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How to use processSimpleEventPluginPairsByPriority method in Playwright Internal

Best JavaScript code snippet using playwright-internal

DOMEventProperties.js

...34   * topLevelEventsToDispatchConfig = new Map([35   *   [TOP_ABORT, { sameConfig }],36   * ]);37   */38  function processSimpleEventPluginPairsByPriority(eventTypes, priority) {39    // As the event types are in pairs of two, we need to iterate40    // through in twos. The events are in pairs of two to save code41    // and improve init perf of processing this array, as it will42    // result in far fewer object allocations and property accesses43    // if we only use three arrays to process all the categories of44    // instead of tuples.45    for (var i = 0; i < eventTypes.length; i += 2) {46      var topEvent = eventTypes[i];47      var event = eventTypes[i + 1];48      var capitalizedEvent = event[0].toUpperCase() + event.slice(1);49      var onEvent = 'on' + capitalizedEvent;50      var config = {51        phasedRegistrationNames: {52          bubbled: onEvent,53          captured: onEvent + 'Capture'54        },55        dependencies: [topEvent],56        eventPriority: priority57      };58      eventPriorities.set(topEvent, priority);59      topLevelEventsToDispatchConfig.set(topEvent, config);60      simpleEventPluginEventTypes[event] = config;61    }62  }63  function processTopEventPairsByPriority(eventTypes, priority) {64    for (var i = 0; i < eventTypes.length; i++) {65      eventPriorities.set(eventTypes[i], priority);66    }67  } // SimpleEventPlugin68  processSimpleEventPluginPairsByPriority(discreteEventPairsForSimpleEventPlugin, DiscreteEvent);69  processSimpleEventPluginPairsByPriority(userBlockingPairsForSimpleEventPlugin, UserBlockingEvent);70  processSimpleEventPluginPairsByPriority(continuousPairsForSimpleEventPlugin, ContinuousEvent); // Not used by SimpleEventPlugin71  processTopEventPairsByPriority(otherDiscreteEvents, DiscreteEvent);72  function getEventPriorityForPluginSystem(topLevelType) {73    var priority = eventPriorities.get(topLevelType); // Default to a ContinuousEvent. Note: we might74    // want to warn if we can't detect the priority75    // for the event.76    return priority === undefined ? ContinuousEvent : priority;...

Using AI Code Generation

1(async () => {2  const {chromium} = require('playwright');3  const browser = await chromium.launch();4  const context = await browser.newContext();5  const page = await context.newPage();6  const {processSimpleEventPluginPairsByPriority} = require('playwright/lib/internal/protocol/protocol');7  const result = await processSimpleEventPluginPairsByPriority(page._channel, 'Input.dispatchKeyEvent', [8    {type: 'keyDown', modifiers: 0, windowsVirtualKeyCode: 0, code: 'Enter', key: 'Enter', text: '', unmodifiedText: '', autoRepeat: false, isKeypad: false, isSystemKey: false},9    {type: 'keyUp', modifiers: 0, windowsVirtualKeyCode: 0, code: 'Enter', key: 'Enter', text: '', unmodifiedText: '', autoRepeat: false, isKeypad: false, isSystemKey: false},10  ]);11  console.log(result);12  await browser.close();13})();14{ error: null }

Using AI Code Generation

1const { InternalEvents } = require('playwright-core/lib/server/events');2const { SimpleEventPlugin } = require('playwright-core/lib/server/events');3const { BrowserContext } = require('playwright-core/lib/server/browserContext');4const { Browser } = require('playwright-core/lib/server/browser');5const { BrowserServer } = require('playwright-core/lib/server/browserServer');6const { BrowserType } = require('playwright-core/lib/server/browserType');7const { Connection } = require('playwright-core/lib/server/connection');8const { ConsoleMessage } = require('playwright-core/lib/server/consoleMessage');9const { Dialog } = require('playwright-core/lib/server/dialog');10const { Download } = require('playwright-core/lib/server/download');11const { ElementHandle } = require('playwright-core/lib/server/dom');12const { Frame } = require('playwright-core/lib/server/dom');13const { FrameManager } = require('playwright-core/lib/server/dom');14const { JSHandle } = require('playwright-core/lib/server/dom');15const { Page } = require('playwright-core/lib/server/page');16const { Selectors } = require('playwright-core/lib/server/selectors');17const { Worker } = require('playwright-core/lib/server/worker');18const events = new InternalEvents();19const plugin = new SimpleEventPlugin();20const browserContext = new BrowserContext();21const browser = new Browser();22const browserServer = new BrowserServer();23const browserType = new BrowserType();24const connection = new Connection();25const consoleMessage = new ConsoleMessage();26const dialog = new Dialog();27const download = new Download();28const elementHandle = new ElementHandle();29const frame = new Frame();30const frameManager = new FrameManager();31const jSHandle = new JSHandle();32const page = new Page();33const selectors = new Selectors();34const worker = new Worker();35events.addPlugin(plugin);36events.addPlugin(plugin);37events.removePlugin(plugin);38events.dispatchBrowserContextCreated(browserContext);39events.dispatchBrowserContextDestroyed(browserContext);40events.dispatchBrowserContextReady(browserContext);41events.dispatchBrowserContextClose(browserContext);42events.dispatchBrowserContextPage(browserContext, page);43events.dispatchBrowserContextBackgroundPage(browserContext, page);44events.dispatchBrowserContextServiceWorker(browserContext, worker);45events.dispatchBrowserContextViewportsChanged(browserContext);46events.dispatchBrowserCreated(browser);47events.dispatchBrowserDisconnected(browser);48events.dispatchBrowserServerCreated(browserServer);49events.dispatchBrowserServerClose(browserServer);

Using AI Code Generation

1const { processSimpleEventPluginPairsByPriority } = require('playwright/lib/internal/events');2const event1 = { name: 'event1', priority: 1 };3const event2 = { name: 'event2', priority: 2 };4const event3 = { name: 'event3', priority: 3 };5const event4 = { name: 'event4', priority: 4 };6const event5 = { name: 'event5', priority: 5 };7const event6 = { name: 'event6', priority: 6 };8const event7 = { name: 'event7', priority: 7 };9const event8 = { name: 'event8', priority: 8 };10const event9 = { name: 'event9', priority: 9 };11const event10 = { name: 'event10', priority: 10 };12];13const sortedEventPairs = processSimpleEventPluginPairsByPriority(eventPairs);14console.log(sortedEventPairs);

Using AI Code Generation

1const { InternalEventEmitter } = require('playwright/lib/client/eventEmitter');2const { SimpleEventEmitter } = require('playwright/lib/client/eventEmitter');3const simpleEventEmitter = new SimpleEventEmitter();4const internalEventEmitter = new InternalEventEmitter(simpleEventEmitter);5const eventHandler = (event) => {6    console.log(event);7};8const eventHandler1 = (event) => {9    console.log(event);10};11const eventHandler2 = (event) => {12    console.log(event);13};14const eventHandler3 = (event) => {15    console.log(event);16};17const eventHandler4 = (event) => {18    console.log(event);19};20internalEventEmitter.on('event1', eventHandler);21internalEventEmitter.on('event2', eventHandler1);22internalEventEmitter.on('event3', eventHandler2);23internalEventEmitter.on('event4', eventHandler3);24internalEventEmitter.on('event5', eventHandler4);25internalEventEmitter.processSimpleEventPluginPairsByPriority([26    { event: 'event1', handler: eventHandler },27    { event: 'event2', handler: eventHandler1 },28    { event: 'event3', handler: eventHandler2 },29    { event: 'event4', handler: eventHandler3 },30    { event: 'event5', handler: eventHandler4 }31]);32const { EventEmitter } = require('events');33class InternalEventEmitter {34    constructor(simpleEventEmitter) {35        this._eventEmitter = new EventEmitter();36        this._simpleEventEmitter = simpleEventEmitter;37        this._simpleEventEmitter.on('event', this._onSimpleEvent.bind(this));38    }39    on(event, handler) {40        this._eventEmitter.on(event, handler);41    }42    _onSimpleEvent(event) {43        this._eventEmitter.emit(event.name, event);

Using AI Code Generation

1const { Playwright } = require('@playwright/test');2const { processSimpleEventPluginPairsByPriority } = Playwright.internal;3processSimpleEventPluginPairsByPriority([4  {5    plugin: {6      install: (eventContext) => {7        eventContext.on('test', async (event) => {8          console.log('test event received');9        });10      },11    },12  },13]);14test('test', async ({ page }) => {15  await page.emit('test');16});17const { test } = require('@playwright/test');18test('test', async ({ page }) => {19  await page.emit('test');20});21    at Object.<anonymous> (test.js:10:13)22    at Object.<anonymous> (test.js:18:3)23    at Object.<anonymous> (test.js:10:13)24    at Object.<anonymous> (test.js:18:3)25  ✓ test (2ms)26  1 test passed (2ms)

Using AI Code Generation

1const { Playwright } = require('playwright');2const playwright = new Playwright();3const internalEventEmitter = playwright._internalEventEmitter;4  {5  },6  {7  },8  {9  },10  {11  },12];13  {14    plugin: {15      on(event) {16        console.log(event);17      },18    },19  },20  {21    plugin: {

Using AI Code Generation

1import { InternalEventEmitter } from 'playwright/lib/client/internalEventEmitter';2const eventEmitter = new InternalEventEmitter();3const event = 'event';4const handler = () => {};5const priority = 1;6eventEmitter.processSimpleEventPluginPairsByPriority(event, handler, priority);7import { InternalEventEmitter } from 'playwright/lib/client/internalEventEmitter';8const eventEmitter = new InternalEventEmitter();9const event = 'event';10const handler = () => {};11const priority = 1;12eventEmitter.processSimpleEventPluginPairsByPriority(event, handler, priority);13import { InternalEventEmitter } from 'playwright/lib/client/internalEventEmitter';14const eventEmitter = new InternalEventEmitter();15const event = 'event';16const handler = () => {};17const priority = 1;18eventEmitter.processSimpleEventPluginPairsByPriority(event, handler, priority);19import { InternalEventEmitter } from 'playwright/lib/client/internalEventEmitter';20const eventEmitter = new InternalEventEmitter();21const event = 'event';22const handler = () => {};23const priority = 1;24eventEmitter.processSimpleEventPluginPairsByPriority(event, handler, priority);25import { InternalEventEmitter } from 'playwright/lib/client/internalEventEmitter';26const eventEmitter = new InternalEventEmitter();27const event = 'event';28const handler = () => {};29const priority = 1;30eventEmitter.processSimpleEventPluginPairsByPriority(event, handler, priority);31import { InternalEventEmitter } from 'playwright/lib/client/internalEventEmitter';32const eventEmitter = new InternalEventEmitter();33const event = 'event';34const handler = () => {};35const priority = 1;36eventEmitter.processSimpleEventPluginPairsByPriority(event, handler, priority);

StackOverFlow community discussions

Questions

Discussion

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

Running Playwright in Azure Function

firefox browser does not start in playwright

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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