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How to use chunkFromParams method in Playwright Internal

Best JavaScript code snippet using playwright-internal

dispatcher.js

...283      (_this$_reporter$onSte2 = (_this$_reporter7 = this._reporter).onStepEnd) === null || _this$_reporter$onSte2 === void 0 ? void 0 : _this$_reporter$onSte2.call(_this$_reporter7, test, result, step);284    });285    worker.on('stdOut', params => {286      var _this$_reporter$onStd2, _this$_reporter8;287      const chunk = chunkFromParams(params);288      const pair = params.testId ? this._testById.get(params.testId) : undefined;289      if (pair) pair.result.stdout.push(chunk);290      (_this$_reporter$onStd2 = (_this$_reporter8 = this._reporter).onStdOut) === null || _this$_reporter$onStd2 === void 0 ? void 0 : _this$_reporter$onStd2.call(_this$_reporter8, chunk, pair === null || pair === void 0 ? void 0 : pair.test, pair === null || pair === void 0 ? void 0 : pair.result);291    });292    worker.on('stdErr', params => {293      var _this$_reporter$onStd3, _this$_reporter9;294      const chunk = chunkFromParams(params);295      const pair = params.testId ? this._testById.get(params.testId) : undefined;296      if (pair) pair.result.stderr.push(chunk);297      (_this$_reporter$onStd3 = (_this$_reporter9 = this._reporter).onStdErr) === null || _this$_reporter$onStd3 === void 0 ? void 0 : _this$_reporter$onStd3.call(_this$_reporter9, chunk, pair === null || pair === void 0 ? void 0 : pair.test, pair === null || pair === void 0 ? void 0 : pair.result);298    });299    worker.on('teardownError', ({300      error301    }) => {302      var _this$_reporter$onErr2, _this$_reporter10;303      this._hasWorkerErrors = true;304      (_this$_reporter$onErr2 = (_this$_reporter10 = this._reporter).onError) === null || _this$_reporter$onErr2 === void 0 ? void 0 : _this$_reporter$onErr2.call(_this$_reporter10, error);305    });306    worker.on('exit', () => {307      this._workers.delete(worker);308      this._notifyWorkerClaimer();309      if (this._stopCallback && !this._workers.size) this._stopCallback();310    });311    this._workers.add(worker);312    return worker.init(testGroup).then(() => worker);313  }314  async stop() {315    this._isStopped = true;316    if (this._workers.size) {317      const result = new Promise(f => this._stopCallback = f);318      for (const worker of this._workers) worker.stop();319      await result;320    }321    while (this._workerClaimers.length) this._workerClaimers.shift()();322  }323  _hasReachedMaxFailures() {324    const maxFailures = this._loader.fullConfig().maxFailures;325    return maxFailures > 0 && this._failureCount >= maxFailures;326  }327  _reportTestEnd(test, result) {328    var _this$_reporter$onTes4, _this$_reporter11;329    if (result.status !== 'skipped' && result.status !== test.expectedStatus) ++this._failureCount;330    (_this$_reporter$onTes4 = (_this$_reporter11 = this._reporter).onTestEnd) === null || _this$_reporter$onTes4 === void 0 ? void 0 : _this$_reporter$onTes4.call(_this$_reporter11, test, result);331    const maxFailures = this._loader.fullConfig().maxFailures;332    if (maxFailures && this._failureCount === maxFailures) this.stop().catch(e => {});333  }334  hasWorkerErrors() {335    return this._hasWorkerErrors;336  }337}338exports.Dispatcher = Dispatcher;339let lastWorkerIndex = 0;340class Worker extends _events.EventEmitter {341  constructor(runner) {342    super();343    this.process = void 0;344    this.runner = void 0;345    this.hash = '';346    this.index = void 0;347    this.didSendStop = false;348    this.runner = runner;349    this.index = lastWorkerIndex++;350    this.process = _child_process.default.fork(_path.default.join(__dirname, 'worker.js'), {351      detached: false,352      env: {353        FORCE_COLOR: process.stdout.isTTY ? '1' : '0',354        DEBUG_COLORS: process.stdout.isTTY ? '1' : '0',355        TEST_WORKER_INDEX: String(this.index),356        ...process.env357      },358      // Can't pipe since piping slows down termination for some reason.359      stdio: ['ignore', 'ignore', process.env.PW_RUNNER_DEBUG ? 'inherit' : 'ignore', 'ipc']360    });361    this.process.on('exit', () => this.emit('exit'));362    this.process.on('error', e => {}); // do not yell at a send to dead process.363    this.process.on('message', message => {364      const {365        method,366        params367      } = message;368      this.emit(method, params);369    });370  }371  async init(testGroup) {372    this.hash = testGroup.workerHash;373    const params = {374      workerIndex: this.index,375      repeatEachIndex: testGroup.repeatEachIndex,376      projectIndex: testGroup.projectIndex,377      loader: this.runner._loader.serialize()378    };379    this.process.send({380      method: 'init',381      params382    });383    await new Promise(f => this.process.once('message', f)); // Ready ack384  }385  run(testGroup) {386    const runPayload = {387      file: testGroup.requireFile,388      entries: testGroup.tests.map(test => {389        return {390          testId: test._id,391          retry: test.results.length - 1392        };393      })394    };395    this.process.send({396      method: 'run',397      params: runPayload398    });399  }400  stop() {401    if (!this.didSendStop) this.process.send({402      method: 'stop'403    });404    this.didSendStop = true;405  }406}407function chunkFromParams(params) {408  if (typeof params.text === 'string') return params.text;409  return Buffer.from(params.buffer, 'base64');...

Using AI Code Generation

1const { chunkFromParams } = require('playwright/lib/utils/stackTrace');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const page = await browser.newPage();6  const lines = await page.evaluate(() => {7    const chunk = chunkFromParams({ foo: 'bar' });8    return chunk.split('\n');9  });10  console.log(lines);11  await browser.close();12})();13We welcome contributions! Please read our [contributing guidelines](

Using AI Code Generation

1const { chunkFromParams } = require('playwright/lib/server/chromium/crNetworkManager');2const { makeWaitForNextTask } = require('playwright/lib/utils/utils');3const { assert } = require('console');4(async () => {5  const waitForNextTask = makeWaitForNextTask();6  const chunk = chunkFromParams('1234', 'hello', 0, 5);7  assert.strictEqual(chunk.toString(), 'hello');8  await waitForNextTask();9})();10And then in your test code, import the `chunkFromParams` method from this library11const { chunkFromParams } = require('playwright-chunk-from-params');

Using AI Code Generation

1const { chunkFromParams } = require('@playwright/test/lib/utils/stackTrace');2const { test } = require('@playwright/test');3test('test', async () => {4  const chunk = chunkFromParams({ title: 'test' });5  console.log(chunk);6});7{8}

Using AI Code Generation

1const { chunkFromParams } = require('playwright/lib/webkit/wkPage');2const { getTestState } = require('playwright/lib/test');3const { getBrowserContext } = require('playwright/lib/server/browserContext');4const { getBrowser } = require('playwright/lib/server/browser');5const { getWebKit } = require('playwright/lib/server/webkit');6const { chunkFromParams } = require('playwright/lib/webkit/wkPage');7const { getTestState } = require('playwright/lib/test');8const { getBrowserContext } = require('playwright/lib/server/browserContext');9const { getBrowser } = require('playwright/lib/server/browser');10const { getWebKit } = require('playwright/lib/server/webkit');11const { chunkFromParams } = require('playwright/lib/webkit/wkPage');12const { getTestState } = require('playwright/lib/test');13const { getBrowserContext } = require('playwright/lib/server/browserContext');14const { getBrowser } = require('playwright/lib/server/browser');15const { getWebKit } = require('playwright/lib/server/webkit');16const { chunkFromParams } = require('playwright/lib/webkit/wkPage');17const { getTestState } = require('playwright/lib/test');18const { getBrowserContext } = require('playwright/lib/server/browserContext');19const { getBrowser } = require('playwright/lib/server/browser');20const { getWebKit } = require('playwright/lib/server/webkit');21const { chunkFromParams } = require('playwright/lib/webkit/wkPage');22const { getTestState } = require('playwright/lib/test');23const { getBrowserContext } = require('playwright/lib/server/browserContext');24const { getBrowser } = require('playwright/lib/server/browser');25const { getWebKit } = require('playwright/lib/server/webkit');26const { chunkFromParams } = require('playwright/lib/webkit/wkPage');27const { getTestState } = require('playwright/lib/test');28const { getBrowserContext } = require('play

Using AI Code Generation

1const { chunkFromParams } = require('playwright/lib/server/chromium/crBrowser');2const chunk = chunkFromParams('test.js', 123, 456);3console.log(chunk);4{5}6const { chunkFromParams } = require('playwright/lib/server/chromium/crBrowser');7const chunk = chunkFromParams('test.js', 123, 456);8console.log(chunk);9{10}11const { chunkFromParams } = require('playwright/lib/server/chromium/crBrowser');12const chunk = chunkFromParams('test.js', 123, 456);13console.log(chunk);14{15}16const { chunkFromParams } = require('playwright/lib/server/chromium/crBrowser');17const chunk = chunkFromParams('test.js', 123, 456);18console.log(chunk);

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const page = await browser.newPage();5  const chunk = await page.context().evaluateHandle((injected, options) => {6    return window['playwright'].chunkFromParams(injected, options);7  }, 'console.log("hello")', { isFunction: true });8  await page.evaluate(chunk => chunk(), chunk);9  await browser.close();10})();11#### playwrightInternal.chunkFromParams(injected, options)12[Apache 2.0](./LICENSE)

StackOverFlow community discussions

Questions

Discussion

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

firefox browser does not start in playwright

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

Running Playwright in Azure Function

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

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

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