Discover AI-native insights at Testμ Conference‘25

How to use setActiveInstance method in Playwright Internal

Best JavaScript code snippet using playwright-internal

BlockChart.js

...51		return Math.max(acc, cells[node.id].row) 52	}, 0);53	const saveBlock = data => {54		dispatch("block/upsert", {block: data, insertAbove: (activeInstance && activeInstance.insertAbove) || undefined});55		setActiveInstance(null);56	}57	const deleteBlock = () => {58		if (activeInstance.id !== undefined)59			dispatch("block/delete", activeInstance);60		setActiveInstance(null);61	}62	let skip = 0;63	const renderCell = (r, c, cell) => {64		const cellStyles = "btn m-2 p-4 flex-grow-1 block-button text-dark " + (65			(cell.name === "Include" && "btn-outline-success") || 66			(cell.name === "Exclude" && "btn-outline-danger") ||67			"btn-outline-primary"68		);69		const retentionText = cell.retention && cell.retention.retentionType !== "none"70			? `retain ${cell.retention.retentionType} as ${cell.retention.retentionVar}`71			: "";72		const name = retentionText73			? <span>{cell.name}<br/>&#8595;<br/>{retentionText}</span>74			: cell.name;75		return <td key={r+":"+c} colSpan={cell.span} className="text-center" style={{height: "1px"}}>76			<div className="h-100 w-100 d-flex flex-column">77				{ r !== 1 && !cell.isLeaf && <div>78					<DropdownButton title="&#8595;" size="sm" variant="outline-primary" className="m-2 no-caret">79						<Dropdown.Item href="#" onClick={e => setActiveInstance({parentId: cell.parentId})}>Add Branch</Dropdown.Item>80						<Dropdown.Item href="#" onClick={e => setActiveInstance({parentId: cell.parentId, insertAbove: cell.id})}>Insert Block</Dropdown.Item>81					</DropdownButton>82				</div> }83				{ cell.isLeaf && <div>84					<Button size="sm" variant="outline-primary" className="m-2"85						onClick={e => setActiveInstance({parentId: cell.parentId})}86					>&#8595;</Button>87				</div> }88				<button className={cellStyles} onClick={e => {89					if (cell.isLeaf) {90						saveBlock({91							id: cell.parentId, 92							exclude: cell.name === "Exclude" ? false : true93						});94					} else if (cell.id !=="root" && !cell.isLeaf) {95						setActiveInstance({id: cell.id, parentId: cell.parentId})96					};97				}}>98					{name}99				</button>100				101				{ cell.patients !== undefined && !cell.isLeaf && <div>102					<Badge variant="primary" size="sm">{cell.patients} {cell.patients !== 1 ? "Patients" : "Patient"}</Badge>103				</div> }104				{ cell.patients !== undefined && cell.isLeaf && <div>105					<Badge variant="success" size="sm">Cohort:<br/>{cell.patients} {cell.patients !== 1 ? "Patients" : "Patient"}</Badge>106				</div> }107			</div>108		</td>;109	}110	const renderRow = r => {111		let skip = 0;112		return <tr key={r} className="" style={{height: "100%"}}>{113			 _.range(1, colCount).map( c => {114				 if (skip) {115					skip -=1;116					return;117				 }118				const cell = _.find(cells, cell => cell.row === r && cell.col === c);119				if (cell) {120					skip = cell.span-1;121					return renderCell(r, c, cell) 122				} else {123					return <td key={r+":"+c}></td>;124				}125			})126		}</tr>127	}128	129	const getRelativeOptions = (blockId, blocks) => {130		let relativeOptions = [];131		const block = blocks.find( b => b.id === blockId);132		block.retention && block.retention.retentionVar && 133			block.definition.fields.forEach( field => {134				relativeOptions.push({135					retentionVar: block.retention.retentionVar,136					fieldType: field.type,137					fieldName: field.name || field.id,138					value: [block.id, field.id].join("."),139					label: [block.retention.retentionVar, field.name || field.id].join(".")140				})141			});142		143		return block.parentId !== null144			? relativeOptions.concat( getRelativeOptions(block.parentId, blocks) )145			: relativeOptions;146	}147	const renderModal = () => {148		const data = blocks.find( b => b.id === activeInstance.id) || {};149		const retentionVar = data.retention && data.retention.retentionType !== "none" ? data.retention.retentionVar : "";150		const usedVars = blocks151			.filter( b => b.retention && b.retention.retentionType !== "none" && 152				b.retention.retentionVar && 153				b.retention.retentionVar !== retentionVar154			)155			.map( b => b.retention.retentionVar );156		const relativeOptions = data.parentId !== null ? getRelativeOptions(activeInstance.parentId, blocks) : [];157		const isReferenced = blocks.find( b => {158			return b.rules && b.rules.find( r => {159				return r.restrictions && r.restrictions.find( rs => {160					return (rs.compareTo && rs.compareTo.split(".")[0] === activeInstance.id.toString()) ||161						(rs.target && rs.target.split(".")[0] === activeInstance.id.toString())162				})163			})164		});165		console.log(isReferenced)166		return <BlockEditor 167			id={activeInstance.id}168			parentId={activeInstance.parentId}169			data={data}170			definitions={definitions}171			usedVars={usedVars}172			onClose={e => setActiveInstance(null)}173			relativeOptions={relativeOptions}174			onSave={saveBlock}175			onDelete={deleteBlock}176			isReferenced={!!isReferenced}177		/>178	}179	return <div>180		<div className="container-fluid split">181			<table className="m-4"><tbody>182				{ _.range(1, rowCount+1).map( renderRow )}183			</tbody></table></div>184			{ activeInstance && renderModal() }185	</div>186	...

missionActions.js

Source: missionActions.js

...20                dispatch({type: "UPDATE_MISSIONS", missions: missionObject.missions})21                if(missionObject.missionInstanceId){22                    const instanceIndex = missionObject.missions.findIndex((mission) => mission._id === missionObject.missionInstanceId)23                    //dispatch( {type: "SET_INSTANCE", id: missionObject.missionInstanceId, imgSrc: missionObject.missions[instanceIndex].imgSrc})24                    dispatch(setActiveInstance(missionObject.missionInstanceId, missionObject.missions[instanceIndex].imgSrc))25                }else{26                    //dispatch( {type: "SET_INSTANCE", id: missionObject.missionInstanceId, imgSrc: missionObject.missions[instanceIndex].imgSrc})27                    dispatch(setActiveInstance(null, null))28                }29                //??30                resolve(res.data)31            }catch (e) {32                reject(e)     33            } 34        })35    }36    37}38export const createInstance = (missionId) => {39    return (dispatch, getState) => {40        return new Promise (async (resolve, reject) => {41            try {42                const res = await axios.post('/mission/createInstance', {_id: missionId})43                const missionInstance = res.data.missionInstance44                const imgSrc = res.data.imgSrc45                dispatch(setActiveInstance(missionInstance._id, imgSrc))46                refreshMissionsEmit(getState().party._id)47                resolve(missionInstance)48            }catch (e) {49                reject(e)     50            } 51        })52    }53}54export const deleteInstance = () => {55    return (dispatch, getState) => {56        return new Promise (async (resolve, reject) => {57            try {58                await axios.delete('/mission/deleteInstance')59    60                dispatch(authCheck())61                dispatch(getMissionList()) 62                63                refreshMissionsEmit(getState().party._id)64                resolve()65            }catch (e) {66                reject(e)     67            } 68        })69    }70    71}72export const finishInstance = () => {73    return (dispatch, getState) => {74        return new Promise (async (resolve, reject) => {75            try {76                const res = await axios.delete('/mission/finishInstance')77                78                dispatch(setActiveInstance(null, null))79                finishMissionEmit(res.data, getState().party._id) // send awards to socket to broadcast it to party ? only mission id to save data80                resolve(res.data)81            }catch (e) {82                reject(e)     83            } 84        })85    }86    87}88export const sendItemToMission = (item, partyId) => {89    return new Promise (async (resolve, reject) => {90        try {91            await axiosInstance.patch('/mission/sendItem/mission', {item: item._id})92            addItemEmit(item, partyId)...

model.services.ispec.js

Source: model.services.ispec.js

...36  describe('.createModelInstance()', function() {37    it('removes internal Arc properties', function() {38      var instance = given.modelInstance();39      // setActiveInstance used to add `type` property40      IAService.setActiveInstance(instance, CONST.MODEL_TYPE);41      return ModelService.createModelInstance(instance)42        .then(function(created) {43          return ModelDefinition.findById({ id: created.id })44            .$promise;45        })46        .then(function(found) {47          var properties = Object.keys(found);48          expect(properties).to.not.include('config');49          expect(properties).to.not.include('type');50        });51    });52  });53  describe('.updateModelInstance()', function() {54    it('removes internal Arc properties on update', function() {55      var instance = given.modelInstance();56      return ModelService.createModelInstance(instance)57        .then(function(created) {58          // setActiveInstance used to add `type` property59          IAService.setActiveInstance(created, CONST.MODEL_TYPE);60          return ModelService.updateModelInstance(created);61        })62        .then(function(updated) {63          return ModelDefinition.findById({ id: updated.id })64            .$promise;65        })66        .then(function(found) {67          var properties = Object.keys(found);68          expect(properties).to.not.include('config');69          expect(properties).to.not.include('type');70        });71    });72  });73  describe('.createModelProperty()', function() {74    it('creates new model property', function() {75      var instance = given.modelInstance();76      return ModelService.createModelInstance(instance)77        .then(function(created) {78          expect(created.properties).to.have.length.below(1);79          expect(created).to.have.property('id');80          // setActiveInstance used to add `type` property81          IAService.setActiveInstance(created, CONST.MODEL_TYPE);82          function getRandomNumber() {83            return Math.floor((Math.random() * 100) + 1);84          }85          var propConfig = {86            name:'propertyName' + getRandomNumber(),87            type: ['number'],88            facetName: CONST.NEW_MODEL_FACET_NAME,89            modelId: created.id90          };91          expect(propConfig).to.have.property('facetName');92          expect(propConfig).to.have.property('modelId');93          expect(PropertyService).to.exist;94          var newProperty = PropertyService95            .createModelProperty(propConfig)...

789.js

Source: 789.js

...36  describe('.createModelInstance()', function() {37    it('removes internal Arc properties', function() {38      var instance = given.modelInstance();39      // setActiveInstance used to add `type` property40      IAService.setActiveInstance(instance, CONST.MODEL_TYPE);41      return ModelService.createModelInstance(instance)42        .then(function(created) {43          return ModelDefinition.findById({ id: created.id })44            .$promise;45        })46        .then(function(found) {47          var properties = Object.keys(found);48          expect(properties).to.not.include('config');49          expect(properties).to.not.include('type');50        });51    });52  });53  describe('.updateModelInstance()', function() {54    it('removes internal Arc properties on update', function() {55      var instance = given.modelInstance();56      return ModelService.createModelInstance(instance)57        .then(function(created) {58          // setActiveInstance used to add `type` property59          IAService.setActiveInstance(created, CONST.MODEL_TYPE);60          return ModelService.updateModelInstance(created);61        })62        .then(function(updated) {63          return ModelDefinition.findById({ id: updated.id })64            .$promise;65        })66        .then(function(found) {67          var properties = Object.keys(found);68          expect(properties).to.not.include('config');69          expect(properties).to.not.include('type');70        });71    });72  });73  describe('.createModelProperty()', function() {74    it('creates new model property', function() {75      var instance = given.modelInstance();76      return ModelService.createModelInstance(instance)77        .then(function(created) {78          expect(created.properties).to.have.length.below(1);79          expect(created).to.have.property('id');80          // setActiveInstance used to add `type` property81          IAService.setActiveInstance(created, CONST.MODEL_TYPE);82          function getRandomNumber() {83            return Math.floor((Math.random() * 100) + 1);84          }85          var propConfig = {86            name:'propertyName' + getRandomNumber(),87            type: ['number'],88            facetName: CONST.NEW_MODEL_FACET_NAME,89            modelId: created.id90          };91          expect(propConfig).to.have.property('facetName');92          expect(propConfig).to.have.property('modelId');93          expect(PropertyService).to.exist;94          var newProperty = PropertyService95            .createModelProperty(propConfig)...

lifecycle.js

Source: lifecycle.js

1import { query } from '../utils'2import { Watcher } from '../observer/watcher'3import { patch } from '../vdom/patch'4export let activeInstance = null5function setActiveInstance(vm) {6    activeInstance = vm7}8export function initLifecycle(vm) {9    const options = vm.$options10    const parent = options.parent11    // å¨ç»ä»¶ä¸this.$parentè®¿é®ç¶ç»ä»¶12    vm.$parent = parent13    // å¨ç»ä»¶ä¸this.$parentè®¿é®æ ¹ç»ä»¶14    vm.$root = parent ? parent.$root : vm15}16export function lifecycleMixin(Vue) {17    Vue.prototype._update = function(vnode) {18        const vm = this19        setActiveInstance(vm)20        const prevVnode = vm._vnode;21        // æè½½22        if(!prevVNode) {23            vm.$el = patch(vm.$el, vnode)24        } else {25            // æ´æ°26            vm.$el = patch(prevVnode, vnode)27        }28        29        // ä¿åå½åvnode treeï¼ç¨äºæ¯è¾ã30        vm._vnode = vnode31        setActiveInstance(null)32    }33    // new Vue.$mount(options.el)34    Vue.prototype.$mount = function(el) {35        el = query(el)36        return mountComponent(this, el)37    }38}39export function mountComponent(vm, el) {40    // this.$el,ç»ä»¶çæ ¹åç´ 41    vm.$el = el42    // æ§è¡ç»ä»¶çbeforeMounté©å43    // å®éä¸æ¯ä»vmä¸è¯»åbeforeMounté©åå½æ°ï¼æ§è¡æ¶åå¥½æ¯æ°ç»è¿æ¯å½æ°çå¤ç44    callHook(vm, 'beforeMount')45    function updateComponent(vm, el) {...

auth.js

Source: auth.js

...23      if (resource.data.panel_accesses.length && resource.data.panel_accesses[0].objects.length)24        tempInstance.instanceId = resource.data.panel_accesses[0].objects[0].instance_id;25      tempInstance.instanceName = resource.data.panel_accesses[0].objects[0].name;26    }27    setActiveInstance({ ...activeInstance, ...tempInstance });28  }, [resource]);29  const user = {30    isLoading: resource.isLoading,31    isAuthenticated: !resource.isError,32    user: resource.data,33  };34  return <context.Provider value={{ user, activeInstance, setActiveInstance }}>{children}</context.Provider>;35};36const useAuth = () => useContext(context);...

index.js

Source: index.js

...12import { Navbar } from './components';13function mapDispatchToProps(dispatch) {14  return {15    actions: {16      setActiveInstance: name => dispatch(setActiveInstance(name)),17      toggleProgressBarVisible: isVisible => dispatch(toggleProgressBarVisible(isVisible)),18      fetchInstances: (statusUrl) => dispatch(fetchInstances(statusUrl)),19    }20  };21}22export default connect(23  createStructuredSelector({24    instances,25    activeInstanceName,26    urls,27    progressIsVisible,28    progressPercent,29    location30  }),...

setActiveInstance.test.js

Source: setActiveInstance.test.js

1import { setActiveInstance } from './setActiveInstance';2describe('features.actions', () => {3  it('can setActiveInstance', () => {4    const action = setActiveInstance('redis000');5    expect(action).toBeTruthy();6  });...

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch({ headless: false });4  const page = await browser.newPage();5  await page.waitForTimeout(2000);6  const newPage = await browser.newPage();7  await newPage.waitForTimeout(2000);8  await page.bringToFront();9  await page.waitForTimeout(2000);10  await browser.close();11})();12- **Yashika Kukreja** - _Initial work_ - [yashika51](

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const page = await browser.newPage();5  await browser.close();6})();7#### `Playwright.launch([options])`

Using AI Code Generation

1const { setActiveInstance } = require('playwright/lib/server/browserContext');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  await setActiveInstance(page);8  await page.click('text=About');9  await page.waitForLoadState('networkidle');10  await browser.close();11})();12[MIT](LICENSE)

Using AI Code Generation

1const {webkit, devices} = require('playwright');2(async () => {3  const browser = await webkit.launch();4  const context = await browser.newContext(devices['iPhone 11 Pro']);5  const page = await context.newPage();6  const page2 = await context.newPage();7  await page2.bringToFront();8  await page.bringToFront();9  await page.close();10  await page2.close();11  await context.close();12  await browser.close();13})();14const {webkit, devices} = require('playwright');15(async () => {16  const browser = await webkit.launch();17  const context = await browser.newContext(devices['iPhone 11 Pro']);18  const page = await context.newPage();19  const page2 = await context.newPage();20  await page2.bringToFront();21  await page.bringToFront();22  await page.close();23  await page2.close();24  await context.close();25  await browser.close();26})();

Using AI Code Generation

1const { chromium, webkit, firefox } = require('playwright');2const { setActiveInstance } = require('playwright/lib/server/browserType');3(async () => {4  const browser = await chromium.launch();5  const context = await browser.newContext();6  const page = await context.newPage();7  setActiveInstance(page);8  await browser.close();9})();

Using AI Code Generation

1const { _electron } = require('playwright');2const { electron } = require('playwright');3(async () => {4  const browser = await electron.launch();5  const page = await browser.newPage();6  await _electron.setActiveInstance(page);7  await page.evaluate(() => {8    const { dialog } = require('electron').remote;9    dialog.showMessageBox({ message: 'Hello, world!' });10  });11  await browser.close();12})();13#### electron.launch([options])14#### electron.connect([options])

Using AI Code Generation

1const { chromium } = require('playwright');2const { setActiveInstance } = require('playwright/lib/server/browserType');3(async () => {4  const browser = await chromium.launch({ headless: false });5  const page = await browser.newPage();6  setActiveInstance(browser);7  await browser.close();8})();9#### **setActiveInstance()**10#### **newContext()**11const { chromium } = require('playwright');12const { setActiveInstance } = require('playwright/lib/server/browserType');13const { newContext } = require('playwright/lib/server/browser');14(async () => {15  const browser = await chromium.launch({ headless: false });16  const page = await browser.newPage();17  setActiveInstance(browser);18  const context = await newContext(browser);19  const page2 = await context.newPage();20  await browser.close();21})();22#### **newPage()**23const { chromium } = require('playwright');24const { setActiveInstance } = require('playwright/lib/server/browserType');25const { newContext } = require('playwright/lib/server/browser');26const { newPage } = require('playwright/lib/server/browserContext');27(async () => {

Using AI Code Generation

1const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');2const { chromium, webkit, firefox } = require('playwright');3const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');4const { chromium, webkit, firefox } = require('playwright');5const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');6const { chromium, webkit, firefox } = require('playwright');7const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');8const { chromium, webkit, firefox } = require('playwright');9const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');10const { chromium, webkit, firefox } = require('playwright');11const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');12const { chromium, webkit, firefox } = require('playwright');13const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');14const { chromium, webkit, firefox } = require('playwright');15const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');16const { chromium, webkit, firefox } = require('playwright');17const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');18const { chromium, webkit, firefox } = require('playwright');19const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');20const { chromium, webkit, firefox } = require('playwright');21const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');22const { chromium, webkit, firefox } = require('playwright');23const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');24const { chromium, webkit, firefox } = require('playwright');25const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require('@cucumber/cucumber');26const { chromium, webkit, firefox } = require('playwright');27const { setDefaultTimeout, setWorldConstructor, setDefaultTimeout } = require

Using AI Code Generation

1const playwright = require('playwright');2const { setActiveInstance } = require('playwright/lib/server/browserServer');3const { chromium } = require('playwright');4(async () => {5    const browser = await chromium.launch();6    await setActiveInstance(browser);7    const context = await browser.newContext();8    const page = await context.newPage();9    await page.screenshot({ path: `example.png` });10    await browser.close();11})();

StackOverFlow community discussions

Questions

Discussion

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

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

firefox browser does not start in playwright

Running Playwright in Azure Function

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

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

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

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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.
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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.