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How to use isValidContainer method in Playwright Internal

Best JavaScript code snippet using playwright-internal

ReactDOMLegacy.js

Source:ReactDOMLegacy.js

...137  container: Container,138  callback: ?Function,139) {140  invariant(141    isValidContainer(container),142    'Target container is not a DOM element.',143  );144  // TODO: throw or warn if we couldn't hydrate?145  return legacyRenderSubtreeIntoContainer(146    null,147    element,148    container,149    true,150    callback,151  );152}153export function render(154  element: React$Element<any>,155  container: Container,156  callback: ?Function,157) {158  invariant(159    isValidContainer(container),160    'Target container is not a DOM element.',161  );162  return legacyRenderSubtreeIntoContainer(163    null,164    element,165    container,166    false,167    callback,168  );169}170export function unstable_renderSubtreeIntoContainer(171  parentComponent: React$Component<any, any>,172  element: React$Element<any>,173  containerNode: Container,174  callback: ?Function,175) {176  invariant(177    isValidContainer(containerNode),178    'Target container is not a DOM element.',179  );180  invariant(181    parentComponent != null && hasInstance(parentComponent),182    'parentComponent must be a valid React Component',183  );184  return legacyRenderSubtreeIntoContainer(185    parentComponent,186    element,187    containerNode,188    false,189    callback,190  );191}192export function unmountComponentAtNode(container: Container) {193  invariant(194    isValidContainer(container),195    'unmountComponentAtNode(...): Target container is not a DOM element.',196  );197  if (container._reactRootContainer) {198    // Unmount should not be batched.199    unbatchedUpdates(() => {200      legacyRenderSubtreeIntoContainer(null, null, container, false, () => {201        // $FlowFixMe This should probably use `delete container._reactRootContainer`202        container._reactRootContainer = null;203        unmarkContainerAsRoot(container);204      });205    });206    // If you call unmountComponentAtNode twice in quick succession, you'll207    // get `true` twice. That's probably fine?208    return true;...

sortable.js

Source:sortable.js

...69  function dragStart(e) {70    e.originalEvent.dataTransfer.effectAllowed = 'move';71  }72  function dragOver(e) {73    if (!isValidContainer(e.currentTarget)) {74      return false;75    }76    var t = $(e.currentTarget);77    if (!t.is(moving.item)) { // not the same object78      if (isBefore(moving.item, t)) {79        moving.item.insertAfter(t);80      } else {81        moving.item.insertBefore(t);82      }83    }84  }85  /**86   * Returns true iff el is an element inside an appropriate container for the87   * current drag.88   */89  function isValidContainer(el) {90    var container = $(el).closest('.' + CONTAINER_CLASS);91    var group = container.data(GROUP_KEY);92    if (!container.length) {93      return false; // not a container at all94    }95    if (container.is(moving.src)) {96      return true; // we're in the original container97    }98    if (!group) {99      return false; // current container isn't part of any group100    }101    if (group == moving.src.data(GROUP_KEY)) {102      return true; // current container is in the correct group103    }104    return false;105  }106  function isBefore(a, b) {107    while (a.length && !a.is(b)) {108      a = a.next();109    }110    return a.length;111  }112  function cleanup() {113    moving.item114      .closest('.' + CONTAINER_CLASS + ' > *')115      .removeAttr('draggable')116      .css('opacity', '');117    moving = {};118  }119  function mouseUp() {120    cleanup();121  }122  function dragEnd(e) {123    var over = document.elementFromPoint(coords.x, coords.y);124    var trashSel = moving.src.data(TRASH_KEY);125    var trash = $(over).closest(trashSel);126    if (trash.length) {127      moving.item.remove();128    } else if (!isValidContainer(over)) {129      moving.item.detach().insertAt(moving.src, moving.index);130    }131    cleanup();132  }...

Uploady.js

Source:Uploady.js

1// @flow2import React, { forwardRef, memo, useRef } from "react";3import ReactDOM from "react-dom";4import { invariant, hasWindow } from "@rpldy/shared";5import { NoDomUploady, useUploadOptions } from "@rpldy/shared-ui";6import type { UploadyProps } from "@rpldy/shared-ui";7type FileInputPortalProps = {|8    container: ?HTMLElement,9    multiple: boolean,10    capture: ?string,11    accept: ?string,12    webkitdirectory: ?boolean,13    id: ?string,14    style: Object,15    noPortal: boolean,16|};17const NO_CONTAINER_ERROR_MSG = "Uploady - Container for file input must be a valid dom element";18const renderInput = (inputProps, instanceOptions, ref) => <input19    {...inputProps}20    name={instanceOptions.inputFieldName}21    type="file"22    ref={ref}23/>;24const renderInPortal = (container, isValidContainer, inputProps, instanceOptions, ref) =>25    container && isValidContainer ?26        ReactDOM.createPortal(renderInput(inputProps, instanceOptions, ref), container) :27        null;28const FileInputField = memo(forwardRef(({ container, noPortal, ...inputProps }: FileInputPortalProps, ref) => {29    const instanceOptions = useUploadOptions();30    const isValidContainer = container && container.nodeType === 1;31    invariant(32        isValidContainer || !hasWindow(),33        NO_CONTAINER_ERROR_MSG34    );35    // In DEV - SSR React will warn on mismatch between client&server :( -36    // https://github.com/facebook/react/issues/1261537    // https://github.com/facebook/react/issues/1309738    return noPortal ?39        renderInput(inputProps, instanceOptions, ref) :40        renderInPortal(container, isValidContainer, inputProps, instanceOptions, ref);41}));42const Uploady = (props: UploadyProps): React$Element<typeof NoDomUploady> => {43    const {44        multiple = true,45        capture,46        accept,47        webkitdirectory,48        children,49        inputFieldContainer,50        customInput,51        fileInputId,52        noPortal  = false,53        ...noDomProps54    } = props;55    const container = !customInput ?56        (inputFieldContainer || (hasWindow() ? document.body : null)) : null;57    const internalInputFieldRef = useRef<?HTMLInputElement>();58    return <NoDomUploady {...noDomProps} inputRef={internalInputFieldRef} >59        {!customInput ? <FileInputField60            container={container}61            multiple={multiple}62            capture={capture}63            accept={accept}64            webkitdirectory={webkitdirectory}65            style={{ display: "none" }}66            ref={internalInputFieldRef}67            id={fileInputId}68            noPortal={noPortal}69        /> : null}70        {children}71    </NoDomUploady>;72};...

EventContainer.js

Source:EventContainer.js

1function EventContainer(arrEventNames)2{3	if (IsUndefined(arrEventNames) || IsUndefined(arrEventNames.length))4	{5		this.ThrowArgumentException("arrEventNames must be a valid array!");6		return null;7	}8	// init type manager, required for inheritance9	this.InitTypeManager(arguments);10	// inherit this object from other classes11	arguments.Call(BaseEventContainer);12	// copies a reference of the protected members for using from outside the constructor13	var _protected		= arguments.Protected;14	with (_protected.BaseEventContainer)15	{16		EventTypes	= new Array();17		EventNames	= arrEventNames;18		CreateEventSubjects(EventTypes, EventNames);19	}20	// attaches an event function to the specified container.21	// if the event was added successfully, this function returns the index22	// of the new EventItem in the strName container, otherwise it returns null23	this.Attach = function(strContainerName, objEvent, strFunctionName)24	{25		if (_protected.BaseEventContainer.IsValidContainer(strContainerName))26		{27			return _protected.BaseEventContainer.EventTypes[strContainerName].Attach(objEvent, strFunctionName);28		}29		return null;30	}31	// detaches an event function from the specified container with the given name32	this.Detach = function(strContainerName, strFunctionName)33	{34		if (_protected.BaseEventContainer.IsValidContainer(strContainerName))35		{36			_protected.BaseEventContainer.EventTypes[strContainerName].Detach(strFunctionName);37		}38	}39	// detaches an event function from the specified container with the given index40	this.DetachByIndex = function(strContainerName, intFunctionIndex)41	{42		if (_protected.BaseEventContainer.IsValidContainer(strContainerName))43		{44			_protected.BaseEventContainer.EventTypes[strContainerName].DetachByIndex(intFunctionIndex);45		}46	}47	// fires an event and creates an EventArgument object48	// this function should not be used from global code49	this.FireUpdate = function(strContainerName, objEventArgument)50	{51		if (_protected.BaseEventContainer.IsValidContainer(strContainerName))52		{53			_protected.BaseEventContainer.EventTypes[strContainerName].FireUpdate(objEventArgument);54		}55	}...

FormBuilder.js

Source:FormBuilder.js

...5import availableOptions from "./utils/availableOptions.js";6export default function FormBuilder(selector, options, onSubmit) {7    documentReady(function () {8        let element = document.querySelector(selector);9        if (!isValidContainer(element)) {10            {11                throw Error("Target container is not a DOM element.");12            }13        }14        if (!checkIfObjectIsArray(options)) {15            {16                throw Error("Options are not valid");17            }18        }19        insertForm(element, "builder_form", onSubmit);20        let form = document.getElementsByName("builder_form")[0];21        if (form) {22            options.forEach((item) => {23                availableOptions[item.inputType](item, form);...

source-code-snippet.js

Source:source-code-snippet.js

1function isValidContainer(node) {2    return !!(node && 3      (node.nodeType === ELEMENT_NODE 4        || node.nodeType === DOCUMENT_NODE 5        || node.nodeType === DOCUMENT_FRAGMENT_NODE 6        // If you want to know how to use react-mount-point-unstable, check out my twitter thread7        // https://twitter.com/fromaline/status/1487059240468590596  8        || node.nodeType === COMMENT_NODE && node.nodeValue === ' react-mount-point-unstable ')9    );10}11function isContainerMarkedAsRoot(node) {12  // internalContainerInstanceKey equals to __reactContainer + generated unique hash13  return !!node[internalContainerInstanceKey];14}15function render(element, container, callback) {16  if (!isValidContainer(container)) {17    {18      throw Error( "Target container is not a DOM element." );19    }20  }21  {22    var isModernRoot = isContainerMarkedAsRoot(container) && container._reactRootContainer === undefined;23    if (isModernRoot) {24      error('You are calling ReactDOM.render() on a container that was previously ' + 'passed to ReactDOM.createRoot(). This is not supported. ' + 'Did you mean to call root.render(element)?');25    }26  }27  return legacyRenderSubtreeIntoContainer(null, element, container, false, callback);...

validation.js

Source:validation.js

...8			// Validate the container9			if(recursive === false) {10				formValidation.validateContainer($container);	11			}12			var isValidContainer = formValidation.isValidContainer($container);13			if (isValidContainer === false || isValidContainer === null) {14			    if (isValidContainer === false)15			    	$.unblockUI();16			    17			    // Stop submission because of validation error.18			    return isValidContainer;19			} else {20				return true;21				22			}23		}24		25	}26	function validationAddFields($fields) {...

ReactDom.js

Source:ReactDom.js

...8} from "./utils";9import diff from "./diff";10import { readyWorks } from "./top";11export function render(vnode, container, callback) {12	if (!isValidContainer(container)) {13		throw new Error("Target container is not a DOM element.asda");14	}15	let dom;16	if (container._reactRootContainer) {17		dom = diff(container._reactRootContainer, vnode, container);18	} else {19		dom = createDomNode(vnode);20		container.appendChild(dom);21	}22	if (isFunction(callback)) {23		callback.call(dom);24	}25	readyWorks.flushWorks();26	container._reactRootContainer = vnode;27	return isComposite(vnode) ? vnode.component : dom;28}29export function findDOMNode(componentOrVnode) {30	if (isVnode(componentOrVnode)) {31		return componentOrVnode.dom;32	} else if (isComponent(componentOrVnode)) {33		return componentOrVnode.vNode.dom;34	} else if (isValidContainer(componentOrVnode)) {35		return componentOrVnode;36	}37	return null;...

Using AI Code Generation

1const { isValidContainer } = require('playwright/lib/internal/frames');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 frame = page.mainFrame();8  const elementHandle = await frame.$('body');9  const result = await isValidContainer(elementHandle);10  console.log(result);11  await browser.close();12})();13Your name to display (optional):

Using AI Code Generation

1const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const page = await browser.newPage();6  const container = await page.$('#hplogo');7  console.log(await isValidContainer(container));8  await browser.close();9})();

Using AI Code Generation

1const { isValidContainer } = require('@playwright/test/lib/server/frames');2const { Frame } = require('@playwright/test/lib/server/frames');3const { ElementHandle } = require('@playwright/test/lib/server/dom');4const frame = new Frame();5const elementHandle = new ElementHandle();6const result = isValidContainer(frame, elementHandle);7console.log(result);8const { isValidContainer } = require('playwright/lib/server/frames');9const { Frame } = require('playwright/lib/server/frames');10const { ElementHandle } = require('playwright/lib/server/dom');11const frame = new Frame();12const elementHandle = new ElementHandle();13const result = isValidContainer(frame, elementHandle);14console.log(result);15const { isValidContainer } = require('playwright/lib/server/frames');16const { Frame } = require('playwright/lib/server/frames');17const { ElementHandle } = require('playwright/lib/server/dom');18const frame = new Frame();19const elementHandle = new ElementHandle();20const result = isValidContainer(frame, elementHandle);21console.log(result);22const { isValidContainer } = require('playwright/lib/server/frames');23const { Frame } = require('playwright/lib/server/frames');24const { ElementHandle } = require('playwright/lib/server/dom');25const frame = new Frame();26const elementHandle = new ElementHandle();27const result = isValidContainer(frame, elementHandle);28console.log(result);29const { isValidContainer } = require('playwright/lib/server/frames');30const { Frame } = require('playwright/lib/server/frames');31const { ElementHandle } = require('playwright/lib/server/dom');32const frame = new Frame();

Using AI Code Generation

1const { isValidContainer } = require('playwright/lib/server/supplements/recorder/frames');2const { chromium } = require('playwright');3const fs = require('fs');4(async () => {5  const browser = await chromium.launch();6  const context = await browser.newContext();7  const page = await context.newPage();8  const element = await page.$('h1');9  console.log(await isValidContainer(element));10  await browser.close();11})();

Using AI Code Generation

1import { isValidContainer } from 'playwright/lib/server/browserType';2import { isValidContainer } from 'playwright/lib/server/browserType';3import { isValidContainer } from 'playwright/lib/server/browserType';4import { isValidContainer } from 'playwright/lib/server/browserType';5import { isValidContainer } from 'playwright/lib/server/browserType';6import { isValidContainer } from 'playwright/lib/server/browserType';7import { isValidContainer } from 'playwright/lib/server/browserType';8import { isValidContainer } from 'playwright/lib/server/browserType';9import { isValidContainer } from 'playwright/lib/server/browserType';10import { isValidContainer } from 'playwright/lib/server/browserType';11import { isValidContainer } from 'playwright/lib/server/browserType';12import { isValidContainer } from 'playwright/lib/server/browserType';13import { isValidContainer } from 'playwright/lib/server/browserType';14import { isValidContainer } from 'playwright/lib/server/browserType';15import { isValidContainer } from 'playwright/lib/server/browserType';16import { isValidContainer } from 'playwright/lib/server/browserType';17import { isValidContainer } from 'playwright/lib/server/browserType';18import { isValidContainer } from 'play

Using AI Code Generation

1const { isValidContainer } = require('playwright/lib/server/dom.js');2const valid = isValidContainer({ name: 'div' });3console.log(valid);4const { isValidSelector } = require('playwright/lib/server/dom.js');5const valid = isValidSelector('div');6console.log(valid);7const { isValidXPath } = require('playwright/lib/server/dom.js');8console.log(valid);9const { isSelectorList } = require('playwright/lib/server/dom.js');10const valid = isSelectorList('div, button');11console.log(valid);12const { isString } = require('playwright/lib/server/dom.js');13const valid = isString('div');14console.log(valid);15const { isStringArray } = require('playwright/lib/server/dom.js');16const valid = isStringArray(['div', 'button']);17console.log(valid);18const { isURL } = require('playwright/lib/server/dom.js');19console.log(valid);20const { isXPath } = require('playwright/lib/server/dom.js');21console.log(valid);22const { isXPathArray } = require('playwright/lib/server/dom.js');23console.log(valid);24const { isXPathList } = require('playwright/lib/server/dom.js');25console.log(valid);26const { isXPathOrString } = require('playwright/lib

Using AI Code Generation

1const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');2const container = document.querySelector('.container');3const isContainerValid = isValidContainer(container);4const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');5const container = document.querySelector('.container');6const isContainerValid = isValidContainer(container);7const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');8const container = document.querySelector('.container');9const isContainerValid = isValidContainer(container);10const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');11const container = document.querySelector('.container');12const isContainerValid = isValidContainer(container);13const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');14const container = document.querySelector('.container');15const isContainerValid = isValidContainer(container);16const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');17const container = document.querySelector('.container');18const isContainerValid = isValidContainer(container);19const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');20const container = document.querySelector('.container');21const isContainerValid = isValidContainer(container);22const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');23const container = document.querySelector('.container');24const isContainerValid = isValidContainer(container);25const { isValidContainer } = require('playwright/lib/server/chromium/crBrowser');26const container = document.querySelector('.container');27const isContainerValid = isValidContainer(container);

Using AI Code Generation

1const { isValidContainer } = require('playwright/lib/utils/validator');2const isValid = isValidContainer('div');3console.log(isValid);4const { isValidContainer } = require('playwright/lib/utils/validator');5const isValid = isValidContainer('div');6console.log(isValid);7const { isValidSelector } = require('playwright/lib/utils/validator');8const isValid = isValidSelector('div');9console.log(isValid);10const { isValidSelector } = require('playwright/lib/utils/validator');11const isValid = isValidSelector('div');12console.log(isValid);

Using AI Code Generation

1const { isValidContainer } = require('@playwright/test');2const container = { name: 'My Container' };3const isValid = isValidContainer(container);4console.log(isValid ? container.name : 'Invalid container');5const { isValidContainer } = require('@playwright/test');6const container = { name: 'My Container' };7const isValid = isValidContainer(container);8console.log(isValid ? container.name : 'Invalid container');9const { isValidContainer } = require('@playwright/test');10const container = { name: 'My Container' };11const isValid = isValidContainer(container);12console.log(isValid ? container.name : 'Invalid container');13const { isValidContainer } = require('@playwright/test');14const container = { name: 'My Container' };15const isValid = isValidContainer(container);16console.log(isValid ? container.name : 'Invalid container');17const { isValidContainer } = require('@playwright/test');18const container = { name: 'My Container' };19const isValid = isValidContainer(container);20console.log(isValid ? container.name : 'Invalid container');21const { isValidContainer } = require('@playwright/test');22const container = { name: 'My Container' };23const isValid = isValidContainer(container);24console.log(isValid ? container.name : 'Invalid container');

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?

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

firefox browser does not start in playwright

Running Playwright in Azure Function

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

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

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:

QA’s and Unit Testing – Can QA Create Effective Unit Tests

Unit testing is typically software testing within the developer domain. As the QA role expands in DevOps, QAOps, DesignOps, or within an Agile team, QA testers often find themselves creating unit tests. QA testers may create unit tests within the code using a specified unit testing tool, or independently using a variety of methods.

[LambdaTest Spartans Panel Discussion]: What Changed For Testing & QA Community And What Lies Ahead

The rapid shift in the use of technology has impacted testing and quality assurance significantly, especially around the cloud adoption of agile development methodologies. With this, the increasing importance of quality and automation testing has risen enough to deliver quality work.

How To Handle Multiple Windows In Selenium Python

Automating testing is a crucial step in the development pipeline of a software product. In an agile development environment, where there is continuous development, deployment, and maintenance of software products, automation testing ensures that the end software products delivered are error-free.

New Year Resolutions Of Every Website Tester In 2020

Were you able to work upon your resolutions for 2019? I may sound comical here but my 2019 resolution being a web developer was to take a leap into web testing in my free time. Why? So I could understand the release cycles from a tester’s perspective. I wanted to wear their shoes and see the SDLC from their eyes. I also thought that it would help me groom myself better as an all-round IT professional.

What is coaching leadership

Coaching is a term that is now being mentioned a lot more in the leadership space. Having grown successful teams I thought that I was well acquainted with this subject.

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.