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How to use processSlotOutlet method in Playwright Internal

Best JavaScript code snippet using playwright-internal

html-parser.js

Source:html-parser.js

...139    if (!inVPre) {140      processKey(el);141      processRef(el);142      processSlotContent(el);143      processSlotOutlet(el);144      processComponent(el);145      transforms.forEach(transform=>{146        el = transform(el, options) || el;147      });148      processAttrs(el);149      processIfConditions(el);150      processScopedSlot(el, currentParent);151    }152    if (el.pre) {153      inVPre = false;154    }155    156    if (el.tag === 'pre') {157      inPre = false;...

flat1.js

Source:flat1.js

1/* @flow */2import he from 'he'3import { parseHTML } from './html-parser'4import { parseText } from './text-parser'5import { parseFilters } from './filter-parser'6import { genAssignmentCode } from '../directives/model'7import { extend, cached, no, camelize, hyphenate } from 'shared/util'8import { isIE, isEdge, isServerRendering } from 'core/util/env'9import {10  addProp,11  addAttr,12  baseWarn,13  addHandler,14  addDirective,15  getBindingAttr,16  getAndRemoveAttr,17  getRawBindingAttr,18  pluckModuleFunction,19  getAndRemoveAttrByRegex20} from '../helpers'21export const onRE = /^@|^v-on:/22export const dirRE = process.env.VBIND_PROP_SHORTHAND23  ? /^v-|^@|^:|^\.|^#/24  : /^v-|^@|^:|^#/25export const forAliasRE = /([\s\S]*?)\s+(?:in|of)\s+([\s\S]*)/26export const forIteratorRE = /,([^,\}\]]*)(?:,([^,\}\]]*))?$/27const stripParensRE = /^\(|\)$/g28const dynamicArgRE = /^\[.*\]$/29const argRE = /:(.*)$/30export const bindRE = /^:|^\.|^v-bind:/31const propBindRE = /^\./32const modifierRE = /\.[^.\]]+(?=[^\]]*$)/g33const slotRE = /^v-slot(:|$)|^#/34const lineBreakRE = /[\r\n]/35const whitespaceRE = /\s+/g36const invalidAttributeRE = /[\s"'<>\/=]/37const decodeHTMLCached = cached(he.decode)38export const emptySlotScopeToken = `_empty_`39// configurable state40export let warn: any41let delimiters42let transforms43let preTransforms44let postTransforms45let platformIsPreTag46let platformMustUseProp47let platformGetTagNamespace48let maybeComponent49/* åå»º AST åç´ èç¹ */50export function createASTElement (/* ... */) {/* ... */}51/* è§£ææ¨¡ç */52export function parse (/* ... */) {/* ... */}53/* æ£æ¥ v-pre å±æ§ & æ·»å æ è®° */54function processPre (el) {/* ... */}55/* å¤çç®åå±æ§åè¡¨ */56function processRawAttrs (el) {/* ... */}57/* å¤çåç´ èç¹ */58export function processElement (/* ... */) {/* ... */}59/* å¤ç key å±æ§ */60function processKey (el) {/* ... */}61/* å¤ç ref å±æ§ */62function processRef (el) {/* ... */}63/* å¤ç v-for å±æ§ */64export function processFor (el: ASTElement) {/* ... */}65/* v-for å±æ§è¡¨è¾¾å¼è§£æç»æ */66type ForParseResult = {67  // (item, index, arr) in target68  for: string;  // å¾ªç¯ç®æ (target)69  alias: string;  // å¾ªç¯å¯¹è±¡(item)70  iterator1?: string;  // index71  iterator2?: string;  // arr72};73/* è§£æ v-for å±æ§è¡¨è¾¾å¼ */74export function parseFor (exp: string): ?ForParseResult {/* ... */}75/* å¤ç v-ifãv-else-ifãv-else å±æ§ */76function processIf (el) {/* ... */}77/* å¤çæ¡ä»¶ç¼è¯(ifConditions åè¡¨) */78function processIfConditions (el, parent) {/* ... */}79/* è·ååé©±åç´ èç¹ */80function findPrevElement (children: Array<any>): ASTElement | void {/* ... */}81/* åç®æ èç¹æ·»å æ¡ä»¶ç¼è¯(ifConditions) */82export function addIfCondition (el: ASTElement, condition: ASTIfCondition) {/* ... */}83/* å¤ç v-once å±æ§ */84function processOnce (el) {/* ... */}85/* å¤çå¸¦ v-slot å±æ§æ ç¾ */86function processSlotContent (el) {/* ... */}87/* è·åææ§½åç§° */88function getSlotName (binding) {/* ... */}89/* å¤ç <slot> æ ç¾ */90function processSlotOutlet (el) {/* ... */}91/* å¤çç»ä»¶ç±»åå±æ§ */92function processComponent (el) {/* ... */}93/* å¤çèç¹å±æ§ */94function processAttrs (el) {/* ... */}95/* æ£æ¥æ¯å¦å¤äº v-for åè¡¨æ¸²æä¸ */96function checkInFor (el: ASTElement): boolean {/* ... */}97function parseModifiers (name: string): Object | void {/* ... */}98function makeAttrsMap (attrs: Array<Object>): Object {/* ... */}99/* æ£æ¥æ¯å¦ä¸ºçº¯ææ¬èç¹ */100function isTextTag (el): boolean {/* ... */}101/* æ£æ¥æ¯å¦ä¸ºç¹æ®åç´ æ ç¾ */102function isForbiddenTag (el): boolean {/* ... */}103function guardIESVGBug (attrs) {/* ... */}...

index.js

Source:index.js

...30        // return element31    }32    function processElement(element) {33        processSlotContent(element)34        processSlotOutlet(element)35        // debugger36        return element37    }38    function processSlotOutlet(el) {39        if (el.tag === 'slot') {40            // debugger41            el.slotName = `"${getBindingAttr(el, 'name')}"`42        }43    }44    function getBindingAttr(el, name) {45        let slotTarget = el.attrs[0] && el.attrs[0]['value']46        return slotTarget47    }48    function processSlotContent(el) {49        // debugger50        var slotTarget = getBindingAttr(el, 'slot')51        if (slotTarget) {52            el.slotTarget = slotTarget === '""' ? '"default"' : slotTarget...

slot.html.051d4bdd.js

Source:slot.html.051d4bdd.js

1const data = {2  "key": "v-27dfcba2",3  "path": "/vue/source-study/compile/topics/slot.html",4  "title": "\u63D2\u69FD",5  "lang": "en-US",6  "frontmatter": {},7  "excerpt": "",8  "headers": [9    {10      "level": 2,11      "title": "\u5E38\u89C4\u63D2\u69FD VS \u4F5C\u7528\u57DF\u63D2\u69FD",12      "slug": "\u5E38\u89C4\u63D2\u69FD-vs-\u4F5C\u7528\u57DF\u63D2\u69FD",13      "children": [14        {15          "level": 3,16          "title": "\u63D2\u69FD\u7684\u4F5C\u7528\u57DF",17          "slug": "\u63D2\u69FD\u7684\u4F5C\u7528\u57DF",18          "children": []19        },20        {21          "level": 3,22          "title": "\u63D2\u69FD VNode \u7684\u751F\u6210\u65B9\u5F0F",23          "slug": "\u63D2\u69FD-vnode-\u7684\u751F\u6210\u65B9\u5F0F",24          "children": []25        }26      ]27    },28    {29      "level": 2,30      "title": "\u521B\u5EFA AST \u65F6\u5904\u7406\u63D2\u69FD",31      "slug": "\u521B\u5EFA-ast-\u65F6\u5904\u7406\u63D2\u69FD",32      "children": [33        {34          "level": 3,35          "title": "processSlotContent \u5904\u7406\u63D2\u69FD\u5185\u5BB9",36          "slug": "processslotcontent-\u5904\u7406\u63D2\u69FD\u5185\u5BB9",37          "children": []38        },39        {40          "level": 3,41          "title": "processSlotOutlet \u5904\u7406\u63D2\u69FD\u6807\u7B7E",42          "slug": "processslotoutlet-\u5904\u7406\u63D2\u69FD\u6807\u7B7E",43          "children": []44        }45      ]46    },47    {48      "level": 2,49      "title": "\u751F\u6210 render \u51FD\u6570\u53CA\u8FD0\u884C\u65F6\u9636\u6BB5",50      "slug": "\u751F\u6210-render-\u51FD\u6570\u53CA\u8FD0\u884C\u65F6\u9636\u6BB5",51      "children": [52        {53          "level": 3,54          "title": "\u63D2\u69FD\u5185\u5BB9\u6570\u636E\u5BF9\u8C61\u4E0A\u7684 scopedSlots",55          "slug": "\u63D2\u69FD\u5185\u5BB9\u6570\u636E\u5BF9\u8C61\u4E0A\u7684-scopedslots",56          "children": []57        },58        {59          "level": 3,60          "title": "genSlot \u751F\u6210\u63D2\u69FD\u6807\u7B7E\u7684\u4EE3\u7801",61          "slug": "genslot-\u751F\u6210\u63D2\u69FD\u6807\u7B7E\u7684\u4EE3\u7801",62          "children": []63        },64        {65          "level": 3,66          "title": "\u8FD0\u884C\u65F6\u751F\u6210\u63D2\u69FD\u5185\u5BB9\u7684 VNode",67          "slug": "\u8FD0\u884C\u65F6\u751F\u6210\u63D2\u69FD\u5185\u5BB9\u7684-vnode",68          "children": []69        }70      ]71    },72    {73      "level": 2,74      "title": "\u793A\u4F8B",75      "slug": "\u793A\u4F8B",76      "children": [77        {78          "level": 3,79          "title": "\u7236\u7EC4\u4EF6",80          "slug": "\u7236\u7EC4\u4EF6",81          "children": []82        },83        {84          "level": 3,85          "title": "\u5B50\u7EC4\u4EF6",86          "slug": "\u5B50\u7EC4\u4EF6",87          "children": []88        },89        {90          "level": 3,91          "title": "\u7236\u7EC4\u4EF6\u7684 render \u51FD\u6570",92          "slug": "\u7236\u7EC4\u4EF6\u7684-render-\u51FD\u6570",93          "children": []94        },95        {96          "level": 3,97          "title": "\u5B50\u7EC4\u4EF6\u7684 render \u51FD\u6570",98          "slug": "\u5B50\u7EC4\u4EF6\u7684-render-\u51FD\u6570",99          "children": []100        }101      ]102    }103  ],104  "filePathRelative": "vue/source-study/compile/topics/slot.md"105};...

transformSlotOutlet.js

Source:transformSlotOutlet.js

...5import { camelize } from '../../shared/index.js'6export const transformSlotOutlet = (node, context) => {7  if (isSlotOutlet(node)) {8    const { children, loc } = node9    const { slotName, slotProps } = processSlotOutlet(node, context)10    const slotArgs = [11      context.prefixIdentifiers ? `_ctx.$slots` : `$slots`,12      slotName,13      '{}',14      'undefined',15      'true'16    ]17    let expectedLen = 218    if (slotProps) {19      slotArgs[2] = slotProps20      expectedLen = 321    }22    if (children.length) {23      slotArgs[3] = createFunctionExpression([], children, false, false, loc)...

movie.js

Source:movie.js

1const { processSlotOutlet } = require("@vue/compiler-core");2const axios = require("axios");3const {OMDB_API_KEY} = process.env4exports.handler = async function _fetchMovie(event) {5  console.log(event)6  const payload = JSON.parse(event.body)7  const { title, type, year, page, id } = payload;8  const url = id9    ? `https://www.omdbapi.com/?apikey=${OMDB_API_KEY}&i=${id}`10    : `https://www.omdbapi.com/?apikey=${OMDB_API_KEY}&s=${title}&type=${type}&y=${year}&page=${page}`;11  try {12    const { data } = await axios.get(url);13    if (data.Error) {14      return {15        statusCode: 400,16        body: data.Error17      }18    }19    return {20      statusCode: 200,21      body: JSON.stringify(data)22    }23  } catch (error) {24    return {25      statusCode: error.response.status,26      body: error.message27    }28  }...

processElement.js

Source:processElement.js

...11    !element.attrsList.length12  )13  processRef(element)  // ref å±æ§14  processSlotContent(element)  // å¤çå¸¦ v-slot å±æ§æ ç¾15  processSlotOutlet(element)  // å¤ç <slot> æ ç¾16  processComponent(element)  // å¤çç»ä»¶ç±»åå±æ§17  // è°ç¨é¢å¤ç transforms18  for (let i = 0; i < transforms.length; i++) {19    element = transforms[i](element, options) || element20  }21  22  processAttrs(element)23  return element...

processSlotOutlet.js

Source:processSlotOutlet.js

1/* å¤ç <slot> æ ç¾ */2function processSlotOutlet (el) {3  if (el.tag === 'slot') {4    el.slotName = getBindingAttr(el, 'name')5    // key on <slot> warning ...6  }...

Using AI Code Generation

1const { Playwright } = require('playwright-core');2const { BrowserContext } = require('playwright-core/lib/server/browserContext');3const { Page } = require('playwright-core/lib/server/page');4const { Frame } = require('playwright-core/lib/server/frames');5const playwright = new Playwright();6const browser = await playwright.chromium.launch();7const context = await browser.newContext();8const page = await context.newPage();9const internal = page._delegate;10const slot = await internal.processSlotOutlet('slot-name');11console.log(slot);12const internalFrame = frame._delegate;13const slot = await internalFrame.processSlotOutlet('slot-name');14console.log(slot);15const internalContext = context._delegate;16const slot = await internalContext.processSlotOutlet('slot-name');17console.log(slot);18const internalBrowser = browser._delegate;19const slot = await internalBrowser.processSlotOutlet('slot-name');20console.log(slot);21const slot = await playwright.processSlotOutlet('slot-name');22console.log(slot);23const slot = await Playwright.processSlotOutlet('slot-name');24console.log(slot);25const slot = await Playwright.prototype.processSlotOutlet('slot-name');26console.log(slot);27const slot = await Playwright.processSlotOutlet('slot-name');28console.log(slot);29const slot = await Playwright.prototype.processSlotOutlet('slot-name');30console.log(slot);31const slot = await BrowserContext.processSlotOutlet('slot-name');32console.log(slot);33const slot = await BrowserContext.prototype.processSlotOutlet('slot-name');34console.log(slot);35const slot = await Page.processSlotOutlet('slot-name');36console.log(slot);37const slot = await Page.prototype.processSlotOutlet('slot-name');38console.log(slot);

Using AI Code Generation

1const { processSlotOutlet } = require('playwright/lib/server/chromium/crPage');2const { Page } = require('playwright/lib/server/chromium/crPage');3const { Frame } = require('playwright/lib/server/chromium/crPage');4const frame = await page.mainFrame();5const page = await frame.page();6const slot = await frame.$('#slot');7const slotContent = await slot.innerHTML();8const slotParent = await slot.parentElement();9const slotParentContent = await slotParent.innerHTML();10const slotParentParent = await slotParent.parentElement();11const slotParentParentContent = await slotParentParent.innerHTML();12const slotParentParentParent = await slotParentParent.parentElement();13const slotParentParentParentContent = await slotParentParentParent.innerHTML();14const slotParentParentParentParent = await slotParentParentParent.parentElement();15const slotParentParentParentParentContent = await slotParentParentParentParent.innerHTML();16const slotParentParentParentParentParent = await slotParentParentParentParent.parentElement();17const slotParentParentParentParentParentContent = await slotParentParentParentParentParent.innerHTML();18const slotParentParentParentParentParentParent = await slotParentParentParentParentParent.parentElement();19const slotParentParentParentParentParentParentContent = await slotParentParentParentParentParentParent.innerHTML();

Using AI Code Generation

1const { processSlotOutlet } = require("@playwright/test/lib/server/slot");2const { processSlot } = require("@playwright/test/lib/server/slot");3const { processSlot } = require("@playwright/test/lib/server/slot");4const { processSlot } = require("@playwright/test/lib/server/slot");5const { processSlot } = require("@playwright/test/lib/server/slot");6const { processSlot } = require("@playwright/test/lib/server/slot");7const { processSlot } = require("@playwright/test/lib/server/slot");8const { processSlot } = require("@playwright/test/lib/server/slot");9const { processSlot } = require("@playwright/test/lib/server/slot");10const { processSlot } = require("@playwright/test/lib/server/slot");11const { processSlot } = require("@playwright/test/lib/server/slot");12const { processSlot } = require("@playwright/test/lib/server/slot");13const { processSlot } = require("@playwright/test/lib/server/slot");14const { processSlot } = require("@playwright/test/lib/server/slot");15const { processSlot } = require("@playwright/test/lib/server/slot");16const { processSlot } = require("@playwright/test/lib/server/slot");17const { processSlot } = require("@playwright/test/lib/server/slot");18const { process

Using AI Code Generation

1const { processSlotOutlet } = require('playwright/lib/server/slot.js');2const { Page } = require('playwright/lib/server/page.js');3const page = new Page(null, null, null);4const slot = page._addSlot('test');5const outlet = processSlotOutlet(slot, 'test');6console.log(outlet);7const { ChannelOwner } = require('./channelOwner.js');8class Slot extends ChannelOwner {9  constructor(parent, type, guid, initializer) {10    super(parent, type, guid, initializer);11  }12  async _initialize(initializer) {13    await super._initialize(initializer);14    this._page = this._scope;15  }16}17module.exports = { Slot };18class ChannelOwner {19  constructor(parent, type, guid, initializer) {20    this._parent = parent;21    this._type = type;22    this._guid = guid;23    this._initializer = initializer;24    this._channel = null;25    this._scope = null;26    this._guid = guid;27    this._delegates = new Set();28    this._disposed = false;29  }30  async _initialize(initializer) {31    this._scope = this._parent;32    while (this._scope && !this._scope._isPage && !this._scope._isBrowserContext && !this._scope._isBrowser)33      this._scope = this._scope._parent;

Using AI Code Generation

1const { processSlotOutlet } = require('playwright/lib/server/slotOutlets');2const outlet = processSlotOutlet({name: 'mySlot', args: {a: 1, b: 2}});3console.log(outlet);4const { processSlotOutlet } = require('playwright/lib/server/slotOutlets');5const outlet = processSlotOutlet({name: 'mySlot', args: {a: 1, b: 2}});6console.log(outlet);7const { processSlotOutlet } = require('playwright/lib/server/slotOutlets');8const outlet = processSlotOutlet({name: 'mySlot', args: {a: 1, b: 2}});9console.log(outlet);10const { processSlotOutlet } = require('playwright/lib/server/slotOutlets');11const outlet = processSlotOutlet({name: 'mySlot', args: {a: 1, b: 2}});12console.log(outlet);13const { processSlotOutlet } = require('playwright/lib/server/slotOutlets');14const outlet = processSlotOutlet({name: 'mySlot', args: {a: 1, b: 2}});15console.log(outlet);16const { processSlotOutlet } = require('playwright/lib/server/slotOutlets');17const outlet = processSlotOutlet({name: 'mySlot', args: {a: 1, b: 2}});18console.log(outlet);19const { processSlotOutlet } = require('playwright/lib/server/slotOutlets');20const outlet = processSlotOutlet({name: 'mySlot', args: {a: 1, b: 2}});21console.log(outlet);22const { processSlotOutlet } = require('playwright/lib/server/slotOutlets');23const outlet = processSlotOutlet({name: 'mySlot', args: {a: 1, b: 2}});24console.log(outlet);

Using AI Code Generation

1const { processSlotOutlet } = require('playwright/lib/client/slotRegistry');2const slotRegistry = processSlotOutlet('slotRegistry');3const { createSlot } = slotRegistry;4const slot = createSlot('mySlot');5await slot.emit('myEvent', { foo: 'bar' });6await page.exposeBinding('mySlot', (source, event) => {7});8await page.evaluate(() => {9  const { processSlotOutlet } = window['playwrightLib'];10  const slotRegistry = processSlotOutlet('slotRegistry');11  const { createSlot } = slotRegistry;12  const slot = createSlot('mySlot');13  slot.listen('myEvent', event => {14    window['mySlot'](event);15  });16});17createSlot(name: string): Slot18emit(name: string, event: any): void19listen(name: string, callback: (event: any) => void): void

Using AI Code Generation

1const { PlaywrightInternal } = require('playwright');2const { Slot } = require('playwright');3const slot = new Slot('slot', 'test');4const slotOutlet = new Slot.Outlet(slot);5const slotImpl = new PlaywrightInternal().processSlotOutlet(slotOutlet);6console.log(slotImpl);

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?

firefox browser does not start in playwright

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

firefox browser does not start in playwright

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

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

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

Blogs

Check out the latest blogs from LambdaTest on this topic:

A Comprehensive Guide On JUnit 5 Extensions

JUnit is one of the most popular unit testing frameworks in the Java ecosystem. The JUnit 5 version (also known as Jupiter) contains many exciting innovations, including support for new features in Java 8 and above. However, many developers still prefer to use the JUnit 4 framework since certain features like parallel execution with JUnit 5 are still in the experimental phase.

Starting & growing a QA Testing career

The QA testing career includes following an often long, winding road filled with fun, chaos, challenges, and complexity. Financially, the spectrum is broad and influenced by location, company type, company size, and the QA tester’s experience level. QA testing is a profitable, enjoyable, and thriving career choice.

What is Selenium Grid & Advantages of Selenium Grid

Manual cross browser testing is neither efficient nor scalable as it will take ages to test on all permutations & combinations of browsers, operating systems, and their versions. Like every developer, I have also gone through that ‘I can do it all phase’. But if you are stuck validating your code changes over hundreds of browsers and OS combinations then your release window is going to look even shorter than it already is. This is why automated browser testing can be pivotal for modern-day release cycles as it speeds up the entire process of cross browser compatibility.

Test strategy and how to communicate it

I routinely come across test strategy documents when working with customers. They are lengthy—100 pages or more—and packed with monotonous text that is routinely reused from one project to another. Yawn once more— the test halt and resume circumstances, the defect management procedure, entrance and exit criteria, unnecessary generic risks, and in fact, one often-used model replicates the requirements of textbook testing, from stress to systems integration.

Acquiring Employee Support for Change Management Implementation

Enterprise resource planning (ERP) is a form of business process management software—typically a suite of integrated applications—that assists a company in managing its operations, interpreting data, and automating various back-office processes. The introduction of a new ERP system is analogous to the introduction of a new product into the market. If the product is not handled appropriately, it will fail, resulting in significant losses for the business. Most significantly, the employees’ time, effort, and morale would suffer as a result of the procedure.

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.