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How to use getListenerSetKey method in Playwright Internal

Best JavaScript code snippet using playwright-internal

index.js

Source:index.js

...40export const IS_CAPTURE_PHASE = 1 << 2;41export function listenToNonDelegatedEvent(domEventName, target){42  const isCapturePhaseListener = false;43  const listenerSet = getEventListenerSet(target);44  const listenerSetKey = getListenerSetKey(45    domEventName, 46    isCapturePhaseListener47  );48  if(!listenerSet.has(listenerSetKey)){49    addTrappedEventListener(50      domEventName,51      target,52      isCapturePhaseListener,53      IS_NON_DELEGATED54    );55    listenerSet.add(listenerSetKey);56  }57}58function getListenerSetKey(domEventName,capture){59  return `${domEventName}__${capture ? 'capture' : 'bubble'}`;60}61function listenToNativeEvent(domEventName, target, isCapturePhaseListener){62  let eventSystemFlags = 0;63  if (isCapturePhaseListener){64    eventSystemFlags |= IS_CAPTURE_PHASE;65  }66  addTrappedEventListener(67    domEventName,68    target,69    isCapturePhaseListener,70    eventSystemFlags71  )72}...

DOMPluginEvnentSystem.js

Source: DOMPluginEvnentSystem.js

...30  eventSystemFlags = 0 // äºä»¶ç³»ç»æ è¯31) {32  // åä¸ä¸ªå®¹å¨ä¸çåä¸ä¸ªé¶æ®µçåä¸ä¸ªäºä»¶åªç»å®ä¸æ¬¡33  let listenerSet = getEventListenerSet(rootContainerElement)34  let listenerSetKey = getListenerSetKey(domEventName, isCapturePhaseListener)35  if (!listenerSet.has(listenerSetKey)) {   36    // å¦ææ²¡æç»å®è¿ï¼å°±æ·»å ä¸è¿ä¸ªkey37    if (isCapturePhaseListener) {38      eventSystemFlags |= IS_CAPTURE_PHASE // let a = 1; a+=239    }40    addTrappedEventListener(41      rootContainerElement,42      domEventName,43      eventSystemFlags,44      isCapturePhaseListener45    )46    listenerSet.add(listenerSetKey)47  }48}49function addTrappedEventListener(50  rootContainerElement,51  domEventName,52  eventSystemFlags,53  isCapturePhaseListener54) {55  let listener = dispatchEvent.bind(56    null,57    domEventName,58    eventSystemFlags,59    rootContainerElement60  )61  if (isCapturePhaseListener) {62    addEventCaptureListener(rootContainerElement, domEventName, listener)63  } else {64    addEventBubbleListener(rootContainerElement, domEventName, listener)65  }66}67function getListenerSetKey(domEventName, isCapturePhaseListener) {68  // click_capture   click_bubble69  return `${domEventName}__${isCapturePhaseListener ? "capture" : "bubble"}`70}71export function dispatchEventForPluginEventSystem(72  domEventName,73  eventSystemFlags,74  nativeEvent,75  targetInst,76  targetContainer77) {78  let nativeEventTarget = nativeEvent.target79  const dispatchQueue = []80  // ç±æä»¶æ¥æåäºä»¶å¤çå½æ°81  // ç±æä»¶æ¥å¡«åè¿ä¸ªdispatchQueueæ°ç»...

DOMPluginEventSystem.js

Source:DOMPluginEventSystem.js

...118    eventSystemFlags |= IS_NON_DELEGATED;119    target = targetElement;120  }121  const listenerSet = getEventListenerSet(target);122  const listenerSetKey = getListenerSetKey(123    domEventName,124    isCapturePhaseListener125  );126  if (!listenerSet.has(listenerSetKey)) {127    if (isCapturePhaseListener) {128      eventSystemFlags |= IS_CAPTURE_PHASE;129    }130    addTrappedEventListener(131      target,132      domEventName,133      eventSystemFlags,134      isCapturePhaseListener135    );136    listenerSet.add(listenerSetKey);137  }138};139const listenToAllSupportedEvents = (rootContainerElement) => {140  if (rootContainerElement[listeningMarker]) return;141  rootContainerElement[listeningMarker] = true;142  allNativeEvents.forEach((domEventName) => {143    if (!nonDelegatedEvents.has(domEventName)) {144      listenToNativeEvent(domEventName, false, rootContainerElement, null);145    }146    listenToNativeEvent(domEventName, true, rootContainerElement, null);147  });148};149const listenToNonDelegatedEvent = (domEventName, targetElement) => {150  const isCapturePhaseListener = false;151  const listenerSet = getEventListenerSet(targetElement);152  const listenerSetKey = getListenerSetKey(153    domEventName,154    isCapturePhaseListener155  );156  if (!listenerSet.has(listenerSetKey)) {157    addTrappedEventListener(158      targetElement,159      domEventName,160      IS_NON_DELEGATED,161      isCapturePhaseListener162    );163    listenerSet.add(listenerSetKey);164  }165};166export {...

Using AI Code Generation

1const { getListenerSetKey } = require('playwright/lib/utils/utils');2const listenerSetKey = getListenerSetKey('click');3console.log(listenerSetKey);4const { getListenerSetKey } = require('playwright/lib/utils/utils');5const listenerSetKey = getListenerSetKey('click');6console.log(listenerSetKey);7const { getListenerSetKey } = require('playwright/lib/utils/utils');8const listenerSetKey = getListenerSetKey('click');9console.log(listenerSetKey);10const { getListenerSetKey } = require('playwright/lib/utils/utils');11const listenerSetKey = getListenerSetKey('click');12console.log(listenerSetKey);13const { getListenerSetKey } = require('playwright/lib/utils/utils');14const listenerSetKey = getListenerSetKey('click');15console.log(listenerSetKey);16const { getListenerSetKey } = require('playwright/lib/utils/utils');17const listenerSetKey = getListenerSetKey('click');18console.log(listenerSetKey);19const { getListenerSetKey } = require('playwright/lib/utils/utils');20const listenerSetKey = getListenerSetKey('click');21console.log(listenerSetKey);22const { getListenerSetKey } = require('playwright/lib/utils/utils');23const listenerSetKey = getListenerSetKey('click');24console.log(listenerSetKey);25const { getListenerSetKey } = require('playwright/lib/utils/utils');26const listenerSetKey = getListenerSetKey('click');27console.log(listenerSetKey);28const { getListenerSetKey } = require('playwright/lib/utils/utils');29const listenerSetKey = getListenerSetKey('click');30console.log(listenerSetKey);31const { getListenerSetKey }

Using AI Code Generation

1const { getListenerSetKey } = require('playwright-core/lib/server/frames');2const frame = page.mainFrame();3const key = getListenerSetKey(frame, 'load');4frame._listenerSets.get(key).size5const page = await browser.newPage();6await page.exposeBinding('getListenerSetKey', (source, frame, eventName) => {7  const { getListenerSetKey } = require('playwright-core/lib/server/frames');8  const key = getListenerSetKey(frame, eventName);9  return frame._listenerSets.get(key).size;10});11const count = await page.evaluate((eventName) => {12  const frame = window.document.querySelector('iframe').contentWindow;13  return window.getListenerSetKey(frame, eventName);14}, 'load');15console.log(count);

Using AI Code Generation

1const { getListenerSetKey } = require('@playwright/test/lib/workerRunner');2const key = getListenerSetKey('event');3console.log(key);4const { getListenerSetKey } = require('@playwright/test/lib/workerRunner');5const key = getListenerSetKey('event', 'value');6console.log(key);7const { getListenerSetKey } = require('@playwright/test/lib/workerRunner');8const key = getListenerSetKey('event', 'value', 'value1');9console.log(key);10const { getListenerSetKey } = require('@playwright/test/lib/workerRunner');11const key = getListenerSetKey('event', 'value', 'value1', 'value2');12console.log(key);13const { getListenerSetKey } = require('@playwright/test/lib/workerRunner');14const key = getListenerSetKey('event', 'value', 'value1', 'value2', 'value3');15console.log(key);16const { getListenerSetKey } = require('@playwright/test/lib/workerRunner');17const key = getListenerSetKey('event', 'value', 'value1', 'value2', 'value3', 'value4');18console.log(key);19const { getListenerSetKey } = require('@playwright/test/lib/workerRunner');20const key = getListenerSetKey('event', 'value', 'value1', 'value2', 'value3', 'value4', 'value5');21console.log(key);

Using AI Code Generation

1const { getListenerSetKey } = require('@playwright/test/lib/utils/utils');2const key = getListenerSetKey('test', 'testEvent');3console.log(key);4const { getListenerSetKey } = require('@playwright/test/lib/utils/utils');5const key = getListenerSetKey('test', 'testEvent');6console.log(key);7  _addEventHandler(event: string, handler: Function) {8    const key = getListenerSetKey(this, event);9    if (!this._listenerSet[key])10      this._listenerSet[key] = new Set();11    this._listenerSet[key].add(handler);12  }13  _removeEventHandler(event: string, handler: Function) {14    const key = getListenerSetKey(this, event);15    if (!this._listenerSet[key])16      return;17    this._listenerSet[key].delete(handler);18    if (!this._listenerSet[key].size)19      delete this._listenerSet[key];20  }21  _emitEvent(event: string, ...args: any[]) {22    const key = getListenerSetKey(this, event);23    if (!this._listenerSet[key])24      return;25    for (const handler of this._listenerSet[key])26      handler(...args);27  }28  _removeAllEventListeners() {29    this._listenerSet = {};30  }31  _addEventHandler(event: string, handler: Function) {32    const key = getListenerSetKey(this, event);33    if (!this._listenerSet[key])34      this._listenerSet[key] = new Set();

Using AI Code Generation

1const { getListenerSetKey } = require('playwright/lib/utils/utils');2const result = getListenerSetKey('event', 'selector', 'frame');3console.log(result);4const { getListenerSetKey } = require('playwright/lib/utils/utils');5const result = getListenerSetKey('event', 'selector', 'frame');6console.log(result);7const { getListenerSetKey } = require('playwright/lib/utils/utils');8const result = getListenerSetKey('event', 'selector', 'frame');9console.log(result);10const { getListenerSetKey } = require('playwright/lib/utils/utils');11const result = getListenerSetKey('event', 'selector', 'frame');12console.log(result);13const { getListenerSetKey } = require('playwright/lib/utils/utils');14const result = getListenerSetKey('event', 'selector', 'frame');15console.log(result);16const { getListenerSetKey } = require('playwright/lib/utils/utils');17const result = getListenerSetKey('event', 'selector', 'frame');18console.log(result);19const { getListenerSetKey } = require('playwright/lib/utils/utils');20const result = getListenerSetKey('event', 'selector', 'frame');21console.log(result);22const { getListenerSetKey } = require('playwright/lib/utils/utils');23const result = getListenerSetKey('event', 'selector', 'frame');24console.log(result

Using AI Code Generation

1const { getListenerSetKey } = require('@playwright/test/lib/server/transport');2console.log(getListenerSetKey('Test', 'test'));3const { getListenerSetKey } = require('@playwright/test/lib/server/transport');4console.log(getListenerSetKey('Test', 'test'));5const { getListenerSetKey } = require('playwright/lib/server/transport');6console.log(getListenerSetKey('Test', 'test'));

StackOverFlow community discussions

Questions

Discussion

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

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

Running Playwright in Azure Function

firefox browser does not start in playwright

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

firefox browser does not start 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

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

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

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