playwright/src/page.ts

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/**
* Copyright 2017 Google Inc. All rights reserved.
* Modifications copyright (c) Microsoft Corporation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import * as dom from './dom';
import * as frames from './frames';
import { assert, debugError, helper } from './helper';
import * as input from './input';
import * as js from './javascript';
import * as network from './network';
import { Screenshotter } from './screenshotter';
import { TimeoutSettings } from './timeoutSettings';
import * as types from './types';
import { Events } from './events';
import { BrowserContext } from './browserContext';
import { ConsoleMessage, ConsoleMessageLocation } from './console';
import * as accessibility from './accessibility';
import * as platform from './platform';
export interface PageDelegate {
readonly rawMouse: input.RawMouse;
readonly rawKeyboard: input.RawKeyboard;
opener(): Promise<Page | null>;
reload(): Promise<void>;
goBack(): Promise<boolean>;
goForward(): Promise<boolean>;
exposeBinding(binding: PageBinding): Promise<void>;
evaluateOnNewDocument(source: string): Promise<void>;
closePage(runBeforeUnload: boolean): Promise<void>;
navigateFrame(frame: frames.Frame, url: string, referrer: string | undefined): Promise<frames.GotoResult>;
updateExtraHTTPHeaders(): Promise<void>;
setViewportSize(viewportSize: types.Size): Promise<void>;
setEmulateMedia(mediaType: types.MediaType | null, colorScheme: types.ColorScheme | null): Promise<void>;
setCacheEnabled(enabled: boolean): Promise<void>;
setRequestInterception(enabled: boolean): Promise<void>;
setOfflineMode(enabled: boolean): Promise<void>;
authenticate(credentials: types.Credentials | null): Promise<void>;
setFileChooserIntercepted(enabled: boolean): Promise<void>;
canScreenshotOutsideViewport(): boolean;
resetViewport(): Promise<void>; // Only called if canScreenshotOutsideViewport() returns false.
setBackgroundColor(color?: { r: number; g: number; b: number; a: number; }): Promise<void>;
takeScreenshot(format: string, documentRect: types.Rect | undefined, viewportRect: types.Rect | undefined, quality: number | undefined): Promise<platform.BufferType>;
isElementHandle(remoteObject: any): boolean;
adoptElementHandle<T extends Node>(handle: dom.ElementHandle<T>, to: dom.FrameExecutionContext): Promise<dom.ElementHandle<T>>;
getContentFrame(handle: dom.ElementHandle): Promise<frames.Frame | null>; // Only called for frame owner elements.
getOwnerFrame(handle: dom.ElementHandle): Promise<string | null>; // Returns frameId.
getContentQuads(handle: dom.ElementHandle): Promise<types.Quad[] | null>;
layoutViewport(): Promise<{ width: number, height: number }>;
setInputFiles(handle: dom.ElementHandle<HTMLInputElement>, files: types.FilePayload[]): Promise<void>;
getBoundingBox(handle: dom.ElementHandle): Promise<types.Rect | null>;
getFrameElement(frame: frames.Frame): Promise<dom.ElementHandle>;
scrollRectIntoViewIfNeeded(handle: dom.ElementHandle, rect?: types.Rect): Promise<void>;
getAccessibilityTree(needle?: dom.ElementHandle): Promise<{tree: accessibility.AXNode, needle: accessibility.AXNode | null}>;
pdf?: (options?: types.PDFOptions) => Promise<platform.BufferType>;
coverage?: () => any;
}
type PageState = {
viewportSize: types.Size | null;
mediaType: types.MediaType | null;
colorScheme: types.ColorScheme | null;
extraHTTPHeaders: network.Headers | null;
cacheEnabled: boolean | null;
interceptNetwork: boolean | null;
offlineMode: boolean | null;
credentials: types.Credentials | null;
hasTouch: boolean | null;
};
export type FileChooser = {
element: dom.ElementHandle,
multiple: boolean
};
export class PageEvent {
private readonly _page: Page;
constructor(page: Page) {
this._page = page;
}
async page(/* options?: frames.NavigateOptions */): Promise<Page> {
return this._page;
}
}
export class Page extends platform.EventEmitter {
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private _closed = false;
private _closedCallback: () => void;
private _closedPromise: Promise<void>;
private _disconnected = false;
private _disconnectedCallback: (e: Error) => void;
readonly _disconnectedPromise: Promise<Error>;
private _browserContext: BrowserContext;
readonly keyboard: input.Keyboard;
readonly mouse: input.Mouse;
readonly _timeoutSettings: TimeoutSettings;
readonly _delegate: PageDelegate;
readonly _state: PageState;
readonly _pageBindings = new Map<string, PageBinding>();
readonly _screenshotter: Screenshotter;
readonly _frameManager: frames.FrameManager;
readonly accessibility: accessibility.Accessibility;
private _workers = new Map<string, Worker>();
readonly pdf: ((options?: types.PDFOptions) => Promise<platform.BufferType>) | undefined;
readonly coverage: any;
readonly _requestHandlers: { url: types.URLMatch, handler: (request: network.Request) => void }[] = [];
_ownedContext: BrowserContext | undefined;
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constructor(delegate: PageDelegate, browserContext: BrowserContext) {
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super();
this._delegate = delegate;
this._closedCallback = () => {};
this._closedPromise = new Promise(f => this._closedCallback = f);
this._disconnectedCallback = () => {};
this._disconnectedPromise = new Promise(f => this._disconnectedCallback = f);
this._browserContext = browserContext;
let viewportSize: types.Size | null = null;
if (browserContext._options.viewport) {
viewportSize = {
width: browserContext._options.viewport.width,
height: browserContext._options.viewport.height,
};
}
this._state = {
viewportSize,
mediaType: null,
colorScheme: null,
extraHTTPHeaders: null,
cacheEnabled: null,
interceptNetwork: null,
offlineMode: null,
credentials: null,
hasTouch: null,
};
this.accessibility = new accessibility.Accessibility(delegate.getAccessibilityTree.bind(delegate));
this.keyboard = new input.Keyboard(delegate.rawKeyboard);
this.mouse = new input.Mouse(delegate.rawMouse, this.keyboard);
this._timeoutSettings = new TimeoutSettings(browserContext._timeoutSettings);
this._screenshotter = new Screenshotter(this);
this._frameManager = new frames.FrameManager(this);
if (delegate.pdf)
this.pdf = delegate.pdf.bind(delegate);
this.coverage = delegate.coverage ? delegate.coverage() : null;
}
_didClose() {
assert(!this._closed, 'Page closed twice');
this._closed = true;
this.emit(Events.Page.Close);
this._closedCallback();
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}
_didCrash() {
const error = new Error('Page crashed!');
// Do not report node.js stack.
error.stack = 'Error: ' + error.message; // Stack is supposed to contain error message as the first line.
this.emit('error', error);
}
_didDisconnect() {
assert(!this._disconnected, 'Page disconnected twice');
this._disconnected = true;
this._disconnectedCallback(new Error('Target closed'));
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}
async _onFileChooserOpened(handle: dom.ElementHandle) {
const multiple = await handle.evaluate(element => !!(element as HTMLInputElement).multiple);
if (!this.listenerCount(Events.Page.FileChooser)) {
await handle.dispose();
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return;
}
const fileChooser: FileChooser = { element: handle, multiple };
this.emit(Events.Page.FileChooser, fileChooser);
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}
context(): BrowserContext {
return this._browserContext;
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}
async opener(): Promise<Page | null> {
return await this._delegate.opener();
}
mainFrame(): frames.Frame {
return this._frameManager.mainFrame();
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}
frame(options: { name?: string, url?: types.URLMatch }): frames.Frame | null {
assert(options.name || options.url, 'Either name or url matcher should be specified');
return this.frames().find(f => {
if (options.name)
return f.name() === options.name;
return platform.urlMatches(f.url(), options.url);
}) || null;
}
frames(): frames.Frame[] {
return this._frameManager.frames();
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}
setDefaultNavigationTimeout(timeout: number) {
this._timeoutSettings.setDefaultNavigationTimeout(timeout);
}
setDefaultTimeout(timeout: number) {
this._timeoutSettings.setDefaultTimeout(timeout);
}
async $(selector: string): Promise<dom.ElementHandle<Element> | null> {
return this.mainFrame().$(selector);
}
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async waitForSelector(selector: string, options?: types.TimeoutOptions & { visibility?: types.Visibility }): Promise<dom.ElementHandle<Element> | null> {
return this.mainFrame().waitForSelector(selector, options);
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}
async $wait(selector: string, options?: types.TimeoutOptions & { visibility?: types.Visibility }): Promise<dom.ElementHandle<Element> | null> {
return this.mainFrame().$wait(selector, options);
}
evaluateHandle: types.EvaluateHandle = async (pageFunction, ...args) => {
return this.mainFrame().evaluateHandle(pageFunction, ...args as any);
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}
$eval: types.$Eval = async (selector, pageFunction, ...args) => {
return this.mainFrame().$eval(selector, pageFunction, ...args as any);
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}
$$eval: types.$$Eval = async (selector, pageFunction, ...args) => {
return this.mainFrame().$$eval(selector, pageFunction, ...args as any);
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}
async $$(selector: string): Promise<dom.ElementHandle<Element>[]> {
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return this.mainFrame().$$(selector);
}
async addScriptTag(options: { url?: string; path?: string; content?: string; type?: string; }): Promise<dom.ElementHandle> {
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return this.mainFrame().addScriptTag(options);
}
async addStyleTag(options: { url?: string; path?: string; content?: string; }): Promise<dom.ElementHandle> {
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return this.mainFrame().addStyleTag(options);
}
async exposeFunction(name: string, playwrightFunction: Function) {
if (this._pageBindings.has(name))
throw new Error(`Function "${name}" has been already registered`);
if (this._browserContext._pageBindings.has(name))
throw new Error(`Function "${name}" has been already registered in the browser context`);
const binding = new PageBinding(name, playwrightFunction);
this._pageBindings.set(name, binding);
await this._delegate.exposeBinding(binding);
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}
setExtraHTTPHeaders(headers: network.Headers) {
this._state.extraHTTPHeaders = network.verifyHeaders(headers);
return this._delegate.updateExtraHTTPHeaders();
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}
async _onBindingCalled(payload: string, context: js.ExecutionContext) {
await PageBinding.dispatch(this, payload, context);
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}
_addConsoleMessage(type: string, args: js.JSHandle[], location: ConsoleMessageLocation, text?: string) {
const message = new ConsoleMessage(type, text, args, location);
const intercepted = this._frameManager.interceptConsoleMessage(message);
if (intercepted || !this.listenerCount(Events.Page.Console))
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args.forEach(arg => arg.dispose());
else
this.emit(Events.Page.Console, message);
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}
url(): string {
return this.mainFrame().url();
}
async content(): Promise<string> {
return this.mainFrame().content();
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}
async setContent(html: string, options?: frames.NavigateOptions): Promise<void> {
return this.mainFrame().setContent(html, options);
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}
async goto(url: string, options?: frames.GotoOptions): Promise<network.Response | null> {
return this.mainFrame().goto(url, options);
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}
async reload(options?: frames.NavigateOptions): Promise<network.Response | null> {
const waitPromise = this.waitForNavigation(options);
await this._delegate.reload();
return waitPromise;
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}
async waitForNavigation(options?: frames.WaitForNavigationOptions): Promise<network.Response | null> {
return this.mainFrame().waitForNavigation(options);
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}
async waitForLoadState(options?: frames.NavigateOptions): Promise<void> {
return this.mainFrame().waitForLoadState(options);
}
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async waitForEvent(event: string, optionsOrPredicate: Function | (types.TimeoutOptions & { predicate?: Function }) = {}): Promise<any> {
if (typeof optionsOrPredicate === 'function')
optionsOrPredicate = { predicate: optionsOrPredicate };
const { timeout = this._timeoutSettings.timeout(), predicate = () => true } = optionsOrPredicate;
return helper.waitForEvent(this, event, (...args: any[]) => !!predicate(...args), timeout, this._disconnectedPromise);
}
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async waitForRequest(urlOrPredicate: string | RegExp | ((r: network.Request) => boolean), options: types.TimeoutOptions = {}): Promise<network.Request> {
const { timeout = this._timeoutSettings.timeout() } = options;
return helper.waitForEvent(this, Events.Page.Request, (request: network.Request) => {
if (helper.isString(urlOrPredicate) || helper.isRegExp(urlOrPredicate))
return platform.urlMatches(request.url(), urlOrPredicate);
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return urlOrPredicate(request);
}, timeout, this._disconnectedPromise);
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}
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async waitForResponse(urlOrPredicate: string | RegExp | ((r: network.Response) => boolean), options: types.TimeoutOptions = {}): Promise<network.Response> {
const { timeout = this._timeoutSettings.timeout() } = options;
return helper.waitForEvent(this, Events.Page.Response, (response: network.Response) => {
if (helper.isString(urlOrPredicate) || helper.isRegExp(urlOrPredicate))
return platform.urlMatches(response.url(), urlOrPredicate);
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return urlOrPredicate(response);
}, timeout, this._disconnectedPromise);
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}
async goBack(options?: frames.NavigateOptions): Promise<network.Response | null> {
const waitPromise = this.waitForNavigation(options);
const result = await this._delegate.goBack();
if (!result) {
waitPromise.catch(() => {});
return null;
}
return waitPromise;
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}
async goForward(options?: frames.NavigateOptions): Promise<network.Response | null> {
const waitPromise = this.waitForNavigation(options);
const result = await this._delegate.goForward();
if (!result) {
waitPromise.catch(() => {});
return null;
}
return waitPromise;
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}
async emulateMedia(options: { media?: types.MediaType, colorScheme?: types.ColorScheme }) {
assert(!options.media || types.mediaTypes.has(options.media), 'Unsupported media: ' + options.media);
assert(!options.colorScheme || types.colorSchemes.has(options.colorScheme), 'Unsupported color scheme: ' + options.colorScheme);
if (options.media !== undefined)
this._state.mediaType = options.media;
if (options.colorScheme !== undefined)
this._state.colorScheme = options.colorScheme;
await this._delegate.setEmulateMedia(this._state.mediaType, this._state.colorScheme);
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}
async setViewportSize(viewportSize: types.Size) {
this._state.viewportSize = { ...viewportSize };
await this._delegate.setViewportSize(this._state.viewportSize);
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}
viewportSize(): types.Size | null {
return this._state.viewportSize;
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}
evaluate: types.Evaluate = async (pageFunction, ...args) => {
return this.mainFrame().evaluate(pageFunction, ...args as any);
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}
async addInitScript(script: Function | string | { path?: string, content?: string }, ...args: any[]) {
await this._delegate.evaluateOnNewDocument(await helper.evaluationScript(script, args));
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}
async setCacheEnabled(enabled: boolean = true) {
if (this._state.cacheEnabled === enabled)
return;
this._state.cacheEnabled = enabled;
await this._delegate.setCacheEnabled(enabled);
}
async route(url: types.URLMatch, handler: (request: network.Request) => void) {
if (!this._state.interceptNetwork) {
this._state.interceptNetwork = true;
await this._delegate.setRequestInterception(true);
}
this._requestHandlers.push({ url, handler });
}
_requestStarted(request: network.Request) {
this.emit(Events.Page.Request, request);
if (!request._isIntercepted())
return;
for (const { url, handler } of this._requestHandlers) {
if (platform.urlMatches(request.url(), url)) {
handler(request);
return;
}
}
request.continue();
}
async setOfflineMode(enabled: boolean) {
if (this._state.offlineMode === enabled)
return;
this._state.offlineMode = enabled;
await this._delegate.setOfflineMode(enabled);
}
async authenticate(credentials: types.Credentials | null) {
this._state.credentials = credentials;
await this._delegate.authenticate(credentials);
}
async screenshot(options?: types.ScreenshotOptions): Promise<platform.BufferType> {
return this._screenshotter.screenshotPage(options);
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}
async title(): Promise<string> {
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return this.mainFrame().title();
}
async close(options: { runBeforeUnload: (boolean | undefined); } = {runBeforeUnload: undefined}) {
if (this._closed)
return;
assert(!this._disconnected, 'Protocol error: Connection closed. Most likely the page has been closed.');
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const runBeforeUnload = !!options.runBeforeUnload;
await this._delegate.closePage(runBeforeUnload);
if (!runBeforeUnload)
await this._closedPromise;
if (this._ownedContext)
await this._ownedContext.close();
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}
isClosed(): boolean {
return this._closed;
}
async click(selector: string, options?: dom.ClickOptions & types.WaitForOptions) {
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return this.mainFrame().click(selector, options);
}
async dblclick(selector: string, options?: dom.MultiClickOptions & types.WaitForOptions) {
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return this.mainFrame().dblclick(selector, options);
}
async tripleclick(selector: string, options?: dom.MultiClickOptions & types.WaitForOptions) {
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return this.mainFrame().tripleclick(selector, options);
}
async fill(selector: string, value: string, options?: types.WaitForOptions) {
return this.mainFrame().fill(selector, value, options);
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}
async focus(selector: string, options?: types.WaitForOptions) {
return this.mainFrame().focus(selector, options);
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}
async hover(selector: string, options?: dom.PointerActionOptions & types.WaitForOptions) {
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return this.mainFrame().hover(selector, options);
}
async select(selector: string, value: string | dom.ElementHandle | types.SelectOption | string[] | dom.ElementHandle[] | types.SelectOption[], options?: types.WaitForOptions): Promise<string[]> {
return this.mainFrame().select(selector, value, options);
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}
async type(selector: string, text: string, options?: { delay?: number } & types.WaitForOptions) {
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return this.mainFrame().type(selector, text, options);
}
async check(selector: string, options?: types.WaitForOptions) {
return this.mainFrame().check(selector, options);
}
async uncheck(selector: string, options?: types.WaitForOptions) {
return this.mainFrame().uncheck(selector, options);
}
async waitFor(selectorOrFunctionOrTimeout: (string | number | Function), options?: types.WaitForFunctionOptions & { visibility?: types.Visibility }, ...args: any[]): Promise<js.JSHandle | null> {
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return this.mainFrame().waitFor(selectorOrFunctionOrTimeout, options, ...args);
}
async waitForFunction(pageFunction: Function | string, options?: types.WaitForFunctionOptions, ...args: any[]): Promise<js.JSHandle> {
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return this.mainFrame().waitForFunction(pageFunction, options, ...args);
}
workers(): Worker[] {
return [...this._workers.values()];
}
_addWorker(workerId: string, worker: Worker) {
this._workers.set(workerId, worker);
this.emit(Events.Page.Worker, worker);
}
_removeWorker(workerId: string) {
const worker = this._workers.get(workerId);
if (!worker)
return;
worker.emit(Events.Worker.Close, worker);
this._workers.delete(workerId);
}
_clearWorkers() {
for (const [workerId, worker] of this._workers) {
worker.emit(Events.Worker.Close, worker);
this._workers.delete(workerId);
}
}
on(event: string | symbol, listener: platform.Listener): this {
if (event === Events.Page.FileChooser) {
if (!this.listenerCount(event))
this._delegate.setFileChooserIntercepted(true);
}
super.on(event, listener);
return this;
}
removeListener(event: string | symbol, listener: platform.Listener): this {
super.removeListener(event, listener);
if (event === Events.Page.FileChooser && !this.listenerCount(event))
this._delegate.setFileChooserIntercepted(false);
return this;
}
}
export class Worker extends platform.EventEmitter {
private _url: string;
private _executionContextPromise: Promise<js.ExecutionContext>;
private _executionContextCallback: (value?: js.ExecutionContext) => void;
_existingExecutionContext: js.ExecutionContext | null = null;
constructor(url: string) {
super();
this._url = url;
this._executionContextCallback = () => {};
this._executionContextPromise = new Promise(x => this._executionContextCallback = x);
}
_createExecutionContext(delegate: js.ExecutionContextDelegate) {
this._existingExecutionContext = new js.ExecutionContext(delegate);
this._executionContextCallback(this._existingExecutionContext);
}
url(): string {
return this._url;
}
evaluate: types.Evaluate = async (pageFunction, ...args) => {
return (await this._executionContextPromise).evaluate(pageFunction, ...args as any);
}
evaluateHandle: types.EvaluateHandle = async (pageFunction, ...args) => {
return (await this._executionContextPromise).evaluateHandle(pageFunction, ...args as any);
}
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}
export class PageBinding {
readonly name: string;
readonly playwrightFunction: Function;
readonly source: string;
constructor(name: string, playwrightFunction: Function) {
this.name = name;
this.playwrightFunction = playwrightFunction;
this.source = helper.evaluationString(addPageBinding, name);
}
static async dispatch(page: Page, payload: string, context: js.ExecutionContext) {
const {name, seq, args} = JSON.parse(payload);
let expression = null;
try {
let binding = page._pageBindings.get(name);
if (!binding)
binding = page.context()._pageBindings.get(name);
const result = await binding!.playwrightFunction(...args);
expression = helper.evaluationString(deliverResult, name, seq, result);
} catch (error) {
if (error instanceof Error)
expression = helper.evaluationString(deliverError, name, seq, error.message, error.stack);
else
expression = helper.evaluationString(deliverErrorValue, name, seq, error);
}
context.evaluate(expression).catch(debugError);
function deliverResult(name: string, seq: number, result: any) {
(window as any)[name]['callbacks'].get(seq).resolve(result);
(window as any)[name]['callbacks'].delete(seq);
}
function deliverError(name: string, seq: number, message: string, stack: string) {
const error = new Error(message);
error.stack = stack;
(window as any)[name]['callbacks'].get(seq).reject(error);
(window as any)[name]['callbacks'].delete(seq);
}
function deliverErrorValue(name: string, seq: number, value: any) {
(window as any)[name]['callbacks'].get(seq).reject(value);
(window as any)[name]['callbacks'].delete(seq);
}
}
}
function addPageBinding(bindingName: string) {
const binding = (window as any)[bindingName];
(window as any)[bindingName] = (...args: any[]) => {
const me = (window as any)[bindingName];
let callbacks = me['callbacks'];
if (!callbacks) {
callbacks = new Map();
me['callbacks'] = callbacks;
}
const seq = (me['lastSeq'] || 0) + 1;
me['lastSeq'] = seq;
const promise = new Promise((resolve, reject) => callbacks.set(seq, {resolve, reject}));
binding(JSON.stringify({name: bindingName, seq, args}));
return promise;
};
}