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How to use memoizeStringOnly method in Playwright Internal

Best JavaScript code snippet using playwright-internal

module$CSSPropertyOperations.js

1goog.provide("module$CSSPropertyOperations");2var module$CSSPropertyOperations = {};3goog.require("module$memoizeStringOnly");4goog.require("module$hyphenate");5goog.require("module$escapeTextForBrowser");6goog.require("module$dangerousStyleValue");7goog.require("module$CSSProperty");8var CSSProperty$$module$CSSPropertyOperations = module$CSSProperty;9var dangerousStyleValue$$module$CSSPropertyOperations = module$dangerousStyleValue;10var escapeTextForBrowser$$module$CSSPropertyOperations = module$escapeTextForBrowser;11var hyphenate$$module$CSSPropertyOperations = module$hyphenate;12var memoizeStringOnly$$module$CSSPropertyOperations = module$memoizeStringOnly;13var processStyleName$$module$CSSPropertyOperations = memoizeStringOnly$$module$CSSPropertyOperations(function(styleName) {14  return escapeTextForBrowser$$module$CSSPropertyOperations(hyphenate$$module$CSSPropertyOperations(styleName))15});16var CSSPropertyOperations$$module$CSSPropertyOperations = {createMarkupForStyles:function(styles) {17  var serialized = "";18  for(var styleName in styles) {19    if(!styles.hasOwnProperty(styleName)) {20      continue21    }22    var styleValue = styles[styleName];23    if(styleValue != null) {24      serialized += processStyleName$$module$CSSPropertyOperations(styleName) + ":";25      serialized += dangerousStyleValue$$module$CSSPropertyOperations(styleName, styleValue) + ";"26    }27  }28  return serialized || null29}, setValueForStyles:function(node, styles) {30  var style = node.style;31  for(var styleName in styles) {32    if(!styles.hasOwnProperty(styleName)) {33      continue34    }35    var styleValue = dangerousStyleValue$$module$CSSPropertyOperations(styleName, styles[styleName]);36    if(styleValue) {37      style[styleName] = styleValue38    }else {39      var expansion = CSSProperty$$module$CSSPropertyOperations.shorthandPropertyExpansions[styleName];40      if(expansion) {41        for(var individualStyleName in expansion) {42          style[individualStyleName] = ""43        }44      }else {45        style[styleName] = ""46      }47    }48  }49}};50module$CSSPropertyOperations.module$exports = CSSPropertyOperations$$module$CSSPropertyOperations;51if(module$CSSPropertyOperations.module$exports) {52  module$CSSPropertyOperations = module$CSSPropertyOperations.module$exports53}...

memoizeStringOnly.js

Source: memoizeStringOnly.js

...15 *16 * @param {function} callback17 * @return {function}18 */19function memoizeStringOnly(callback) {20  var cache = {};21  return function(string) {22    if (!cache.hasOwnProperty(string)) {23      cache[string] = callback.call(this, string);24    }25    return cache[string];26  };27}...

memoizeStringOnly-test.js

Source: memoizeStringOnly-test.js

...18  it('should be transparent to callers', function() {19    var callback = function(string) {20      return string;21    };22    var memoized = memoizeStringOnly(callback);23    expect(memoized('foo'), callback('foo'));24  });...

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright/lib/utils/memoize');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const context = await browser.newContext();6  const page = await context.newPage();7  const memoized = memoizeStringOnly((arg) => arg);8  await browser.close();9})();10I am trying to use the latest version of playwright in my project, but I am getting an error when I try to run my tests. I am using the latest version of playwright (1.6.2) and my test file looks like this:11const { chromium } = require('playwright');12(async () => {13  const browser = await chromium.launch();14  const context = await browser.newContext();15  const page = await context.newPage();16  await page.screenshot({ path: `example.png` });17  await browser.close();18})();19    at processTicksAndRejections (internal/process/task_queues.js:97:5)

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright/lib/utils/memoize');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const page = await browser.newPage();6  await page.screenshot({ path: `example.png` });7  await browser.close();8})();

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright/lib/utils/memoize');2const { chromium } = require('playwright');3const browser = await chromium.launch();4const context = await browser.newContext();5const page = await context.newPage();6const memoized = memoizeStringOnly(async () => {7  const browser = await chromium.launch();8  const context = await browser.newContext();9  const page = await context.newPage();10  await page.screenshot({ path: 'example.png' });11  await browser.close();12});13await memoized();14const memoized = memoizeStringOnly(async () => {15  const browser = await chromium.launch();16  const context = await browser.newContext();17  const page = await context.newPage();18  await page.screenshot({ path: 'example.png' });19  await browser.close();20});21await memoized();22await memoized();23await memoized();24await memoized();25await memoized();26await memoized();27const memoized = memoizeStringOnly(async () => {28  const browser = await chromium.launch();29  const context = await browser.newContext();30  const page = await context.newPage();31  await page.screenshot({ path: 'example.png' });32  await browser.close();33});34await memoized();35await memoized();36await memoized();37await memoized();38await memoized();39await memoized();40await memoized();41const memoized = memoizeStringOnly(async () => {42  const browser = await chromium.launch();43  const context = await browser.newContext();44  const page = await context.newPage();45  await page.screenshot({ path: 'example.png' });46  await browser.close();47});48await memoized();49await memoized();50await memoized();51await memoized();52await memoized();53await memoized();54await memoized();55await memoized();

Using AI Code Generation

1const { memoizeStringOnly } = require('@playwright/test/lib/utils/memoize');2const { test } = require('@playwright/test');3test('test', async ({ page }) => {4  const title1 = await page.title();5  console.log('memoized title 1', memoizeStringOnly(() => page.title()));6  const title2 = await page.title();7  console.log('memoized title 2', memoizeStringOnly(() => page.title()));8});9memoized title 1 Promise { <pending> }10memoized title 2 Promise { <pending> }11const { test, expect } = require('@playwright/test');12test('test', async ({ page }) => {13  await page.route('**/todos', (route) => {14    route.fulfill({15      body: JSON.stringify([{ id: 1, title: 'Hello World', completed: false }]),16    });17  });18  await page.click('text=Clear completed');19  const list = await page.$$('data-test=todo-list li');20  expect(list).toHaveLength(1);21});22const { test, expect } = require('@playwright/test');23test('test', async ({ page }) => {24  await page.exposeBinding('copyToClipboard', async (source, text) => {25    await page.evaluate(() => navigator.clipboard.writeText(text));26  });27  await page.click('text=Clear completed');28  await page.click('text=Active');

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright/lib/utils/memoize');2const fs = require('fs');3const path = require('path');4const os = require('os');5const { chromium } = require('playwright');6const { devices } = require('playwright');7const iPhone = devices['iPhone 11 Pro'];8const iPhoneUserAgent = iPhone.userAgent;9const browser = await chromium.launch();10const context = await browser.newContext({11});12const page = await context.newPage();13const { deviceScaleFactor, isMobile, hasTouch } = page.viewportSize();14const deviceName = 'iPhone 11 Pro';15const screenshot = await page.screenshot({16  path: path.join(os.tmpdir(), `${deviceName}-${deviceScaleFactor}x.png`),17});18const memoizeStringOnly = memoizeStringOnly((x) => x);19const memoized = memoizeStringOnly(() => 42);20console.log(memoized());21await browser.close();22const { memoizeStringOnly } = require('playwright/lib/utils/memoize');23const fs = require('fs');24const path = require('path');25const os = require('os');26const { chromium } = require('playwright');27const { devices } = require('playwright');28const iPhone = devices['iPhone 11 Pro'];29const iPhoneUserAgent = iPhone.userAgent;30const browser = await chromium.launch();31const context = await browser.newContext({32});33const page = await context.newPage();34const { deviceScaleFactor, isMobile, hasTouch } = page.viewportSize();35const deviceName = 'iPhone 11 Pro';36const screenshot = await page.screenshot({37  path: path.join(os.tmpdir(), `${deviceName}-${deviceScaleFactor}x.png`),38});39const memoizeStringOnly = memoizeStringOnly((x) => x);40const memoized = memoizeStringOnly(() => 42);41console.log(memoized());42await browser.close();

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright/lib/server/supplements/recorder/recorderSupplement');2const memoized = memoizeStringOnly((arg) => arg);3console.log(memoized('foo'));4console.log(memoized('foo'));5console.log(memoized('bar'));6console.log(memoized('foo'));7console.log(memoized('bar'));

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright/lib/utils/memoize');2const { chromium } = require('playwright');3const { test } = require('@playwright/test');4test('memoizeStringOnly', async ({ page }) => {5  const browser = await chromium.launch();6  const context = await browser.newContext();7  const page1 = await context.newPage();8  const page2 = await context.newPage();9  const page3 = await context.newPage();10  const page4 = await context.newPage();11  const page5 = await context.newPage();12  const page6 = await context.newPage();13  const page7 = await context.newPage();14  const page8 = await context.newPage();15  const page9 = await context.newPage();16  const page10 = await context.newPage();17  const page11 = await context.newPage();18  const page12 = await context.newPage();19  const page13 = await context.newPage();20  const page14 = await context.newPage();21  const page15 = await context.newPage();22  const page16 = await context.newPage();23  const page17 = await context.newPage();24  const page18 = await context.newPage();25  const page19 = await context.newPage();26  const page20 = await context.newPage();27  const page21 = await context.newPage();28  const page22 = await context.newPage();29  const page23 = await context.newPage();30  const page24 = await context.newPage();31  const page25 = await context.newPage();32  const page26 = await context.newPage();33  const page27 = await context.newPage();34  const page28 = await context.newPage();35  const page29 = await context.newPage();36  const page30 = await context.newPage();37  const page31 = await context.newPage();38  const page32 = await context.newPage();39  const page33 = await context.newPage();40  const page34 = await context.newPage();41  const page35 = await context.newPage();42  const page36 = await context.newPage();43  const page37 = await context.newPage();44  const page38 = await context.newPage();45  const page39 = await context.newPage();46  const page40 = await context.newPage();47  const page41 = await context.newPage();48  const page42 = await context.newPage();

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const page = await browser.newPage();5  await page.screenshot({ path: `example.png` });6  await browser.close();7})();8const { chromium } = require('playwright');9(async () => {10  const browser = await chromium.launch();11  const page = await browser.newPage();12  await page.screenshot({ path: `example.png` });13  await browser.close();14})();

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright/lib/utils/memoize');2const { test, expect } = require('@playwright/test');3test('memoize', async ({ page }) => {4  const memoized = memoizeStringOnly((arg) => arg);5  expect(memoized('foo')).toBe('foo');6  expect(memoized('foo')).toBe('foo');7  expect(memoized('bar')).toBe('bar');8});

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright-core/lib/utils/memoize');2const { getVideoSize } = require('playwright-core/lib/server/video/recorder');3const { getVideoSize } = require('playwright-core/lib/server/video/recorder');4const memoized = memoizeStringOnly((sizeString) => {5  const result = getVideoSize(sizeString);6  console.log(result);7});8memoized('500x500');9memoized('500x500');10{ width: 500, height: 500 }11const memoized = memoizeStringOnly((arg) => {12  return result;13});14[Apache 2.0](../../LICENSE)15(async () => {16  const browser = await chromium.launch();17  const page = await browser.newPage();18  await page.screenshot({ path: `example.png` });19  await browser.close();20})();

Using AI Code Generation

1const { memoizeStringOnly } = require('playwright/lib/utils/memoize');2const { test, expect } = require('@playwright/test');3test('memoize', async ({ page }) => {4  const memoized = memoizeStringOnly((arg) => arg);5  expect(memoized('foo')).toBe('foo');6  expect(memoized('foo')).toBe('foo');7  expect(memoized('bar')).toBe('bar');8});

StackOverFlow community discussions

Questions

Discussion

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

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

Running Playwright in Azure Function

firefox browser does not start in playwright

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

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

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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