Discover AI-native insights at Testμ Conference‘25

How to use mountCallback method in Playwright Internal

Best JavaScript code snippet using playwright-internal

superhtml.js

...28  let mountCallback = null;29  // Run mountCallback when component mounted30  componentMounted.promise.then(() => {31    if (mountCallback) {32      mountCallback();33    }34  })35  /*36    Returns a random hash to be used as an HTML element class37    @return {String} resultant hash38  */39  function createRandomClass() {40    return window.btoa(window.crypto.getRandomValues(new Uint32Array(1)));41  }42  /*43    Evaluates a regular expression on a string and returns a match boolean44    45    @param {String} string - input string46    @param {RegExp} regex - regular expression ...

crostini.js

Source:crostini.js

...66          },67        });68        // Continue from fileManagerPrivate.mountCrostiniContainer callback69        // and ensure expected files are shown.70        mountCallback();71        return test.waitForFiles(72            test.TestEntryInfo.getExpectedRows(test.CROSTINI_ENTRY_SET));73      })74      .then(() => {75        // Reset fileManagerPrivate.mountCrostiniContainer and remove mount.76        chrome.fileManagerPrivate.mountCrostiniContainer = oldMount;77        chrome.fileManagerPrivate.removeMount('crostini');78        // Linux Files fake root is shown.79        return test.waitForElement(80            '#directory-tree .tree-item [root-type-icon="crostini"]');81      })82      .then(() => {83        // Downloads folder should be shown when crostini goes away.84        return test.waitForFiles(...

crostini_mount.js

Source:crostini_mount.js

...38  // and add crostini disk mount.39  test.mountCrostini();40  // Continue from fileManagerPrivate.mountCrostini callback41  // and ensure expected files are shown.42  mountCallback();43  await test.waitForFiles(44      test.TestEntryInfo.getExpectedRows(test.BASIC_CROSTINI_ENTRY_SET));45  // Reset fileManagerPrivate.mountCrostini and remove mount.46  chrome.fileManagerPrivate.mountCrostini = oldMount;47  chrome.fileManagerPrivate.removeMount('crostini');48  // Linux Files fake root is shown.49  await test.waitForElement(fakeRoot);50  // MyFiles folder should be shown when crostini goes away.51  await test.waitForFiles(test.TestEntryInfo.getExpectedRows(52      test.BASIC_MY_FILES_ENTRY_SET_WITH_LINUX_FILES));53  done();54};55crostiniMount.testMountCrostiniError = async (done) => {56  const fakeRoot = '#directory-tree [root-type-icon="crostini"]';...

main.js

Source:main.js

1import Vue from 'vue'2import App from './App.vue'3// import router from './router'4// import store from './store'5import ElementUI from 'element-ui'6import 'element-ui/lib/theme-chalk/index.css'7Vue.config.productionTip = false8Vue.use(ElementUI)9// è·åé¡µé¢ç»ä»¶å¯¹è±¡10// const viewsComponentObj = (() => {11//   const views = require.context('@/views', true, /^((?!componen).)+\.vue$/)12//   const viewsComponent = views.keys().map(v => {13//     views(v).default.file = v.replace('./', 'src/views/')14//     return views(v).default15//   })16//   const obj = {}17//   viewsComponent.forEach(v => {18//     obj[v.file] = v19//   })20//   return obj21// })()22// new Vue({23//   router,24//   store,25//   render: h => h(App)26// }).$mount('#app')27if (!window.__INJECTED_PUBLIC_PATH_BY_QIANKUN__) {28  new Vue({29    // router,30    // store,31    render: h => h(App)32  }).$mount('#app')33}34/**35 * bootstrap åªä¼å¨å¾®åºç¨åå§åçæ¶åè°ç¨ä¸æ¬¡ï¼ä¸æ¬¡å¾®åºç¨éæ°è¿å¥æ¶ä¼ç´æ¥è°ç¨ mount é©åï¼ä¸ä¼åéå¤è§¦å bootstrapã36 * éå¸¸æä»¬å¯ä»¥å¨è¿éåä¸äºå¨å±åéçåå§åï¼æ¯å¦ä¸ä¼å¨ unmount é¶æ®µè¢«éæ¯çåºç¨çº§å«çç¼åçã37 */38export async function bootstrap () {39  // å®æ¶ç»å®å¾®åºç¨çhost40  // eslint-disable-next-line41  __webpack_public_path__ = window.__INJECTED_PUBLIC_PATH_BY_QIANKUN__42}43let $vm = null44/**45 * åºç¨æ¯æ¬¡è¿å¥é½ä¼è°ç¨ mount æ¹æ³ï¼éå¸¸æä»¬å¨è¿éè§¦ååºç¨çæ¸²ææ¹æ³46 */47export async function mount (props) {48  const rootDiv = document.createElement('div')49  props.container.appendChild(rootDiv)50  $vm = new Vue({51    el: rootDiv,52    mounted () {53      if (props.mountCallBack) {54        props.mountCallBack(this)55      }56    },57    render: h => h(App)58  })59}60/**61 * åºç¨æ¯æ¬¡ ååº/å¸è½½ ä¼è°ç¨çæ¹æ³ï¼éå¸¸å¨è¿éæä»¬ä¼å¸è½½å¾®åºç¨çåºç¨å®ä¾62 */63export async function unmount (props) {64  $vm.$destroy()65}66/**67 * å¯éçå½å¨æé©åï¼ä»ä½¿ç¨ loadMicroApp æ¹å¼å è½½å¾®åºç¨æ¶çæ68 */69export async function update (props) {70  console.log('update props', props)...

index.js

Source:index.js

1const { Router } = require('express');2const Database = require('./db');3const mount = require('./mount');4const load = require('./load');5function create(db, callback) {6    const router = Router({ mergeParams: true });7    for (const doc of db.all()) {8        mount(router, doc, callback);9    }10    return router;11}12function watchFile(filename, callback) {13    require('chokidar')14        .watch(filename)15        .on('change', function(filename) {16            callback(null, filename);17        })18        .on('unlink', function() {19            callback(null, null);20        })21        .on('error', err => callback(err));22}23function mockit(filename, watchCallback, mountCallback) {24    let db;25    if (typeof filename === 'string') {26        db = new Database();27    } else {28        mountCallback = watchCallback;29        watchCallback = null;30        if (filename instanceof Database) {31            // db32            db = filename;33        } else if (typeof filename === 'object') {34            db = new Database();35        } else {36            throw new Error('invalid file type');37        }38    }39    const router = Router({ mergeParams: true });40    let subRouter;41    router.use((req, res, next) => {42        if (subRouter) {43            subRouter(req, res, next);44        } else {45            next();46        }47    });48    db.hook(db => {49        subRouter = create(db, mountCallback);50    });51    if (typeof watchCallback === 'function') {52        watchFile(filename, (err, filename) => {53            if (err) {54                watchCallback(err);55            } else {56                try {57                    if (filename) {58                        db.load(load(filename));59                    } else {60                        db.drop();61                    }62                } catch (error) {63                    watchCallback(null, filename != null);64                    return;65                }66                watchCallback(null, filename != null);67            }68        });69    }70    if (typeof filename === 'string') {71        db.load(require('./load')(filename));72    } else if (filename instanceof Database) {73        subRouter = create(filename, mountCallback);74    } else {75        db.load(filename);76    }77    return router;78}79mockit.Database = Database;80mockit.load = load;81mockit.mount = mount;82mockit.default = mockit;...

WithData.js

Source:WithData.js

...56      if (this.gotData) {57        if (mountCallback) {58          const self = this59          setTimeout(() => {60            mountCallback && mountCallback(self)61          }, 1)62        }63        return (64          <Component65            {...props}66            {...this.state}67            dataHandlers={this.dataHandlers}68          />69        )70      } else if (defaultElement) {71        return defaultElement72      }73      return <div style={{ display: "inline" }} className="react-loading" />74    }...

message-list-spec.js

Source: message-list-spec.js

...16      })17    })18  })19  context('MessageList without props', () => {20    beforeEach(mountCallback(MessageList))21    it('shows no messages', () => {22      getItems().should('not.exist')23    })24    it('shows messages', () => {25      getItems().should('not.exist')26      // after mounting we can set props using "Cypress.vue"27      cy.log('setting messages').then(() => {28        Cypress.vue.messages = ['one', 'two']29      })30      getItems().should('have.length', 2)31      cy.then(() => {32        Cypress.vue.messages.push('three')33        getItems().should('have.length', 3)34      })35    })36  })37  context('MessageList with props', () => {38    const template = `39    <div>40      <MessageList :messages="messages"/>41    </div>42  `43    const data = () => ({ messages: ['uno', 'dos'] })44    const components = {45      MessageList,46    }47    beforeEach(mountCallback({ template, data, components }))48    it('shows two items at the start', () => {49      getItems().should('have.length', 2)50    })51  })52  context('MessageList under message-list name', () => {53    const template = `54    <div>55      <message-list :messages="messages"/>56    </div>57  `58    const data = () => ({ messages: ['uno', 'dos'] })59    const components = {60      'message-list': MessageList,61    }62    beforeEach(mountCallback({ template, data, components }))63    it('starts with two items', () => {64      expect(Cypress.vue.messages).to.deep.equal(['uno', 'dos'])65    })66    it('shows two items at the start', () => {67      getItems().should('have.length', 2)68    })69  })...

hello-component-spec.js

Source:hello-component-spec.js

1import Hello from './Hello.vue'2import { mountCallback } from '@cypress/vue'3/* eslint-env mocha */4describe('Hello.vue', () => {5  beforeEach(mountCallback(Hello))6  it('shows hello', () => {7    cy.contains('Hello World!')8  })9})10describe('Several components', () => {11  const template = `12    <div>13      <hello></hello>14      <hello></hello>15      <hello></hello>16    </div>17  `18  const components = {19    hello: Hello,20  }21  beforeEach(mountCallback({ template, components }))22  it('greets the world 3 times', () => {23    cy.get('p').should('have.length', 3)24  })...

Using AI Code Generation

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

Using AI Code Generation

1const { mountCallback } = require('playwright-core/lib/server/browserContext');2const { chromium } = require('playwright-core');3(async () => {4  const browser = await chromium.launch();5  const context = await browser.newContext();6  const page = await context.newPage();7  const callback = () => {8    console.log('Hello from page');9  };10  await mountCallback(page, callback);11  await page.evaluate(() => globalThis.__playwrightCallback());12  await page.evaluate(() => delete globalThis.__playwrightCallback);13  await browser.close();14})();15const { chromium } = require('playwright-core');16describe('Playwright Internal API', () => {17  it('should be able to mount callback', async () => {18    const browser = await chromium.launch();19    const context = await browser.newContext();20    const page = await context.newPage();21    const callback = () => {22      console.log('Hello from page');23    };24    await mountCallback(page, callback);25    await page.evaluate(() => globalThis.__playwrightCallback());26    await page.evaluate(() => delete globalThis.__playwrightCallback);27    await browser.close();28  });29});30import { chromium } from 'playwright-core';31import { mountCallback } from 'playwright-core/lib/server/browserContext';32(async () => {33  const browser = await chromium.launch();34  const context = await browser.newContext();35  const page = await context.newPage();36  const callback = () => {37    console.log('Hello from page');38  };39  await mountCallback(page, callback);40  await page.evaluate(() => globalThis.__playwrightCallback());41  await page.evaluate(() => delete globalThis.__playwrightCallback);42  await browser.close();43})();44import {

Using AI Code Generation

1const playwright = require('playwright');2const { mountCallback } = require('playwright/lib/server/browserContext');3(async () => {4  const browser = await playwright.chromium.launch();5  const context = await browser.newContext();6  const page = await context.newPage();7  const [request] = await Promise.all([8    page.waitForEvent('request'),9  ]);10  console.log(request.url());11  await browser.close();12})();13const playwright = require('playwright');14const { mountCallback } = require('playwright/lib/server/browserContext');15(async () => {16  const browser = await playwright.chromium.launch();17  const context = await browser.newContext();18  const page = await context.newPage();19  const [request] = await Promise.all([20    page.waitForEvent('request'),21  ]);22  console.log(request.url());23  await browser.close();24})();25const playwright = require('playwright');26const { mountCallback } = require('playwright/lib/server/browserContext');27(async () => {28  const browser = await playwright.chromium.launch();29  const context = await browser.newContext();30  const page = await context.newPage();31  const [request] = await Promise.all([32    page.waitForEvent('request'),33  ]);34  console.log(request.url());35  await browser.close();36})();37const playwright = require('playwright');38const { mountCallback } = require('playwright/lib/server/browserContext');39(async () => {40  const browser = await playwright.chromium.launch();41  const context = await browser.newContext();42  const page = await context.newPage();43  const [request] = await Promise.all([44    page.waitForEvent('request'),45  ]);46  console.log(request.url());47  await browser.close();48})();49const playwright = require('playwright');

Using AI Code Generation

1const { mountCallback } = require('playwright/lib/server/browserType');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const context = await browser.newContext();6  await mountCallback(context, 'test', async (arg1, arg2) => {7    console.log(arg1, arg2);8    return 'test';9  });10  const page = await context.newPage();11  const result = await page.evaluate(async () => {12    return await window.playwright.test('hello', 'world');13  });14  console.log(result);15  await browser.close();16})();17const { mountCallback } = require('playwright/lib/server/browserContext');18const { chromium } = require('playwright');19(async () => {20  const browser = await chromium.launch();21  const context = await browser.newContext();22  const page = await context.newPage();23  await mountCallback(page, 'test', async (arg1, arg2) => {24    console.log(arg1, arg2);25    return 'test';26  });27  const result = await page.evaluate(async () => {28    return await window.playwright.test('hello', 'world');29  });30  console.log(result);31  await browser.close();32})();33const { mountCallback } = require('playwright/lib/server/page');34const { chromium } = require('playwright');35(async () => {36  const browser = await chromium.launch();37  const context = await browser.newContext();38  const page = await context.newPage();

Using AI Code Generation

1const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');2const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');3const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');4const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');5const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');6const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');7const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');8const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');9const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');10const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');11const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');12const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');13const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');14const { mountCallback } = require('playwright/lib/server/supplements/recorder/recorderSupplement');15const { mountCallback } = require

Using AI Code Generation

1const { mountCallback } = require('playwright/lib/server/browserContext');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const context = await browser.newContext();6  mountCallback(context, 'customMethod', (arg1, arg2) => {7    console.log('customMethod called with args', arg1, arg2);8    return { result: 'my result' };9  });10  const page = await context.newPage();11  const result = await page.evaluate(async () => {12    return await window.__playwright__customMethod('foo', 'bar');13  });14  console.log('result', result);15  await browser.close();16})();17result { result: 'my result' }18To use the Playwright internal API, import it from the playwright/lib/server/ directory. For example, to use the mountCallback method, import it as follows:19const { mountCallback } = require('playwright/lib/server/browserContext');20const { mountCallback } = require('playwright/lib/server/browserContext');21const { chromium } = require('playwright');22(async () => {23  const browser = await chromium.launch();24  const context = await browser.newContext();25  mountCallback(context, 'customMethod', (arg1, arg2) => {26    console.log('customMethod called with args', arg1, arg2);27    return { result: 'my result

Using AI Code Generation

1const { chromium } = require('playwright');2const context = await chromium.launch().newContext();3const page = await context.newPage();4await context.mountCallback(async (route, request) => {5  if (request.url().endsWith('.png')) {6    await route.fulfill({7      body: Buffer.from('iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhK7jHwAAAABJRU5ErkJggg==', 'base64'),8    });9  } else {10    await route.continue();11  }12});13const { chromium } = require('playwright');14const browser = await chromium.launch();15const context = await browser.newContext();16const page = await context.newPage();17await context.mountCallback(async (route, request) => {18  if (request.url().endsWith('.png')) {19    await route.fulfill({20      body: Buffer.from('iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhK7jHwAAAABJRU5ErkJggg==', 'base64'),21    });22  } else {23    await route.continue();24  }25});26const { chromium } = require('playwright');27const browser = await chromium.launch();28const context = await browser.newContext();29const page = await context.newPage();30await browser.mountCallback(async (route, request) => {31  if (request.url().endsWith('.png')) {32    await route.fulfill({33      body: Buffer.from('iVBORw0KGgoAAAANSUhEUgAAAAEAAAABC

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const context = await browser.newContext();5  context._browserContext._options.recordVideo.dir = '/home/username/Videos';6  const page = await context.newPage();7  await page.screenshot({ path: 'example.png' });8  await browser.close();9})();10const { chromium } = require('playwright');11(async () => {12  const browser = await chromium.launch();13  const context = await browser.newContext();14  context._browserContext._options.recordVideo.dir = '/home/username/Videos';15  const page = await context.newPage();16  await page.screenshot({ path: 'example.png' });17  await browser.close();18})();19const { chromium } = require('playwright');20(async () => {21  const browser = await chromium.launch();22  const context = await browser.newContext();23  context._browserContext._options.recordVideo.dir = '/home/username/Videos';24  const page = await context.newPage();25  await page.screenshot({ path: 'example.png' });26  await browser.close();27})();28const { chromium } = require('playwright');29(async () => {30  const browser = await chromium.launch();31  const context = await browser.newContext();32  context._browserContext._options.recordVideo.dir = '/home/username/Videos';33  const page = await context.newPage();34  await page.screenshot({ path: 'example.png' });35  await browser.close();36})();

StackOverFlow community discussions

Questions

Discussion

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

firefox browser does not start in playwright

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

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

Blogs

Check out the latest blogs from LambdaTest on this topic:

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).

How To Use Appium Inspector For Mobile Apps

Let’s put it short: Appium Desktop = Appium Server + Inspector. When Appium Server runs automation test scripts, Appium Inspector can identify the UI elements of every application under test. The core structure of an Appium Inspector is to ensure that you discover every visible app element when you develop your test scripts. Before you kickstart your journey with Appium Inspector, you need to understand the details of it.

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.

Using ChatGPT for Test Automation

ChatGPT broke all Internet records by going viral in the first week of its launch. A million users in 5 days are unprecedented. A conversational AI that can answer natural language-based questions and create poems, write movie scripts, write social media posts, write descriptive essays, and do tons of amazing things. Our first thought when we got access to the platform was how to use this amazing platform to make the lives of web and mobile app testers easier. And most importantly, how we can use ChatGPT for automated testing.

How To Use CSS Contain Property To Optimize Browsers

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.