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How to use finalizeInitialChildren method in Playwright Internal

Best JavaScript code snippet using playwright-internal

ReactPixiFiber.js

...77    false,78    "ReactPixiFiber does not support text instances. Use `Text` component instead."79  );80}81export function finalizeInitialChildren(82  instance,83  type,84  props,85  rootContainer,86  hostContext87) {88  setInitialProperties(type, instance, props, rootContainer, hostContext);89  return true;90}91export function getChildHostContext(parentHostContext, type, rootContainer) {92  return parentHostContext;93}94export function getRootHostContext(rootContainer) {95  return emptyObject;...

renderer.js

Source: renderer.js

1import Reconciler from 'react-reconciler'2import { createElement, updateElement } from './helpers.js'3const logRenderCalls = false4const getRootHostContext = (rootContainerInstance) => {5    if (logRenderCalls) log('getRootHostContext')6    return {}7}8const getChildHostContext = (9    parentHostContext,10    type,11    rootContainerInstance12) => {13    if (logRenderCalls) log('getChildHostContext')14    return parentHostContext15}16const getPublicInstance = (instance) => {17    if (logRenderCalls) log('getPublicInstance')18    return instance19}20const prepareForCommit = (containerInfo) => {21    // Noop22}23const resetAfterCommit = (containerInfo) => {24    // Noop25}26const createInstance = (27    type,28    props,29    rootContainerInstance,30    hostContext,31    internalInstanceHandle32) => {33    if (logRenderCalls) log('createInstance ' + type)34    return createElement(type, props)35}36const appendInitialChild = (parentInstance, child) => {37    if (logRenderCalls) log('appendInitialChild')38    if (parentInstance.name === 'Paragraph') {39        parentInstance.root.appendChild(child)40    } else {41        parentInstance.appendChild(child)42    }43}44const finalizeInitialChildren = (45    parentInstance,46    type,47    props,48    rootContainerInstance,49    hostContext50) => {51    if (logRenderCalls) log('finalizeInitialChildren')52    return false53}54const prepareUpdate = (55    instance,56    type,57    oldProps,58    newProps,59    rootContainerInstance,60    hostContext61) => {62    // Computes the diff for an instance. Fiber can reuse this work even if it63    // pauses or abort rendering a part of the tree.64    // log('prepareUpdate')65    return true66}67const shouldSetTextContent = (type, props) => {68    if (logRenderCalls) // log('shouldSetTextContent')69    return false70}71const shouldDeprioritizeSubtree = (type, props) => {72    if (logRenderCalls) log('shouldDeprioritizeSubtree')73    return false74}75const createTextInstance = (76    text,77    rootContainerInstance,78    hostContext,79    internalInstanceHandle80) => {81    if (logRenderCalls) log('createTextInstance: ' + text)82}83const scheduleTimeout = setTimeout84const cancelTimeout = clearTimeout85const noTimeout = 086const now = Date.now87const isPrimaryRenderer = true88const warnsIfNotActing = true89const supportsMutation = true90const appendChild = (parentInstance, child) => {91    if (logRenderCalls) log('appendChild')92    if (parentInstance.name == 'Paragraph') {93        parentInstance.root.appendChild(child)94    } else {95        parentInstance.appendChild(child)96    }97}98const appendChildToContainer = (parentInstance, child) => {99    if (logRenderCalls) log('appendChildToContainer')100    parentInstance.root = child101}102const commitTextUpdate = (textInstance, oldText, newText) => {103    if (logRenderCalls) log('commitTextUpdate')104    textInstance.text = newText105}106const commitMount = (instance, type, newProps, internalInstanceHandle) => {107    // Noop108}109const commitUpdate = (110    instance,111    updatePayload,112    type,113    oldProps,114    newProps,115    internalInstanceHandle116) => {117    if (logRenderCalls) log('commitUpdate')118    updateElement(instance, type, oldProps, newProps)119}120const insertBefore = (parentInstance, child, beforeChild) => {121    // TODO Move existing child or add new child?122    if (logRenderCalls) log('insertBeforeChild')123    log(parentInstance.name)124    parentInstance.insertBeforeChild(child, beforeChild)125}126const insertInContainerBefore = (parentInstance, child, beforeChild) => {127    if (logRenderCalls) log('Container does not support insertBefore operation')128}129const removeChild = (parentInstance, child) => {130    if (logRenderCalls) log('removeChild')131    parentInstance.removeChild(child)132}133const removeChildFromContainer = (parentInstance, child) => {134    if (logRenderCalls) log('removeChildFromContainer')135    // TODO undefined / placeholder136    parentInstance.root = new PlaceholderElement()137}138const resetTextContent = (instance) => {139    // Noop140}141const hostConfig = {142    getPublicInstance,143    getRootHostContext,144    getChildHostContext,145    prepareForCommit,146    resetAfterCommit,147    createInstance,148    appendInitialChild,149    finalizeInitialChildren,150    prepareUpdate,151    shouldSetTextContent,152    shouldDeprioritizeSubtree,153    createTextInstance,154    scheduleTimeout,155    cancelTimeout,156    noTimeout,157    now,158    isPrimaryRenderer,159    warnsIfNotActing,160    supportsMutation,161    appendChild,162    appendChildToContainer,163    commitTextUpdate,164    commitMount,165    commitUpdate,166    insertBefore,167    insertInContainerBefore,168    removeChild,169    removeChildFromContainer,170    resetTextContent,171}...

HostConfig.js

Source: HostConfig.js

...102    ) {103        104        return createTextElement(text);105    },106    finalizeInitialChildren(node, type, props) {107        108        if( checkIfNodeHasMethods(type)){//if (type === 'graphics') {109            applyMethodsToInstance(node, type, props)110        }111        else{112            finalizeInitialChildren(node, type, props)113        }114        // BUGY SHIT !!!!115        if(props.onLoaded){116            const renderer =getRender(node.stage)117            props.onLoaded(node,renderer)118        }119        120        return false;121    },122    getPublicInstance(inst) {123        return inst;124    },125    prepareForCommit() {126        // noop...

ReactFiberHostContext-test.internal.js

Source: ReactFiberHostContext-test.internal.js

1/**2 * Copyright (c) Facebook, Inc. and its affiliates.3 *4 * This source code is licensed under the MIT license found in the5 * LICENSE file in the root directory of this source tree.6 *7 * @emails react-core8 * @jest-environment node9 */10'use strict';11let React;12let ReactFiberReconciler;13let ConcurrentRoot;14describe('ReactFiberHostContext', () => {15  beforeEach(() => {16    jest.resetModules();17    React = require('react');18    ReactFiberReconciler = require('react-reconciler');19    ConcurrentRoot = require('react-reconciler/src/ReactRootTags');20  });21  it('works with null host context', () => {22    let creates = 0;23    const Renderer = ReactFiberReconciler({24      prepareForCommit: function() {25        return null;26      },27      resetAfterCommit: function() {},28      getRootHostContext: function() {29        return null;30      },31      getChildHostContext: function() {32        return null;33      },34      shouldSetTextContent: function() {35        return false;36      },37      createInstance: function() {38        creates++;39      },40      finalizeInitialChildren: function() {41        return null;42      },43      appendInitialChild: function() {44        return null;45      },46      now: function() {47        return 0;48      },49      appendChildToContainer: function() {50        return null;51      },52      clearContainer: function() {},53      supportsMutation: true,54    });55    const container = Renderer.createContainer(56      /* root: */ null,57      ConcurrentRoot,58      false,59      null,60    );61    Renderer.updateContainer(62      <a>63        <b />64      </a>,65      container,66      /* parentComponent: */ null,67      /* callback: */ null,68    );69    expect(creates).toBe(2);70  });71  it('should send the context to prepareForCommit and resetAfterCommit', () => {72    const rootContext = {};73    const Renderer = ReactFiberReconciler({74      prepareForCommit: function(hostContext) {75        expect(hostContext).toBe(rootContext);76        return null;77      },78      resetAfterCommit: function(hostContext) {79        expect(hostContext).toBe(rootContext);80      },81      getRootHostContext: function() {82        return null;83      },84      getChildHostContext: function() {85        return null;86      },87      shouldSetTextContent: function() {88        return false;89      },90      createInstance: function() {91        return null;92      },93      finalizeInitialChildren: function() {94        return null;95      },96      appendInitialChild: function() {97        return null;98      },99      now: function() {100        return 0;101      },102      appendChildToContainer: function() {103        return null;104      },105      clearContainer: function() {},106      supportsMutation: true,107    });108    const container = Renderer.createContainer(109      rootContext,110      ConcurrentRoot,111      false,112      null,113    );114    Renderer.updateContainer(115      <a>116        <b />117      </a>,118      container,119      /* parentComponent: */ null,120      /* callback: */ null,121    );122  });...

SlackRenderer.js

Source: SlackRenderer.js

...15    internalInstanceHandle16  ) {17    return text;18  },19  finalizeInitialChildren: function finalizeInitialChildren(element, type, props) {20    return false;21  },22  getPublicInstance: function getPublicInstance(instance) {23    return instance;24  },25  prepareForCommit: noop,26  prepareUpdate: function prepareUpdate(element, type, oldProps, newProps) {27    return true;28  },29  resetAfterCommit: noop,30  resetTextContent: noop,31  getRootHostContext: function getRootHostContext(rootInstance) {32    return getHostContextNode(rootInstance);33  },...

ReactFiberCompleteWork.js

Source: ReactFiberCompleteWork.js

...10            const instance = createInstance(type, newProps);11            //è®©æ¤Fiberççå®DOMå±æ§æåinstance12            workInProgress.stateNode = instance;13            //ç»çå®DOMæ·»å å±æ§ åæ¬å¦æç¬çåæ¯åç¬¦ä¸²ææ°åçæåµ14            finalizeInitialChildren(instance, type, newProps);15            break;16        default:17            break;18    }...

ReactDOMHostConfig.dev.js

Source: ReactDOMHostConfig.dev.js

...12}13function createInstance(type) {14  return (0, _ReactDOMComponent.createElement)(type);15}16function finalizeInitialChildren(domElement, type, props) {17  (0, _ReactDOMComponent.setInitialProperties)(domElement, type, props);...

ReactDOMHostConfig.js

Source: ReactDOMHostConfig.js

...5}6export function createInstance(type) {7    return createElement(type);8}9export function finalizeInitialChildren(domElement, type, props) {10    setInitialProperties(domElement, type, props);...

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch({ headless: false });4  const context = await browser.newContext();5  const page = await context.newPage();6  await context.close();7  await browser.close();8})();9const { chromium } = require('playwright');10(async () => {11  const browser = await chromium.launch({ headless: false });12  const context = await browser.newContext();13  const page = await context.newPage();14  await context.close();15  await browser.close();16})();17const { chromium } = require('playwright');18(async () => {19  const browser = await chromium.launch({ headless: false });20  const context = await browser.newContext();21  const page = await context.newPage();22  await context.close();23  await browser.close();24})();25const { chromium } = require('playwright');26(async () => {27  const browser = await chromium.launch({ headless: false });28  const context = await browser.newContext();29  const page = await context.newPage();30  await context.close();31  await browser.close();32})();33const { chromium } = require('playwright');34(async () => {35  const browser = await chromium.launch({ headless: false });36  const context = await browser.newContext();37  const page = await context.newPage();38  await context.close();39  await browser.close();40})();

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const page = await browser.newPage();5  await page.screenshot({ path: 'example.png' });6  await browser.close();7})();8const { chromium } = require('playwright');9async function test() {10  const browser = await chromium.launch();11  const page = await browser.newPage();12  await page.screenshot({ path: 'example.png' });13  await browser.close();14}15test();16const { chromium } = require('playwright');17async function test() {18  const browser = await chromium.launch();19  const page = await browser.newPage();20  await page.screenshot({ path: 'example.png' });21  await browser.close();22}23test();24const { chromium } = require('playwright');25async function test() {26  const browser = await chromium.launch();27  const page = await browser.newPage();28  await page.screenshot({ path: 'example.png' });29  await browser.close();30}31test();32const { chromium } = require('playwright');33async function test() {34  const browser = await chromium.launch();35  const page = await browser.newPage();36  await page.screenshot({ path: 'example.png' });37  await browser.close();38}39test();40const { chromium } = require('playwright');41async function test() {42  const browser = await chromium.launch();43  const page = await browser.newPage();44  await page.screenshot({ path: 'example.png' });45  await browser.close();46}47test();48const { chromium } = require('playwright');49async function test() {50  const browser = await chromium.launch();51  const page = await browser.newPage();

Using AI Code Generation

1const playwright = require('playwright');2(async () => {3  const browser = await playwright.chromium.launch({ headless: false });4  const page = await browser.newPage();5  await page.$eval('input[name="q"]', (input) => {6    input.value = 'Playwright';7  });8  await page.evaluate(() => {9    document.querySelector('input[name="q"]').dispatchEvent(new Event('change'));10  });11  await page.keyboard.press('Enter');12  await page.waitForNavigation();13  await browser.close();14})();15module.exports = {16  use: {17  },18};19import { PlaywrightTestConfig } from '@playwright/test';20const config: PlaywrightTestConfig = {21  use: {22  },23};24export default config;25const { PlaywrightTestConfig } = require('@playwright/test');26const config = {27  use: {28  },29};30module.exports = config;31import { PlaywrightTestConfig } from '@playwright/test';32const config = {33  use: {34  },35};36export default config;37import { PlaywrightTestConfig } from '@playwright/test';38const config: PlaywrightTestConfig = {39  use: {40  },41};42export default config;43import { PlaywrightTestConfig } from '@playwright/test';44const config: PlaywrightTestConfig = {45  use: {46  },47};48export default config;49import { PlaywrightTestConfig } from '@playwright/test';50const config: PlaywrightTestConfig = {51  use: {52  },53};54export default config;55import { PlaywrightTestConfig } from '@playwright/test';56const config: PlaywrightTestConfig = {57  use: {58  },59};60export default config;61import { PlaywrightTestConfig } from '@playwright/test';62const config: PlaywrightTestConfig = {63  use: {

Using AI Code Generation

1const playwright = require('playwright');2const { FinalizeInitialChildren } = require('playwright/lib/server/dom');3const { Page } = require('playwright/lib/server/page');4const { ElementHandle } = require('playwright/lib/server/dom');5(async () => {6  const browser = await playwright.chromium.launch({ headless: false });7  const context = await browser.newContext();8  const page = await context.newPage();9  const rootElement = await page.$('html');10  const elementHandle = await page.$('input[name="q"]');11  const finalizeInitialChildren = new FinalizeInitialChildren(page, rootElement);12  await finalizeInitialChildren.finalizeInitialChildren(elementHandle);13  await browser.close();14})();15class FinalizeInitialChildren extends ElementHandle {16  constructor(page, rootElement) {17    super(page, rootElement);18  }19  async finalizeInitialChildren(elementHandle) {20    const result = await this._page._delegate.finalizeInitialChildren(21    );22    return result;23  }24}25class Page {26  constructor(delegate, context, pageOrError) {27    this._delegate = delegate;28  }29}30class CRPage {31  async finalizeInitialChildren(contextId, objectId, elementHandleId) {32    const { result, exceptionDetails } = await this._client.send(33      {34      }35    );36    return { result, exceptionDetails };37  }38}39class CRConnection {40  async send(method, params = {}) {41    const { id, error, result } = await this._rawSend(42      await this.nextMessageId()43    );44    return { id, error, result, exceptionDetails };45  }46}

Using AI Code Generation

1const { Page } = require('playwright');2const { finalizeInitialChildren } = require('playwright/lib/server/dom/initialization');3const { ElementHandle } = require('playwright/lib/server/dom/elementHandler');4const { Frame } = require('playwright/lib/server/dom/frameTree');5const { createJSHandle } = require('playwright/lib/server/dom/serializers');6async function main() {7  const page = await browser.newPage();8  const frame = page.mainFrame();9  const elementHandle = await frame.$('text=Playwright');10  const element = new ElementHandle(frame, elementHandle._remoteObject, elementHandle._context);11  await finalizeInitialChildren(element, true);12  const html = await element.innerHTML();13  console.log(html);14}15main();16const { Page } = require('playwright');17const { createJSHandle } = require('playwright/lib/server/dom/serializers');18async function main() {19  const page = await browser.newPage();20  const elementHandle = await page.evaluateHandle(() => document.body);21  const jsHandle = createJSHandle(elementHandle._context, elementHandle._remoteObject);22  const html = await jsHandle.innerHTML();23  console.log(html);24}25main();26const { Page } = require('playwright');27const { createJSHandle } = require('playwright/lib/server/dom/serializers');28async function main() {29  const page = await browser.newPage();30  const elementHandle = await page.evaluateHandle(() => document.body);31  const jsHandle = createJSHandle(elementHandle._context, elementHandle._remoteObject);32  const html = await jsHandle.innerHTML();33  console.log(html);34}35main();36const { Page } = require('playwright');37const { createJSHandle } = require('playwright/lib/server/dom/serializers');38async function main() {39  const page = await browser.newPage();40  const elementHandle = await page.evaluateHandle(() => document.body);41  const jsHandle = createJSHandle(elementHandle._context

Using AI Code Generation

1const { _finalizeInitialChildren } = require('playwright/lib/server/dom.js')2const { _setElementState } = require('playwright/lib/server/dom.js')3const { _setAttributesAsText } = require('playwright/lib/server/dom.js')4const { _setAttribute } = require('playwright/lib/server/dom.js')5const { _setNodeName } = require('playwright/lib/server/dom.js')6const { _removeChild } = require('playwright/lib/server/dom.js')7const { _insertChild } = require('playwright/lib/server/dom.js')8const { _setDocumentURL } = require('playwright/lib/server/dom.js')9const { _setBaseURL } = require('playwright/lib/server/dom.js')10const { _setDocumentContent } = require('playwright/lib/server/dom.js')11const { _setChildNodes } = require('playwright/lib/server/dom.js')12const { DOM } = require('playwright/lib/server/dom.js')13const { ElementHandle } = require('playwright/lib/server/dom.js')14const { Frame } = require('playwright/lib/server/dom.js')15const { Page } = require('playwright/lib/server/dom.js')16const { Worker } = require('playwright/lib/server/dom.js')17const { CDPSession } = require('playwright/lib/server/dom.js')18const { helper } = require('playwright/lib/server/dom.js')19const { assert } = require('playwright/lib/server/dom.js')20const { debugError } = require('playwright/lib/server/dom.js')21const { createGuid } = require('playwright/lib/server/dom.js')22const { createJSHandle } = require('playwright/lib/server/dom.js')23const { createHandle } = require('playwright/lib/server/dom.js')24const { isString } = require('playwright/lib/server/dom.js')25const { isNumber } = require('playwright/lib/server/dom.js')26const { isBoolean } = require('playwright/lib/server/dom.js')27const { isObject } = require('playwright/lib/server/dom.js')28const { isRegExp } = require('playwright/lib/server/dom.js')29const { isPromise } = require('playwright/lib/server/dom.js')30const { isMap } = require('playwright/lib/server/dom.js')31const { isSet } = require('playwright/lib/server/dom.js')32const { isDate } = require('playwright/lib/server/dom.js')

Using AI Code Generation

1const { chromium } = require('playwright');2const fs = require('fs');3(async () => {4  const browser = await chromium.launch({ headless: false });5  const page = await browser.newPage();6  await page.waitForSelector('h1');7  await page.evaluate(() => {8    const fiber = window.__REACT_DEVTOOLS_GLOBAL_HOOK__._fiberRoots.values().next().value.current;9    const instance = fiber.stateNode;10    instance.finalizeInitialChildren();11  });12  const html = await page.content();13  fs.writeFileSync('react.html', html);14  await browser.close();15})();

StackOverFlow community discussions

Questions

Discussion

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

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

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

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

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

Blogs

Check out the latest blogs from LambdaTest on this topic:

Test Optimization for Continuous Integration

“Test frequently and early.” If you’ve been following my testing agenda, you’re probably sick of hearing me repeat that. However, it is making sense that if your tests detect an issue soon after it occurs, it will be easier to resolve. This is one of the guiding concepts that makes continuous integration such an effective method. I’ve encountered several teams who have a lot of automated tests but don’t use them as part of a continuous integration approach. There are frequently various reasons why the team believes these tests cannot be used with continuous integration. Perhaps the tests take too long to run, or they are not dependable enough to provide correct results on their own, necessitating human interpretation.

Difference Between Web And Mobile Application Testing

Smartphones have changed the way humans interact with technology. Be it travel, fitness, lifestyle, video games, or even services, it’s all just a few touches away (quite literally so). We only need to look at the growing throngs of smartphone or tablet users vs. desktop users to grasp this reality.

Introducing LambdaTest Analytics: Test Reporting Made Awesome ????

Collecting and examining data from multiple sources can be a tedious process. The digital world is constantly evolving. To stay competitive in this fast-paced environment, businesses must frequently test their products and services. While it’s easy to collect raw data from multiple sources, it’s far more complex to interpret it properly.

The Top 52 Selenium Open Source Projects On GitHub

Selenium, a project hosted by the Apache Software Foundation, is an umbrella open-source project comprising a variety of tools and libraries for test automation. Selenium automation framework enables QA engineers to perform automated web application testing using popular programming languages like Python, Java, JavaScript, C#, Ruby, and PHP.

How To Automate Toggle Buttons In Selenium Java

If you pay close attention, you’ll notice that toggle switches are all around us because lots of things have two simple states: either ON or OFF (in binary 1 or 0).

Playwright tutorial

LambdaTest’s Playwright tutorial will give you a broader idea about the Playwright automation framework, its unique features, and use cases with examples to exceed your understanding of Playwright testing. This tutorial will give A to Z guidance, from installing the Playwright framework to some best practices and advanced concepts.

Chapters:

What is Playwright : Playwright is comparatively new but has gained good popularity. Get to know some history of the Playwright with some interesting facts connected with it.
How To Install Playwright : Learn in detail about what basic configuration and dependencies are required for installing Playwright and run a test. Get a step-by-step direction for installing the Playwright automation framework.
Playwright Futuristic Features: Launched in 2020, Playwright gained huge popularity quickly because of some obliging features such as Playwright Test Generator and Inspector, Playwright Reporter, Playwright auto-waiting mechanism and etc. Read up on those features to master Playwright testing.
What is Component Testing: Component testing in Playwright is a unique feature that allows a tester to test a single component of a web application without integrating them with other elements. Learn how to perform Component testing on the Playwright automation framework.
Inputs And Buttons In Playwright: Every website has Input boxes and buttons; learn about testing inputs and buttons with different scenarios and examples.
Functions and Selectors in Playwright: Learn how to launch the Chromium browser with Playwright. Also, gain a better understanding of some important functions like “BrowserContext,” which allows you to run multiple browser sessions, and “newPage” which interacts with a page.
Handling Alerts and Dropdowns in Playwright : Playwright interact with different types of alerts and pop-ups, such as simple, confirmation, and prompt, and different types of dropdowns, such as single selector and multi-selector get your hands-on with handling alerts and dropdown in Playright testing.
Playwright vs Puppeteer: Get to know about the difference between two testing frameworks and how they are different than one another, which browsers they support, and what features they provide.
Run Playwright Tests on LambdaTest: Playwright testing with LambdaTest leverages test performance to the utmost. You can run multiple Playwright tests in Parallel with the LammbdaTest test cloud. Get a step-by-step guide to run your Playwright test on the LambdaTest platform.
Playwright Python Tutorial: Playwright automation framework support all major languages such as Python, JavaScript, TypeScript, .NET and etc. However, there are various advantages to Python end-to-end testing with Playwright because of its versatile utility. Get the hang of Playwright python testing with this chapter.
Playwright End To End Testing Tutorial: Get your hands on with Playwright end-to-end testing and learn to use some exciting features such as TraceViewer, Debugging, Networking, Component testing, Visual testing, and many more.
Playwright Video Tutorial: Watch the video tutorials on Playwright testing from experts and get a consecutive in-depth explanation of Playwright automation testing.