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How to use mountLazyComponent method in Playwright Internal

Best JavaScript code snippet using playwright-internal

0__index.js

...144            return mountIndeterminateComponent(current$$1, workInProgress, workInProgress.type, renderExpirationTime);145        }146        case LazyComponent: {147            var elementType = workInProgress.elementType;148            return mountLazyComponent(current$$1, workInProgress, elementType, updateExpirationTime, renderExpirationTime);149        }150        case FunctionComponent: {151            var _Component = workInProgress.type;152            var unresolvedProps = workInProgress.pendingProps;153            var resolvedProps = workInProgress.elementType === _Component ? unresolvedProps : resolveDefaultProps(_Component, unresolvedProps);154            return updateFunctionComponent(current$$1, workInProgress, _Component, resolvedProps, renderExpirationTime);155        }156        case ClassComponent: {157            var _Component2 = workInProgress.type;158            var _unresolvedProps = workInProgress.pendingProps;159            var _resolvedProps = workInProgress.elementType === _Component2 ? _unresolvedProps : resolveDefaultProps(_Component2, _unresolvedProps);160            return updateClassComponent(current$$1, workInProgress, _Component2, _resolvedProps, renderExpirationTime);161        }162        case HostRoot:...

beginWork.js

Source: beginWork.js

...195      );196    }197    case LazyComponent: {198      const elementType = workInProgress.elementType;199      return mountLazyComponent(200        current,201        workInProgress,202        elementType,203        updateExpirationTime,204        renderExpirationTime,205      );206    }207    case FunctionComponent: {208      const Component = workInProgress.type;209      const unresolvedProps = workInProgress.pendingProps;210      const resolvedProps =211        workInProgress.elementType === Component212          ? unresolvedProps213          : resolveDefaultProps(Component, unresolvedProps);...

ReactFiberBeginWork.js

Source: ReactFiberBeginWork.js

...136      );137    }138    case LazyComponent: {139      const elementType = workInProgress.elementType;140      return mountLazyComponent(141        current,142        workInProgress,143        elementType,144        updateExpirationTime,145        renderExpirationTime,146      );147    }148    case FunctionComponent: {149      const Component = workInProgress.type;150      const unresolvedProps = workInProgress.pendingProps;151      const resolvedProps =152        workInProgress.elementType === Component ?153        unresolvedProps :154        resolveDefaultProps(Component, unresolvedProps);...

visitor.js

Source: visitor.js

...124    }125    case REACT_LAZY_TYPE: {126      const lazyElement = ((element: any): LazyElement)127      const type = lazyElement.type128      const child = mountLazyComponent(type, lazyElement.props, queue)129      return getChildrenArray(child)130    }131    case REACT_MEMO_TYPE: {132      const memoElement = ((element: any): MemoElement)133      const { type } = memoElement.type134      const child = createElement((type: any), memoElement.props)135      return getChildrenArray(child)136    }137    case REACT_FORWARD_REF_TYPE: {138      const refElement = ((element: any): ForwardRefElement)139      const { render: type, defaultProps } = refElement.type140      const props = computeProps(refElement.props, defaultProps)141      const child = createElement((type: any), props)142      return getChildrenArray(child)...

index.next.js

Source: index.next.js

...15    mount(el, parentScope) {16      this.el = el17      this.isMounted = true18      const mount = () => {19        this.mountLazyComponent(parentScope)20        this.el.dispatchEvent(new Event('load'))21      }22      if (cachedComponent) {23        mount()24      } else {25        if (hasLoader) this.createManagedComponent(Loader, parentScope)26        load().then(data => {27          cache.set(LazyComponent, data.default || data)28          mount()29        })30      }31    },32    createManagedComponent(Child, parentScope) {33      this.component = component(Child)(this.el, props, {34        attributes, slots, parentScope35      })36    },37    mountLazyComponent(parentScope) {38      // if this component was unmounted just return here39      if (!this.isMounted) return40      // unmount the loader if it was previously created41      if (this.component) {42        // unmount the bindings (keeping the root node)43        this.component.unmount(true)44        // clean the DOM45        if (this.el.children.length) cleanNode(this.el)46      }47      // replace the old component instance with the new lazy loaded component48      this.createManagedComponent(cache.get(LazyComponent), parentScope)49    },50    update(parentScope) {51      if (this.isMounted && this.component) this.component.update({}, parentScope)...

bfsPromise.js

Source: bfsPromise.js

...50  }51}52function originBeginWork(current, workInProgress) {53  const elementType = {}54  return mountLazyComponent(current, workInProgress,elementType)55}56function mountLazyComponent(current, workInProgress, elementType) {57  const props = workInProgress.pendingProps;58  const lazyComponent = elementType;59  const payload = lazyComponent._payload;60  const init = lazyComponent._init;61  let Component = init(payload);62}63function completeUnitOfWork() {64}65let link = {66  val: 1,67  alter: null,68  next: {69    val: 2,70    alter: null,...

index.js

Source: index.js

1// @flow2/** Every type of component here can suspend itself.3    This means it pushes a `Frame` to the queue.4    Components are first mounted in visitor.js,5    and if they have suspended after their promise6    resolves `update` is called instead for them,7    which preserves their previous mounted state8    and rerenders the component. */9export {10  mount as mountLazyComponent,11  update as updateLazyComponent12} from './lazyComponent'13export {14  mount as mountFunctionComponent,15  update as updateFunctionComponent16} from './functionComponent'17export {18  mount as mountClassComponent,19  update as updateClassComponent...

Using AI Code Generation

1const path = require('path');2const {chromium} = require('playwright');3const {mountLazyComponent} = require('playwright/internal');4(async () => {5  const browser = await chromium.launch();6  const page = await browser.newPage();7  const {element} = await mountLazyComponent(page, {8    path: path.join(__dirname, 'component.js'),9  });10  console.log(await element.evaluate((e) => e.textContent));11  await browser.close();12})();13const {mount} = require('playwright/internal');14module.exports = mount('my-component', {15  attributes: {16  },17  slots: {18      {19      },20  },21});22const path = require('path');23const {chromium} = require('playwright');24const {mountLazyComponent} = require('playwright/internal');25(async () => {26  const browser = await chromium.launch();27  const page = await browser.newPage();28  const {element} = await mountLazyComponent(page, {29    path: path.join(__dirname, 'component.js'),30  });31  console.log(await element.evaluate((e) => e.textContent));32  await browser.close();33})();34const {mount} = require('playwright/internal');35module.exports = mount('my-component', {36  attributes: {37  },38  slots: {39      {40      },41  },42});43const path = require('path');44const {chromium} = require('playwright');45const {mountLazyComponent} = require('playwright/internal');46(async () => {

Using AI Code Generation

1const { mountLazyComponent } = require('playwright-core/lib/server/supplements/recorder/recorderSupplement');2const { Page } = require('playwright-core/lib/server/page');3const { Frame } = require('playwright-core/lib/server/frames');4const { ElementHandle } = require('playwright-core/lib/server/dom');5const { JSHandle } = require('playwright-core/lib/server/javascript');6const { serializeResult } = require('playwright-core/lib/server/serializers');7const { chromium } = require('playwright-core');8(async () => {9  const browser = await chromium.launch();10  const page = await browser.newPage();11  await page.click('text="I agree"');12  await page.click('input[name="q"]');13  await page.fill('input[name="q"]', 'playwright');14  await page.click('text="Google Search"');15  await page.click('text="Playwright: Node.js library to automate ... - Google Search"');16  await page.click('text="Get started"');17  await page.click('text="Install"');18  const element = await page.$('text="NPM"');19  const result = await mountLazyComponent(page, element, 'test', 'test');20  console.log(result);21  await browser.close();22})();23import { chromium } from 'playwright-core';24import { mountLazyComponent } from 'playwright-core/lib/server/supplements/recorder/recorderSupplement';25import { Page } from 'playwright-core/lib/server/page';26import { Frame } from 'playwright-core/lib/server/frames';27import { ElementHandle } from 'playwright-core/lib/server/dom';28import { JSHandle } from 'playwright-core/lib/server/javascript';29import { serializeResult } from 'playwright-core/lib/server/serializers';30(async () => {31  const browser = await chromium.launch();32  const page = await browser.newPage();33  await page.click('text="I agree"');34  await page.click('input[name="q"]');35  await page.fill('input[name="q"]', 'playwright');36  await page.click('text="Google Search"');37  await page.click('text="Playwright: Node.js library to automate ... - Google Search

Using AI Code Generation

1const { mountLazyComponent } = require('playwright-core/lib/server/frames');2const { Frame } = require('playwright-core/lib/server/frames');3const { Page } = require('playwright-core/lib/server/page');4const frame = new Frame(page, 'frameName', parentFrame, frameId);5const componentHandle = await mountLazyComponent(frame, component, props, state);6const { unmountLazyComponent } = require('playwright-core/lib/server/frames');7const { Frame } = require('playwright-core/lib/server/frames');8const { Page } = require('playwright-core/lib/server/page');9const frame = new Frame(page, 'frameName', parentFrame, frameId);10await unmountLazyComponent(frame, componentHandle);11const { waitForFunction } = require('playwright-core/lib/server/injected/injectedScript');12const { Frame } = require('playwright-core/lib/server/frames');13const { Page } = require('playwright-core/lib/server/page');14const frame = new Frame(page, 'frameName', parentFrame, frameId);15await waitForFunction(frame, 'return window.innerWidth < 100', true, null, 1000);16const { waitForSelector } = require('playwright-core/lib/server/injected/injectedScript');17const { Frame } = require('playwright-core/lib/server/frames');18const { Page } = require('playwright-core/lib/server/page');19const frame = new Frame(page, 'frameName', parentFrame, frameId);20await waitForSelector(frame, '.box', 'visible', null, 1000);

Using AI Code Generation

1const { mountLazyComponent } = require('playwright/lib/server/supplements/recorder/recorderSupplement.js');2const { test } = require('@playwright/test');3test('test', async ({ page }) => {4  await mountLazyComponent(page, 'recorder');5});6{7  "compilerOptions": {8  }9}

Using AI Code Generation

1const { mountLazyComponent } = require('@playwright/test');2const { MyComponent } = require('./component');3mountLazyComponent(MyComponent);4const MyComponent = () => {5  return {6    render: () => {7      return 'Hello World';8    },9  };10};11module.exports = { MyComponent };

Using AI Code Generation

1const { mountLazyComponent } = require('@playwright/test');2const { expect } = require('@playwright/test');3const { test, expect } = require('@playwright/test');4test('test', async ({ page }) => {5  await mountLazyComponent(page, { name: 'my-component' });6  await page.waitForSelector('my-component');7  await expect(page).toHaveSelector('my-component');8  await mountLazyComponent(page, { name: 'my-component', mount: false });9  await expect(page).not.toHaveSelector('my-component');10});11const { test, expect } = require('@playwright/test');12test('test', async ({ page }) => {13  await page.waitForSelector('my-component');14  await expect(page).toHaveSelector('my-component');15  const element = await page.$('my-component');16  await expect(element).toHaveText('Hello, World! I\'m ');17});

StackOverFlow community discussions

Questions

Discussion

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

firefox browser does not start in playwright

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

firefox browser does not start in playwright

How to run a list of test suites in a single file concurrently in jest?

Running Playwright in Azure Function

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

This question is quite close to a "need more focus" question. But let's try to give it some focus:

Does Playwright has access to the cPicker object on the page? Does it has access to the window object?

Yes, you can access both cPicker and the window object inside an evaluate call.

Should I trigger the events from the HTML file itself, and in the callbacks, print in the DOM the result, in some dummy-element, and then infer from that dummy element text that the callbacks fired?

Exactly, or you can assign values to a javascript variable:

const cPicker = new ColorPicker({
  onClickOutside(e){
  },
  onInput(color){
    window['color'] = color;
  },
  onChange(color){
    window['result'] = color;
  }
})

And then

it('Should call all callbacks with correct arguments', async() => {
    await page.goto(`http://localhost:5000/tests/visual/basic.html`, {waitUntil:'load'})

    // Wait until the next frame
    await page.evaluate(() => new Promise(requestAnimationFrame))

    // Act
   
    // Assert
    const result = await page.evaluate(() => window['color']);
    // Check the value
})

https://stackoverflow.com/questions/65477895/jest-playwright-test-callbacks-of-event-based-dom-library

I found the error. It was because of some missing libraries need. I discovered this when I downgraded playwright to version 1.9 and ran the the code then this was the error msg:

(node:12876) UnhandledPromiseRejectionWarning: browserType.launch: Host system is missing dependencies!

Some of the Universal C Runtime files cannot be found on the system. You can fix
that by installing Microsoft Visual C++ Redistributable for Visual Studio from:
https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads

Full list of missing libraries:
    vcruntime140.dll
    msvcp140.dll
Error
    at Object.captureStackTrace (D:\Projects\snkrs-play\node_modules\playwright\lib\utils\stackTrace.js:48:19)
    at Connection.sendMessageToServer (D:\Projects\snkrs-play\node_modules\playwright\lib\client\connection.js:69:48)
    at Proxy.<anonymous> (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:64:61)
    at D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:64:67
    at BrowserType._wrapApiCall (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:77:34)
    at BrowserType.launch (D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:55:21)
    at D:\Projects\snkrs-play\index.js:4:35
    at Object.<anonymous> (D:\Projects\snkrs-play\index.js:7:3)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:12876) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:12876) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

A list of missing libraries was provided. After successful installments, firefox ran fine. I upgraded again to version 1.10 and firefox still works.

https://stackoverflow.com/questions/66984974/firefox-browser-does-not-start-in-playwright

Assuming you are not running test with the --runinband flag, the simple answer is yes but it depends ????

There is a pretty comprehensive GitHub issue jest#6957 that explains certain cases of when tests are run concurrently or in parallel. But it seems to depend on a lot of edge cases where jest tries its best to determine the fastest way to run the tests given the circumstances.

To my knowledge there is no way to force jest to run in parallel.

Aside

Have you considered using playwright instead of puppeteer with jest? Playwright has their own internally built testing library called @playwright/test that is used in place of jest with a similar API. This library allows for explicitly defining test groups in a single file to run in parallel (i.e. test.describe.parallel) or serially (i.e. test.describe.serial). Or even to run all tests in parallel via a config option.

// parallel
test.describe.parallel('group', () => {
  test('runs in parallel 1', async ({ page }) => {});
  test('runs in parallel 2', async ({ page }) => {});
});

// serial
test.describe.serial('group', () => {
  test('runs first', async ({ page }) => {});
  test('runs second', async ({ page }) => {});
});

https://stackoverflow.com/questions/73497773/how-to-run-a-list-of-test-suites-in-a-single-file-concurrently-in-jest

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