      async function addStyleContent(content) {
        const style = document.createElement('style');
        style.type = 'text/css';
        style.appendChild(document.createTextNode(content));
        const promise = new Promise((res, rej) => {
          style.onload = res;
          style.onerror = rej;
        });
        document.head.appendChild(style);
        await promise;
        return style;
      }
    }
  
    /**
     * @param {string} selector
     * @param {!Object=} options
     */
    async click(selector, options = {}) {
      const handle = await this.$(selector);
      assert(handle, 'No node found for selector: ' + selector);
      await handle.click(options);
      await handle.dispose();
    }
  
    /**
     * @param {string} selector
     */
    async focus(selector) {
      const handle = await this.$(selector);
      assert(handle, 'No node found for selector: ' + selector);
      await handle.focus();
      await handle.dispose();
    }
  
    /**
     * @param {string} selector
     */
    async hover(selector) {
      const handle = await this.$(selector);
      assert(handle, 'No node found for selector: ' + selector);
      await handle.hover();
      await handle.dispose();
    }
  
    /**
    * @param {string} selector
    * @param {!Array<string>} values
    * @return {!Promise<!Array<string>>}
    */
    select(selector, ...values){
      for (const value of values)
        assert(helper.isString(value), 'Values must be strings. Found value "' + value + '" of type "' + (typeof value) + '"');
      return this.$eval(selector, (element, values) => {
        if (element.nodeName.toLowerCase() !== 'select')
          throw new Error('Element is not a <select> element.');
  
        const options = Array.from(element.options);
        element.value = undefined;
        for (const option of options) {
          option.selected = values.includes(option.value);
          if (option.selected && !element.multiple)
            break;
        }
        element.dispatchEvent(new Event('input', { 'bubbles': true }));
        element.dispatchEvent(new Event('change', { 'bubbles': true }));
        return options.filter(option => option.selected).map(option => option.value);
      }, values);
    }
  
    /**
     * @param {string} selector
     */
    async tap(selector) {
      const handle = await this.$(selector);
      assert(handle, 'No node found for selector: ' + selector);
      await handle.tap();
      await handle.dispose();
    }
  
    /**
     * @param {string} selector
     * @param {string} text
     * @param {{delay: (number|undefined)}=} options
     */
    async type(selector, text, options) {
      const handle = await this.$(selector);
      assert(handle, 'No node found for selector: ' + selector);
      await handle.type(text, options);
      await handle.dispose();
    }
  
    /**
     * @param {(string|number|Function)} selectorOrFunctionOrTimeout
     * @param {!Object=} options
     * @param {!Array<*>} args
     * @return {!Promise}
     */
    waitFor(selectorOrFunctionOrTimeout, options = {}, ...args) {
      const xPathPattern = '//';
  
      if (helper.isString(selectorOrFunctionOrTimeout)) {
        const string = /** @type {string} */ (selectorOrFunctionOrTimeout);
        if (string.startsWith(xPathPattern))
          return this.waitForXPath(string, options);
        return this.waitForSelector(string, options);
      }
      if (helper.isNumber(selectorOrFunctionOrTimeout))
        return new Promise(fulfill => setTimeout(fulfill, selectorOrFunctionOrTimeout));
      if (typeof selectorOrFunctionOrTimeout === 'function')
        return this.waitForFunction(selectorOrFunctionOrTimeout, options, ...args);
      return Promise.reject(new Error('Unsupported target type: ' + (typeof selectorOrFunctionOrTimeout)));
    }
  
    /**
     * @param {string} selector
     * @param {!Object=} options
     * @return {!Promise}
     */
    waitForSelector(selector, options = {}) {
      return this._waitForSelectorOrXPath(selector, false, options);
    }
  
    /**
     * @param {string} xpath
     * @param {!Object=} options
     * @return {!Promise}
     */
    waitForXPath(xpath, options = {}) {
      return this._waitForSelectorOrXPath(xpath, true, options);
    }
  
    /**
     * @param {Function|string} pageFunction
     * @param {!Object=} options
     * @return {!Promise}
     */
    waitForFunction(pageFunction, options = {}, ...args) {
      const timeout = helper.isNumber(options.timeout) ? options.timeout : 30000;
      const polling = options.polling || 'raf';
      return new WaitTask(this, pageFunction, 'function', polling, timeout, ...args).promise;
    }
  
    /**
     * @return {!Promise<string>}
     */
    async title() {
      return this.evaluate(() => document.title);
    }
  
    /**
     * @param {string} selectorOrXPath
     * @param {boolean} isXPath
     * @param {!Object=} options
     * @return {!Promise}
     */
    _waitForSelectorOrXPath(selectorOrXPath, isXPath, options = {}) {
      const waitForVisible = !!options.visible;
      const waitForHidden = !!options.hidden;
      const polling = waitForVisible || waitForHidden ? 'raf' : 'mutation';
      const timeout = helper.isNumber(options.timeout) ? options.timeout : 30000;
      return new WaitTask(this, predicate, `${isXPath ? 'XPath' : 'selector'} "${selectorOrXPath}"`, polling, timeout, selectorOrXPath, isXPath, waitForVisible, waitForHidden).promise;
  
      /**
       * @param {string} selectorOrXPath
       * @param {boolean} isXPath
       * @param {boolean} waitForVisible
       * @param {boolean} waitForHidden
       * @return {?Node|boolean}
       */
      function predicate(selectorOrXPath, isXPath, waitForVisible, waitForHidden) {
        const node = isXPath
          ? document.evaluate(selectorOrXPath, document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue
          : document.querySelector(selectorOrXPath);
        if (!node)
          return waitForHidden;
        if (!waitForVisible && !waitForHidden)
          return node;
        const element = /** @type {Element} */ (node.nodeType === Node.TEXT_NODE ? node.parentElement : node);
  
        const style = window.getComputedStyle(element);
        const isVisible = style && style.visibility !== 'hidden' && hasVisibleBoundingBox();
        const success = (waitForVisible === isVisible || waitForHidden === !isVisible);
        return success ? node : null;
  
        /**
         * @return {boolean}
         */
        function hasVisibleBoundingBox() {
          const rect = element.getBoundingClientRect();
          return !!(rect.top || rect.bottom || rect.width || rect.height);
        }
      }
    }
  
    /**
     * @param {!Protocol.Page.Frame} framePayload
     */
    _navigated(framePayload) {
      this._name = framePayload.name;
      // TODO(lushnikov): remove this once requestInterception has loaderId exposed.
      this._navigationURL = framePayload.url;
      this._url = framePayload.url;
    }
  
    /**
     * @param {string} url
     */
    _navigatedWithinDocument(url) {
      this._url = url;
    }
  
    /**
     * @param {string} loaderId
     * @param {string} name
     */
    _onLifecycleEvent(loaderId, name) {
      if (name === 'init') {
        this._loaderId = loaderId;
        this._lifecycleEvents.clear();
      }
      this._lifecycleEvents.add(name);
    }
  
    _onLoadingStopped() {
      this._lifecycleEvents.add('DOMContentLoaded');
      this._lifecycleEvents.add('load');
    }
  
    _detach() {
      for (const waitTask of this._waitTasks)
        waitTask.terminate(new Error('waitForFunction failed: frame got detached.'));
      this._detached = true;
      if (this._parentFrame)
        this._parentFrame._childFrames.delete(this);
      this._parentFrame = null;
    }
  }
  helper.tracePublicAPI(Frame);
  
  class WaitTask {
    /**
     * @param {!Frame} frame
     * @param {Function|string} predicateBody
     * @param {string|number} polling
     * @param {number} timeout
     * @param {!Array<*>} args
     */
    constructor(frame, predicateBody, title, polling, timeout, ...args) {
      if (helper.isString(polling))
        assert(polling === 'raf' || polling === 'mutation', 'Unknown polling option: ' + polling);
      else if (helper.isNumber(polling))
        assert(polling > 0, 'Cannot poll with non-positive interval: ' + polling);
      else
        throw new Error('Unknown polling options: ' + polling);
  
      this._frame = frame;
      this._polling = polling;
      this._timeout = timeout;
      this._predicateBody = helper.isString(predicateBody) ? 'return ' + predicateBody : 'return (' + predicateBody + ')(...args)';
      this._args = args;
      this._runCount = 0;
      frame._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 Error(`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 {?JSHandle} */
      let success = null;
      let error = null;
      try {
        success = await (await this._frame.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._frame.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._frame._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 = {FrameManager, Frame};
  