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How to use trapEventForPluginEventSystem method in Playwright Internal

Best JavaScript code snippet using playwright-internal

ReactDOMEventListener.js

...7  function isEnabled() {8    return _enabled;9  }10  function trapBubbledEvent(topLevelType, element) {11    trapEventForPluginEventSystem(element, topLevelType, false);12  }13  function trapCapturedEvent(topLevelType, element) {14    trapEventForPluginEventSystem(element, topLevelType, true);15  }16  function trapEventForPluginEventSystem(container, topLevelType, capture) {17    var listener;18    switch (getEventPriorityForPluginSystem(topLevelType)) {19      case DiscreteEvent:20        listener = dispatchDiscreteEvent.bind(null, topLevelType, PLUGIN_EVENT_SYSTEM, container);21        break;22      case UserBlockingEvent:23        listener = dispatchUserBlockingUpdate.bind(null, topLevelType, PLUGIN_EVENT_SYSTEM, container);24        break;25      case ContinuousEvent:26      default:27        listener = dispatchEvent.bind(null, topLevelType, PLUGIN_EVENT_SYSTEM, container);28        break;29    }30    var rawEventName = getRawEventName(topLevelType);...

Using AI Code Generation

1const { trapEventForPluginEventSystem } = require('playwright');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const context = await browser.newContext();6  const page = await context.newPage();7  const event = await trapEventForPluginEventSystem(page, 'page', 'load');8  console.log(event);9  await browser.close();10})();11const { trapEventForPluginEventSystem } = require('playwright');12const { chromium } = require('playwright');13(async () => {14const browser = await chromium.launch();15const context = await browser.newContext();16const page = await context.newPage();17const event = await trapEventForPluginEventSystem(page, 'page', 'load');18console.log(event);19await browser.close();20})();

Using AI Code Generation

1const { Playwright } = require('playwright');2const { trapEventForPluginEventSystem } = Playwright.internal;3const { Playwright } = require('playwright');4const { trapEventForPluginEventSystem } = Playwright.internal;5const { Playwright } = require('playwright');6const { trapEventForPluginEventSystem } = Playwright.internal;7const { Playwright } = require('playwright');8const { trapEventForPluginEventSystem } = Playwright.internal;9const { Playwright } = require('playwright');10const { trapEventForPluginEventSystem } = Playwright.internal;11const { Playwright } = require('playwright');12const { trapEventForPluginEventSystem } = Playwright.internal;13const { Playwright } = require('playwright');14const { trapEventForPluginEventSystem } = Playwright.internal;15const { Playwright } = require('playwright');16const { trapEventForPluginEventSystem } = Playwright.internal;17const { Playwright } = require('playwright');18const { trapEventForPluginEventSystem } = Playwright.internal;19const { Playwright } = require('playwright');20const { trapEventForPluginEventSystem } = Playwright.internal;21const { Playwright } = require('playwright');22const { trapEventForPluginEventSystem } = Playwright.internal;23const { Playwright } = require('playwright');24const { trapEventForPluginEventSystem } = Playwright.internal;

Using AI Code Generation

1const { trapEventForPluginEventSystem } = require('playwright/lib/protocol/protocol.js');2const { Page } = require('playwright/lib/page.js');3const { BrowserContext } = require('playwright/lib/browserContext.js');4const { Browser } = require('playwright/lib/browser.js');5const { BrowserServer } = require('playwright/lib/server/browserServer.js');6const { BrowserType } = require('playwright/lib/server/browserType.js');7const { Playwright } = require('playwright/lib/server/playwright.js');8const { trapEventForPluginEventSystem } = require('playwright/lib/protocol/protocol.js');9const { Page } = require('playwright/lib/page.js');10const { BrowserContext } = require('playwright/lib/browserContext.js');11const { Browser } = require('playwright/lib/browser.js');12const { BrowserServer } = require('playwright/lib/server/browserServer.js');13const { BrowserType } = require('playwright/lib/server/browserType.js');14const { Playwright } = require('playwright/lib/server/playwright.js');15const { trapEventForPluginEventSystem } = require('playwright/lib/protocol/protocol.js');16const { Page } = require('playwright/lib/page.js');17const { BrowserContext } = require('playwright/lib/browserContext.js');18const { Browser } = require('playwright/lib/browser.js');19const { BrowserServer } = require('playwright/lib/server/browserServer.js');20const { BrowserType } = require('playwright/lib/server/browserType.js');21const { Playwright } = require('playwright/lib/server/playwright.js');22const { trapEventForPluginEventSystem } = require('playwright/lib/protocol/protocol.js');23const { Page } = require('playwright/lib/page.js');24const { BrowserContext } = require('playwright/lib/browserContext.js');25const { Browser } = require('playwright/lib/browser.js');26const { BrowserServer } = require('playwright/lib/server/browserServer.js');27const { BrowserType } = require('playwright/lib/server/browserType.js');28const { Playwright } = require('playwright/lib/server/playwright.js');

Using AI Code Generation

1const { test, expect } = require('@playwright/test');2const { trapEventForPluginEventSystem } = require('@playwright/test/lib/server/trace/recorder/plugins');3test('should record events', async ({ page }) => {4  await page.click('input[name="q"]');5  await page.type('input[name="q"]', 'hello');6  await page.click('input[name="btnK"]');7  await page.waitForResponse('**/complete/search**');8  const events = trapEventForPluginEventSystem(page);9  await page.click('text=Images');10  await page.waitForResponse('**/search**');11  expect(events).toMatchSnapshot('events');12});13import { test, expect } from '@playwright/test';14import { trapEventForPluginEventSystem } from '@playwright/test/lib/server/trace/recorder/plugins';15test('should record events', async ({ page }) => {16  await page.click('input[name="q"]');17  await page.type('input[name="q"]', 'hello');18  await page.click('input[name="btnK"]');19  await page.waitForResponse('**/complete/search**');20  const events = trapEventForPluginEventSystem(page);21  await page.click('text=Images');22  await page.waitForResponse('**/search**');23  expect(events).toMatchSnapshot('events');24});25We can also use the expect function to compare the actual result and the expected result. The expect function is used to compare the actual result and the expected result. If the actual result is the same as the expected result, the test case will pass; if the actual result is not the same as the expected result, the test case will fail. In the above code, we use the expect function to compare the actual result and the expected result. If the actual result is the same as the expected

Using AI Code Generation

1const {trapEventForPluginEventSystem} = require('playwright/lib/server/inspector');2const {readFileSync} = require('fs');3const {join} = require('path');4const {parse} = require('playwright');5const {test} = require('playwright/lib/server/test');6test('test', async ({browser}) => {7  const page = await browser.newPage();8  const [event] = await Promise.all([9    new Promise(resolve => {10      trapEventForPluginEventSystem('Page.frameNavigated', (event) => {11        resolve(event);12      });13    }),14  ]);15  console.log(event);16});17{ method: 'Page.frameNavigated',18   { frame:19      { id: 'E1F6F4A4A4D6C4E6F4D0D4F6F4D6C4E6',

Using AI Code Generation

1const playwright = require('playwright-internal');2const { firefox } = playwright;3const browser = await firefox.launch();4const context = await browser.newContext();5const page = await context.newPage();6page.on('console', msg => console.log('PAGE LOG:', msg.text()));7await page.evaluate(() => {8  window.addEventListener('click', event => {9    console.log('click event');10  });11});12await page.trapEventForPluginEventSystem('click');13await page.trapEventForPluginEventSystem('keydown');14await page.trapEventForPluginEventSystem('keydown', { key: 'Enter' });15await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter' });16await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter', keyCode: 13 });17await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter', keyCode: 13, which: 13 });18await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter', keyCode: 13, which: 13, charCode: 13 });19await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter', keyCode: 13, which: 13, charCode: 13, shiftKey: true });20await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter', keyCode: 13, which: 13, charCode: 13, shiftKey: true, ctrlKey: true });21await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter', keyCode: 13, which: 13, charCode: 13, shiftKey: true, ctrlKey: true, altKey: true });22await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter', keyCode: 13, which: 13, charCode: 13, shiftKey: true, ctrlKey: true, altKey: true, metaKey: true });23await page.trapEventForPluginEventSystem('keydown', { key: 'Enter', code: 'Enter', keyCode: 13,

Using AI Code Generation

1const {trapEventForPluginEventSystem} = require('playwright/lib/server/events');2trapEventForPluginEventSystem('page', 'request', callback);3trapEventForPluginEventSystem('page', 'response', callback);4trapEventForPluginEventSystem('page', 'requestfailed', callback);5trapEventForPluginEventSystem('page', 'requestfinished', callback);6trapEventForPluginEventSystem('page', 'console', callback);7trapEventForPluginEventSystem('page', 'dialog', callback);8trapEventForPluginEventSystem('page', 'download', callback);9trapEventForPluginEventSystem('page', 'error', callback);10trapEventForPluginEventSystem('page', 'frameattached', callback);11trapEventForPluginEventSystem('page', 'framedetached', callback);12trapEventForPluginEventSystem('page', 'framenavigated', callback);13trapEventForPluginEventSystem('page', 'load', callback);14trapEventForPluginEventSystem('page', 'pageerror', callback);15trapEventForPluginEventSystem('page', 'popup', callback);16trapEventForPluginEventSystem('page', 'video', callback);17trapEventForPluginEventSystem('page', 'workercreated', callback);18trapEventForPluginEventSystem('page', 'workerdestroyed', callback);

Using AI Code Generation

1const playwright = require('playwright');2const { trapEventForPluginEventSystem } = require('playwright-core/lib/server/chromium/crBrowser');3const fs = require('fs');4(async () => {5  const browser = await playwright.chromium.launch({ headless: false });6  const context = await browser.newContext();7  const page = await context.newPage();8  trapEventForPluginEventSystem(page, (event) => {9    fs.appendFileSync('events.txt', JSON.stringify(event) + '10');11  });12  await browser.close();13})();

Using AI Code Generation

1const { trapEventForPluginEventSystem } = require("playwright-core/lib/internal/inspector/events");2const { Page } = require("playwright-core/lib/server/page");3Page.prototype.trapEventForPluginEventSystem = function (event) {4    console.log("trapEventForPluginEventSystem called");5    trapEventForPluginEventSystem.call(this, event);6};7const { chromium } = require("playwright-core");8const { Page } = require("playwright-core/lib/server/page");9(async () => {10    const browser = await chromium.launch({11    });12    const context = await browser.newContext();13    const page = await context.newPage();14    Page.prototype.trapEventForPluginEventSystem = function (event) {15        console.log("trapEventForPluginEventSystem called");16        trapEventForPluginEventSystem.call(this, event);17    };18})();19const { chromium } = require("playwright-core");20const { Page } = require("playwright-core/lib/server/page");21(async () => {22    const browser = await chromium.launch({23    });24    const context = await browser.newContext();25    const page = await context.newPage();26    Page.prototype.trapEventForPluginEventSystem = function (event) {27        console.log("trapEventForPluginEventSystem called");28        trapEventForPluginEventSystem.call(this, event);29    };30})();31const { chromium } = require("playwright-core");32const { Page } = require("playwright-core/lib/server/page");33(async () => {34    const browser = await chromium.launch({35    });36    const context = await browser.newContext();37    const page = await context.newPage();

Using AI Code Generation

1const { trapEventForPluginEventSystem } = require('playwright/lib/server/inspector/inspector');2const { EventEmitter } = require('events');3class TestEventEmitter extends EventEmitter {4  constructor() {5    super();6  }7}8const test = new TestEventEmitter();9trapEventForPluginEventSystem(test, 'testevent', (evt) => {10  console.log('testevent emitted', evt);11});12test.emit('testevent', {foo: 'bar'});13window.addEventListener('testevent', (evt) => {14  console.log('testevent received', evt);15});16window.testEvent = new Event('testevent');17window.dispatchEvent(window.testEvent);18const { test, expect } = require('@playwright/test');19test('test event', async ({ page }) => {20  await page.goto('test.html');21  await page.addScriptTag({ path: 'test.js' });22  await page.waitForEvent('testevent');23  const emittedEvent = await page.evaluate(() => window.testEvent);24  expect(emittedEvent).toEqual({foo: 'bar'});25});26-   [PlaywrightPluginEventSystem](#playwrightplugineventsystem)27    -   [Parameters](#parameters)28    -   [Examples](#examples)29-   [trapEventForPluginEventSystem](#trapeventforplugineventsystem)30    -   [Parameters](#parameters-1)31    -   [Examples](#examples-1)32-   [untrapEventForPluginEventSystem](#untrapeventforplugineventsystem)33    -   [Parameters](#parameters-2)34    -   [Examples](#examples-2)35-   [getTrappedEventsForPluginEventSystem](#gettrappedeventsforplugineventsystem)36    -   [Parameters](#parameters-3)37    -   [Examples](#examples-3)

StackOverFlow community discussions

Questions

Discussion

Jest + Playwright - Test callbacks of event-based DOM library

firefox browser does not start in playwright

Running Playwright in Azure Function

How to run a list of test suites in a single file concurrently in jest?

firefox browser does not start in playwright

Is it possible to get the selector from a locator object in playwright?

This question is quite close to a "need more focus" question. But let's try to give it some focus:

Does Playwright has access to the cPicker object on the page? Does it has access to the window object?

Yes, you can access both cPicker and the window object inside an evaluate call.

Should I trigger the events from the HTML file itself, and in the callbacks, print in the DOM the result, in some dummy-element, and then infer from that dummy element text that the callbacks fired?

Exactly, or you can assign values to a javascript variable:

const cPicker = new ColorPicker({
  onClickOutside(e){
  },
  onInput(color){
    window['color'] = color;
  },
  onChange(color){
    window['result'] = color;
  }
})

And then

it('Should call all callbacks with correct arguments', async() => {
    await page.goto(`http://localhost:5000/tests/visual/basic.html`, {waitUntil:'load'})

    // Wait until the next frame
    await page.evaluate(() => new Promise(requestAnimationFrame))

    // Act
   
    // Assert
    const result = await page.evaluate(() => window['color']);
    // Check the value
})

https://stackoverflow.com/questions/65477895/jest-playwright-test-callbacks-of-event-based-dom-library

I found the error. It was because of some missing libraries need. I discovered this when I downgraded playwright to version 1.9 and ran the the code then this was the error msg:

(node:12876) UnhandledPromiseRejectionWarning: browserType.launch: Host system is missing dependencies!

Some of the Universal C Runtime files cannot be found on the system. You can fix
that by installing Microsoft Visual C++ Redistributable for Visual Studio from:
https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads

Full list of missing libraries:
    vcruntime140.dll
    msvcp140.dll
Error
    at Object.captureStackTrace (D:\Projects\snkrs-play\node_modules\playwright\lib\utils\stackTrace.js:48:19)
    at Connection.sendMessageToServer (D:\Projects\snkrs-play\node_modules\playwright\lib\client\connection.js:69:48)
    at Proxy.<anonymous> (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:64:61)
    at D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:64:67
    at BrowserType._wrapApiCall (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:77:34)
    at BrowserType.launch (D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:55:21)
    at D:\Projects\snkrs-play\index.js:4:35
    at Object.<anonymous> (D:\Projects\snkrs-play\index.js:7:3)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:12876) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:12876) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

A list of missing libraries was provided. After successful installments, firefox ran fine. I upgraded again to version 1.10 and firefox still works.

https://stackoverflow.com/questions/66984974/firefox-browser-does-not-start-in-playwright

Assuming you are not running test with the --runinband flag, the simple answer is yes but it depends ????

There is a pretty comprehensive GitHub issue jest#6957 that explains certain cases of when tests are run concurrently or in parallel. But it seems to depend on a lot of edge cases where jest tries its best to determine the fastest way to run the tests given the circumstances.

To my knowledge there is no way to force jest to run in parallel.

Aside

Have you considered using playwright instead of puppeteer with jest? Playwright has their own internally built testing library called @playwright/test that is used in place of jest with a similar API. This library allows for explicitly defining test groups in a single file to run in parallel (i.e. test.describe.parallel) or serially (i.e. test.describe.serial). Or even to run all tests in parallel via a config option.

// parallel
test.describe.parallel('group', () => {
  test('runs in parallel 1', async ({ page }) => {});
  test('runs in parallel 2', async ({ page }) => {});
});

// serial
test.describe.serial('group', () => {
  test('runs first', async ({ page }) => {});
  test('runs second', async ({ page }) => {});
});

https://stackoverflow.com/questions/73497773/how-to-run-a-list-of-test-suites-in-a-single-file-concurrently-in-jest

I found the error. It was because of some missing libraries need. I discovered this when I downgraded playwright to version 1.9 and ran the the code then this was the error msg:

(node:12876) UnhandledPromiseRejectionWarning: browserType.launch: Host system is missing dependencies!

Some of the Universal C Runtime files cannot be found on the system. You can fix
that by installing Microsoft Visual C++ Redistributable for Visual Studio from:
https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads

Full list of missing libraries:
    vcruntime140.dll
    msvcp140.dll
Error
    at Object.captureStackTrace (D:\Projects\snkrs-play\node_modules\playwright\lib\utils\stackTrace.js:48:19)
    at Connection.sendMessageToServer (D:\Projects\snkrs-play\node_modules\playwright\lib\client\connection.js:69:48)
    at Proxy.<anonymous> (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:64:61)
    at D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:64:67
    at BrowserType._wrapApiCall (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:77:34)
    at BrowserType.launch (D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:55:21)
    at D:\Projects\snkrs-play\index.js:4:35
    at Object.<anonymous> (D:\Projects\snkrs-play\index.js:7:3)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:12876) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:12876) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

A list of missing libraries was provided. After successful installments, firefox ran fine. I upgraded again to version 1.10 and firefox still works.

https://stackoverflow.com/questions/66984974/firefox-browser-does-not-start-in-playwright

Well this is one way, but not sure if it will work for all possible locators!.

// Get a selector from a playwright locator
import { Locator } from "@playwright/test";
export function extractSelector(locator: Locator) {
    const selector = locator.toString();
    const parts = selector.split("@");
    if (parts.length !== 2) { throw Error("extractSelector: susupect that this is not a locator"); }
    if (parts[0] !== "Locator") { throw Error("extractSelector: did not find locator"); }
    return parts[1];
}

https://stackoverflow.com/questions/72044959/is-it-possible-to-get-the-selector-from-a-locator-object-in-playwright

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