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How to use rethrowCaughtError method in Playwright Internal

Best JavaScript code snippet using playwright-internal

ReactErrorUtils-test.js

...46        'foo',47        callback,48        null,49      );50      expect(() => ReactErrorUtils.rethrowCaughtError()).toThrow(err);51    });52    it(`should call the callback the passed arguments (${environment})`, () => {53      var callback = jest.fn();54      ReactErrorUtils.invokeGuardedCallback(55        'foo',56        callback,57        null,58        'arg1',59        'arg2',60      );61      expect(callback).toBeCalledWith('arg1', 'arg2');62    });63    it(`should call the callback with the provided context (${environment})`, () => {64      var context = {didCall: false};65      ReactErrorUtils.invokeGuardedCallback(66        'foo',67        function() {68          this.didCall = true;69        },70        context,71      );72      expect(context.didCall).toBe(true);73    });74    it(`should return a caught error (${environment})`, () => {75      const error = new Error();76      const returnValue = ReactErrorUtils.invokeGuardedCallback(77        'foo',78        function() {79          throw error;80        },81        null,82        'arg1',83        'arg2',84      );85      expect(returnValue).toBe(error);86    });87    it(`should return null if no error is thrown (${environment})`, () => {88      var callback = jest.fn();89      const returnValue = ReactErrorUtils.invokeGuardedCallback(90        'foo',91        callback,92        null,93      );94      expect(returnValue).toBe(null);95    });96    it(`can nest with same debug name (${environment})`, () => {97      const err1 = new Error();98      let err2;99      const err3 = new Error();100      const err4 = ReactErrorUtils.invokeGuardedCallback(101        'foo',102        function() {103          err2 = ReactErrorUtils.invokeGuardedCallback(104            'foo',105            function() {106              throw err1;107            },108            null,109          );110          throw err3;111        },112        null,113      );114      expect(err2).toBe(err1);115      expect(err4).toBe(err3);116    });117    it(`does not return nested errors (${environment})`, () => {118      const err1 = new Error();119      let err2;120      const err3 = ReactErrorUtils.invokeGuardedCallback(121        'foo',122        function() {123          err2 = ReactErrorUtils.invokeGuardedCallback(124            'foo',125            function() {126              throw err1;127            },128            null,129          );130        },131        null,132      );133      expect(err3).toBe(null); // Returns null because inner error was already captured134      expect(err2).toBe(err1);135    });136    it(`can be shimmed (${environment})`, () => {137      const ops = [];138      // Override the original invokeGuardedCallback139      ReactErrorUtils.invokeGuardedCallback = function(name, func, context, a) {140        ops.push(a);141        try {142          func.call(context, a);143        } catch (error) {144          return error;145        }146        return null;147      };148      var err = new Error('foo');149      var callback = function() {150        throw err;151      };152      ReactErrorUtils.invokeGuardedCallbackAndCatchFirstError(153        'foo',154        callback,155        null,156        'somearg',157      );158      expect(() => ReactErrorUtils.rethrowCaughtError()).toThrow(err);159      // invokeGuardedCallbackAndCatchFirstError and rethrowCaughtError close160      // over ReactErrorUtils.invokeGuardedCallback so should use the161      // shimmed version.162      expect(ops).toEqual(['somearg']);163    });164  }...

ReactErrorUtils.js

Source: ReactErrorUtils.js

1/**2 * Copyright 2013-present, Facebook, Inc.3 * All rights reserved.4 *5 * This source code is licensed under the BSD-style license found in the6 * LICENSE file in the root directory of this source tree. An additional grant7 * of patent rights can be found in the PATENTS file in the same directory.8 *9 * @providesModule ReactErrorUtils10 * @flow11 */12'use strict';13const invariant = require('fbjs/lib/invariant');14let caughtError = null;15let invokeGuardedCallback = function(name, func, context, a, b, c, d, e, f) {16  const funcArgs = Array.prototype.slice.call(arguments, 3);17  try {18    func.apply(context, funcArgs);19  } catch (error) {20    return error;21  }22  return null;23};24if (__DEV__) {25  /**26   * To help development we can get better devtools integration by simulating a27   * real browser event.28   */29  if (30    typeof window !== 'undefined' &&31    typeof window.dispatchEvent === 'function' &&32    typeof document !== 'undefined' &&33    typeof document.createEvent === 'function'34  ) {35    const fakeNode = document.createElement('react');36    let depth = 0;37    invokeGuardedCallback = function(name, func, context, a, b, c, d, e, f) {38      depth++;39      const thisDepth = depth;40      const funcArgs = Array.prototype.slice.call(arguments, 3);41      const boundFunc = function() {42        func.apply(context, funcArgs);43      };44      let fakeEventError = null;45      const onFakeEventError = function(event) {46        // Don't capture nested errors47        if (depth === thisDepth) {48          fakeEventError = event.error;49        }50      };51      const evtType = `react-${name ? name : 'invokeguardedcallback'}-${depth}`;52      window.addEventListener('error', onFakeEventError);53      fakeNode.addEventListener(evtType, boundFunc, false);54      const evt = document.createEvent('Event');55      evt.initEvent(evtType, false, false);56      fakeNode.dispatchEvent(evt);57      fakeNode.removeEventListener(evtType, boundFunc, false);58      window.removeEventListener('error', onFakeEventError);59      depth--;60      return fakeEventError;61    };62  }63}64let rethrowCaughtError = function() {65  if (caughtError) {66    const error = caughtError;67    caughtError = null;68    throw error;69  }70};71/**72 * Call a function while guarding against errors that happens within it.73 * Returns an error if it throws, otherwise null.74 *75 * @param {String} name of the guard to use for logging or debugging76 * @param {Function} func The function to invoke77 * @param {*} context The context to use when calling the function78 * @param {...*} args Arguments for function79 */80const ReactErrorUtils = {81  injection: {82    injectErrorUtils(injectedErrorUtils: Object) {83      invariant(84        typeof injectedErrorUtils.invokeGuardedCallback === 'function',85        'Injected invokeGuardedCallback() must be a function.',86      );87      invokeGuardedCallback = injectedErrorUtils.invokeGuardedCallback;88    },89  },90  invokeGuardedCallback: function<A, B, C, D, E, F, Context>(91    name: string | null,92    func: (a: A, b: B, c: C, d: D, e: E, f: F) => void,93    context: Context,94    a: A,95    b: B,96    c: C,97    d: D,98    e: E,99    f: F,100  ): Error | null {101    return invokeGuardedCallback.apply(this, arguments);102  },103  /**104   * Same as invokeGuardedCallback, but instead of returning an error, it stores105   * it in a global so it can be rethrown by `rethrowCaughtError` later.106   *107   * @param {String} name of the guard to use for logging or debugging108   * @param {Function} func The function to invoke109   * @param {*} context The context to use when calling the function110   * @param {...*} args Arguments for function111   */112  invokeGuardedCallbackAndCatchFirstError: function<A, B, C, D, E, F, Context>(113    name: string | null,114    func: (a: A, b: B, c: C, d: D, e: E, f: F) => void,115    context: Context,116    a: A,117    b: B,118    c: C,119    d: D,120    e: E,121    f: F,122  ): void {123    const error = ReactErrorUtils.invokeGuardedCallback.apply(this, arguments);124    if (error !== null && caughtError === null) {125      caughtError = error;126    }127  },128  /**129   * During execution of guarded functions we will capture the first error which130   * we will rethrow to be handled by the top level error handler.131   */132  rethrowCaughtError: function() {133    return rethrowCaughtError.apply(this, arguments);134  },135};...

EventBatching.js

Source: EventBatching.js

...52    'processEventQueue(): Additional events were enqueued while processing ' +53      'an event queue. Support for this has not yet been implemented.',54  );55  // This would be a good time to rethrow if any of the event handlers threw.56  rethrowCaughtError();...

cc6960ReactErrorUtils.js

Source: cc6960ReactErrorUtils.js

...15}16var ReactErrorUtils={17invokeGuardedCallback:invokeGuardedCallback,18invokeGuardedCallbackWithCatch:invokeGuardedCallback,19rethrowCaughtError:function rethrowCaughtError(){20if(caughtError){21var error=caughtError;22caughtError=null;23throw error;24}25}};26if(__DEV__){27if(typeof window!=='undefined'&&28typeof window.dispatchEvent==='function'&&29typeof document!=='undefined'&&30typeof document.createEvent==='function'){31var fakeNode=document.createElement('react');32ReactErrorUtils.invokeGuardedCallback=function(33name,...

ee64dbReactErrorUtils.js

Source: ee64dbReactErrorUtils.js

...15}16var ReactErrorUtils={17invokeGuardedCallback:invokeGuardedCallback,18invokeGuardedCallbackWithCatch:invokeGuardedCallback,19rethrowCaughtError:function rethrowCaughtError(){20if(caughtError){21var error=caughtError;22caughtError=null;23throw error;24}25}};26if(__DEV__){27if(typeof window!=='undefined'&&28typeof window.dispatchEvent==='function'&&29typeof document!=='undefined'&&30typeof document.createEvent==='function'){31var fakeNode=document.createElement('react');32ReactErrorUtils.invokeGuardedCallback=function(33name,...

Using AI Code Generation

1const { InternalError } = require('playwright/lib/server/errors');2const { rethrowCaughtError } = require('playwright/lib/server/progress');3const { InternalError } = require('playwright/lib/server/errors');4const { rethrowCaughtError } = require('playwright/lib/server/progress');5const { InternalError } = require('playwright/lib/server/errors');6const { rethrowCaughtError } = require('playwright/lib/server/progress');7const { InternalError } = require('playwright/lib/server/errors');8const { rethrowCaughtError } = require('playwright/lib/server/progress');9const { InternalError } = require('playwright/lib/server/errors');10const { rethrowCaughtError } = require('playwright/lib/server/progress');11const { InternalError } = require('playwright/lib/server/errors');12const { rethrowCaughtError } = require('playwright/lib/server/progress');13const { InternalError } = require('playwright/lib/server/errors');14const { rethrowCaughtError } = require('playwright/lib/server/progress');15const { InternalError } = require('playwright/lib/server/errors');16const { rethrowCaughtError } = require('playwright/lib/server/progress');17const { InternalError } = require('playwright/lib/server/errors');18const { rethrowCaughtError } = require('playwright/lib/server/progress');19const { InternalError } = require('playwright/lib/server/errors');20const { rethrowCaughtError } = require('playwright/lib/server/progress');21const { InternalError } = require('playwright/lib/server/errors');22const { rethrowCaughtError } = require('playwright/lib/server/progress');

Using AI Code Generation

1const { Playwright } = require('playwright');2const { InternalError } = Playwright;3try {4  await page.click('button');5} catch (e) {6  if (e instanceof InternalError) {7    e.rethrowCaughtError();8  }9}10const { Playwright } = require('playwright');11const { InternalError } = Playwright;12try {13  await page.click('button');14} catch (e) {15  if (e instanceof InternalError) {16    e.rethrowCaughtError();17  }18}19const { Playwright } = require('playwright');20const { InternalError } = Playwright;21try {22  await page.click('button');23} catch (e) {24  if (e instanceof InternalError) {25    e.rethrowCaughtError();26  }27}28const { Playwright } = require('playwright');29const { InternalError } = Playwright;30try {31  await page.click('button');32} catch (e) {33  if (e instanceof InternalError) {34    e.rethrowCaughtError();35  }36}37const { Playwright } = require('playwright');38const { InternalError } = Playwright;39try {40  await page.click('button');41} catch (e) {42  if (e instanceof InternalError) {43    e.rethrowCaughtError();44  }45}46const { Playwright } = require('playwright');47const { InternalError } = Playwright;48try {49  await page.click('button');50} catch (e) {51  if (e instanceof InternalError) {52    e.rethrowCaughtError();53  }54}55const { Playwright } = require('playwright');56const { InternalError } = Playwright;57try {58  await page.click('button');59} catch (e) {60  if (e instanceof

Using AI Code Generation

1const { InternalError } = require('playwright/lib/server/errors');2try {3  throw new InternalError('error message');4} catch (e) {5  InternalError.rethrowCaughtError(e);6}7const { Error } = require('playwright/lib/server/errors');8try {9  throw new Error('error message');10} catch (e) {11  Error.rethrowCaughtError(e);12}13const { TimeoutError } = require('playwright/lib/server/errors');14try {15  throw new TimeoutError('error message');16} catch (e) {17  TimeoutError.rethrowCaughtError(e);18}19const { WaitTaskTimeoutError } = require('playwright/lib/server/errors');20try {21  throw new WaitTaskTimeoutError('error message');22} catch (e) {23  WaitTaskTimeoutError.rethrowCaughtError(e);24}25const { ValidationError } = require('playwright/lib/server/errors');26try {27  throw new ValidationError('error message');28} catch (e) {29  ValidationError.rethrowCaughtError(e);30}31const { AssertionError } = require('playwright/lib/server/errors');32try {33  throw new AssertionError('error message');34} catch (e) {35  AssertionError.rethrowCaughtError(e);36}37const { BrowserContextError } = require('playwright/lib/server/errors');38try {39  throw new BrowserContextError('error message');40} catch (e) {41  BrowserContextError.rethrowCaughtError(e);42}43const { BrowserError } = require('playwright/lib/server/errors');44try {45  throw new BrowserError('error message');46} catch (e) {47  BrowserError.rethrowCaughtError(e);48}49const { BrowserTypeLaunchPersistentContextError } = require('playwright/lib/server/errors');50try {51  throw new BrowserTypeLaunchPersistentContextError('error message');52} catch (

Using AI Code Generation

1const { rethrowCaughtError } = require('playwright/lib/utils/stackTrace');2try {3  throw new Error('error');4} catch (error) {5  rethrowCaughtError(error);6}7const { rethrowCaughtError } = require('playwright/lib/utils/stackTrace');8try {9  throw new Error('error');10} catch (error) {11  rethrowCaughtError(error);12}13const { rethrowCaughtError } = require('playwright/lib/utils/stackTrace');14try {15  throw new Error('error');16} catch (error) {17  rethrowCaughtError(error);18}19const { rethrowCaughtError } = require('playwright/lib/utils/stackTrace');20try {21  throw new Error('error');22} catch (error) {23  rethrowCaughtError(error);24}25const { rethrowCaughtError } = require('playwright/lib/utils/stackTrace');26try {27  throw new Error('error');28} catch (error) {29  rethrowCaughtError(error);30}31const { rethrowCaughtError } = require('playwright/lib/utils/stackTrace');32try {33  throw new Error('error');34} catch (error) {35  rethrowCaughtError(error);36}37const { rethrowCaughtError } = require('playwright/lib/utils/stackTrace');38try {39  throw new Error('error');40} catch (error) {41  rethrowCaughtError(error);42}43const { rethrowCaughtError } = require('playwright/lib/utils/stackTrace');44try {45  throw new Error('error');46} catch (error) {47  rethrowCaughtError(error);48}

Using AI Code Generation

1const { InternalError } = require('playwright/lib/utils/internalError');2const { rethrowCaughtError } = new InternalError();3try {4    await page.click('button');5} catch (err) {6    rethrowCaughtError(err);7}8    at Page._onClose (/Users/username/myproject/node_modules/playwright/lib/server/page.js:106:15)9    at CDPSession.Page.client.on.event (/Users/username/myproject/node_modules/playwright/lib/server/page.js:84:59)10    at CDPSession.emit (events.js:315:20)11    at CDPSession._onMessage (/Users/username/myproject/node_modules/playwright/lib/server/cdpsession.js:123:14)12    at WebSocketTransport._ws.addEventListener.event (/Users/username/myproject/node_modules/playwright/lib/server/webSocketTransport.js:71:24)13    at WebSocket.onMessage (/Users/username/myproject/node_modules/ws/lib/event-target.js:132:16)14    at WebSocket.emit (events.js:315:20)15    at Receiver.receiverOnMessage (/Users/username/myproject/node_modules/ws/lib/websocket.js:789:20)16    at Receiver.emit (events.js:315:20)17    at Receiver.dataMessage (/Users/username/myproject/node_modules/ws/lib/receiver.js:437:14)18    at Receiver.getData (/Users/username/myproject/node_modules/ws/lib/receiver.js:367:17)19    at Receiver.startLoop (/Users/username/myproject/node_modules/ws/lib/receiver.js:143:22)20    at Receiver._write (/Users/username/myproject/node_modules/ws/lib/receiver.js:78:10)21    at doWrite (_

Using AI Code Generation

1const { InternalError } = require('playwright');2const { rethrowCaughtError } = InternalError.prototype;3const error = new Error('error');4const caughtError = new InternalError('caught', error);5rethrowCaughtError.call(caughtError);6const { InternalError } = require('playwright');7const { getError } = InternalError.prototype;8const error = new Error('error');9const caughtError = new InternalError('caught', error);10const rethrownError = getError.call(caughtError);11console.log(rethrownError);12const { TimeoutError } = require('playwright');13const { getError } = TimeoutError.prototype;14const error = new Error('error');15const caughtError = new TimeoutError('caught', error);16const rethrownError = getError.call(caughtError);17console.log(rethrownError);18const { Error } = require('playwright');19const { getError } = Error.prototype;20const error = new Error('error');21const caughtError = new Error('caught', error);22const rethrownError = getError.call(caughtError);23console.log(rethrownError);24const { Error } = require('playwright');25const { getError } = Error.prototype;26const error = new Error('error');27const caughtError = new Error('caught', error);28const rethrownError = getError.call(caughtError);29console.log(rethrownError);30const { Error } = require('playwright');31const { getError } = Error.prototype;32const error = new Error('error');33const caughtError = new Error('caught', error);34const rethrownError = getError.call(caughtError);35console.log(rethrownError);36const { Error } = require('playwright');37const { getError } = Error.prototype;38const error = new Error('error');39const caughtError = new Error('caught', error);40const rethrownError = getError.call(caughtError);41console.log(rethrownError);42const { Error } = require('playwright

Using AI Code Generation

1const { InternalError } = require("playwright-core/lib/utils/stackTrace");2const error = new Error("Test error");3const internalError = new InternalError(error);4console.log(internalError.stack);5const { InternalError } = require("playwright-core/lib/utils/stackTrace");6const error = new Error("Test error");7const internalError = new InternalError(error);8console.log(internalError.stack);9const { InternalError } = require("playwright-core/lib/utils/stackTrace");10const error = new Error("Test error");11const internalError = new InternalError(error);12console.log(internalError.stack);13const { InternalError } = require("playwright-core/lib/utils/stackTrace");14const error = new Error("Test error");15const internalError = new InternalError(error);16console.log(internalError.stack);17const { InternalError } = require("playwright-core/lib/utils/stackTrace");18const error = new Error("Test error");19const internalError = new InternalError(error);20console.log(internalError.stack);21const { InternalError } = require("playwright-core/lib/utils/stackTrace");22const error = new Error("Test error");23const internalError = new InternalError(error);24console.log(internalError.stack);25const { InternalError } = require("playwright-core/lib/utils/stackTrace");26const error = new Error("Test error");27const internalError = new InternalError(error);28console.log(internalError.stack);29const { InternalError } = require("playwright-core/lib/utils/stackTrace");30const error = new Error("Test error");31const internalError = new InternalError(error);32console.log(internalError.stack);33const { InternalError } = require("playwright-core/lib/utils/stackTrace");34const error = new Error("Test error");35const internalError = new InternalError(error);36console.log(internalError.stack

Using AI Code Generation

1const {chromium} = require('playwright');2const {InternalError} = require('playwright/lib/utils/stackTrace');3const {TestServer} = require('playwright/test/server/testServer');4const {expect} = require('chai');5const {describe, it} = require('mocha');6(async () => {7  const browser = await chromium.launch();8  const context = await browser.newContext();9  const page = await context.newPage();10  const server = await TestServer.create();11  server.setRoute('/empty.html', (req, res) => {12    res.statusCode = 500;13    res.end();14  });15  try {16    await page.goto(server.EMPTY_PAGE);17  } catch (e) {18    InternalError.rethrowCaughtError(e);19  }20  await server.stop();21  await browser.close();22})();

StackOverFlow community discussions

Questions

Discussion

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

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

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

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

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

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

Blogs

Check out the latest blogs from LambdaTest on this topic:

An Interactive Guide To CSS Hover Effects

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A Complete Guide To CSS Houdini

As a developer, checking the cross browser compatibility of your CSS properties is of utmost importance when building your website. I have often found myself excited to use a CSS feature only to discover that it’s still not supported on all browsers. Even if it is supported, the feature might be experimental and not work consistently across all browsers. Ask any front-end developer about using a CSS feature whose support is still in the experimental phase in most prominent web browsers. ????

How To Test React Native Apps On iOS And Android

As everyone knows, the mobile industry has taken over the world and is the fastest emerging industry in terms of technology and business. It is possible to do all the tasks using a mobile phone, for which earlier we had to use a computer. According to Statista, in 2021, smartphone vendors sold around 1.43 billion smartphones worldwide. The smartphone penetration rate has been continuously rising, reaching 78.05 percent in 2020. By 2025, it is expected that almost 87 percent of all mobile users in the United States will own a smartphone.

Do you possess the necessary characteristics to adopt an Agile testing mindset?

To understand the agile testing mindset, we first need to determine what makes a team “agile.” To me, an agile team continually focuses on becoming self-organized and cross-functional to be able to complete any challenge they may face during a project.

Best Mobile App Testing Framework for Android and iOS Applications

This article is a part of our Content Hub. For more in-depth resources, check out our content hub on Mobile App Testing Tutorial.

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.