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How to use createOnceHandler method in Playwright Internal

Best JavaScript code snippet using playwright-internal

history_provider.js

Source:history_provider.js

...107      // teardown the listener108      teardownFn();109    });110    it('should call handler on state change', done => {111      createOnceHandler(history, done, loc => {112        expect(loc).to.be.a('object');113      });114      history.push({});115    });116    it('should pass location object to handler', done => {117      createOnceHandler(history, done, location => {118        expect(location.pathname).to.be.a('string');119        expect(location.hash).to.be.a('string');120        expect(location.state).to.be.an('object');121        expect(location.action).to.equal('push');122      });123      history.push(state);124    });125    it('should pass decompressed state to handler', done => {126      createOnceHandler(history, done, ({ state: curState }) => {127        expect(curState).to.eql(state);128      });129      history.push(state);130    });131    it('should pass in the previous location object to handler', done => {132      createOnceHandler(history, done, (location, prevLocation) => {133        expect(prevLocation.pathname).to.be.a('string');134        expect(prevLocation.hash).to.be.a('string');135        expect(prevLocation.state).to.be(null);136        expect(prevLocation.action).to.equal('push');137      });138      history.push(state);139    });140  });141  describe('resetOnChange', () => {142    // the history onChange handler was made async and now there's no way to know when the handler was called143    // TODO: restore these tests.144    it.skip('removes listeners', () => {145      const createHandler = () => {146        let callCount = 0;...

events.js

Source:events.js

...49      if (isUndef(cur.fns)) {50        cur = on[name] = createFnInvoker(cur, vm)51      }52      if (isTrue(event.once)) {53        cur = on[name] = createOnceHandler(event.name, cur, event.capture)54      }55      add(event.name, cur, event.capture, event.passive, event.params)56    } else if (cur !== old) {57      old.fns = cur58      on[name] = old59    }60  }61  for (name in oldOn) {62    if (isUndef(on[name])) {63      event = normalizeEvent(name)64      remove(event.name, oldOn[name], event.capture)65    }66  }67}...

Using AI Code Generation

1const { createOnceHandler } = require('playwright/lib/server/frames');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 frame = page.mainFrame();8  const handler = createOnceHandler(frame);9  frame.on('load', handler);10  await frame.waitForLoadState();11  await page.screenshot({ path: 'wikipedia.png' });12  await browser.close();13})();

Using AI Code Generation

1const { createOnceHandler } = require('playwright/lib/server/instrumentation');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const page = await browser.newPage();6  const onceHandler = createOnceHandler();7  await page.exposeBinding('onceHandler', onceHandler);8  await page.evaluate(async () => {9    window.addEventListener('message', event => {10      if (event.data.type === 'onceHandler') {11        window.onceHandler(event.data.data);12      }13    });14  });15  const result = await onceHandler(() => page.evaluate(() => {16    window.postMessage({ type: 'onceHandler', data: 42 }, '*');17  }));18  console.log(result);19  await browser.close();20})();21const { chromium } = require('playwright');22(async () => {23  const browser = await chromium.launch();24  const page = await browser.newPage();25  const result = await page.evaluate(() => {26    return new Promise(resolve => {27      window.addEventListener('message', event => {28        if (event.data.type === 'onceHandler') {29          resolve(event.data.data);30        }31      });32      window.postMessage({ type: 'onceHandler', data: 42 }, '*');33    });34  });35  console.log(result);36  await browser.close();37})();

Using AI Code Generation

1const { createOnceHandler } = require('@playwright/test/lib/server/progress');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 page.screenshot({ path: 'example.png' });8  await browser.close();9})();10const { createOnceHandler } = require('@playwright/test/lib/server/progress');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})();

Using AI Code Generation

1const { createOnceHandler } = require('@playwright/test/lib/server/trace/recorder/traceEvents');2const { Page } = require('@playwright/test/lib/server/page');3const { Frame } = require('@playwright/test/lib/server/frame');4const { createGuid } = require('@playwright/test/lib/utils/utils');5const { Context } = require('@playwright/test/lib/server/browserContext');6const { guid } = createGuid();7const context = new Context(null, guid);8const page = new Page(context, guid);9const frame = new Frame(page, guid);10const handler = createOnceHandler(frame, 'page');11frame._channel.on('page', handler);12frame._channel.emit('page', { frameId: '123' });13frame._channel.emit('page', { frameId: '456' });14frame._channel.off('page', handler);15frame._channel.emit('page', { frameId: '789' });16frame._channel.emit('page', { frameId: '101' });

Using AI Code Generation

1const { createOnceHandler } = require('playwright/lib/server/chromium/crConnection');2const { helper } = require('playwright/lib/helper');3const { chromium } = require('playwright');4(async () => {5  const browser = await chromium.launch();6  const page = await browser.newPage();7  await browser.close();8})();9const { createOnceHandler } = require('playwright/lib/server/chromium/crConnection');10const { helper } = require('playwright/lib/helper');11const { chromium } = require('playwright');12(async () => {13  const browser = await chromium.launch();14  const page = await browser.newPage();15  await browser.close();16})();

Using AI Code Generation

1const { createOnceHandler } = require('playwright/lib/server/frames');2const { Frame } = require('playwright/lib/server/page');3const handler = createOnceHandler();4const frame = new Frame();5frame._page._onFrameDetached.add(handler);6const frameDetached = handler.promise;7const frame = await frameDetached;8console.log(frame.url());

Using AI Code Generation

1const createOnceHandler = require('@playwright/test/lib/server/createOnceHandler');2const server = await testWorker._browserServer;3const handler = createOnceHandler(async (req, res) => {4  res.end('done');5});6server.route('/path', handler);7test('my test', async ({testInfo}) => {8  const testWorker = testInfo.workers[testInfo.workerIndex];9});

Using AI Code Generation

1const { createOnceHandler } = require('@playwright/test/lib/server/inspector');2const handler = createOnceHandler(event => console.log(event));3const WebSocket = require('ws');4const wss = new WebSocket.Server({ port: 8080 });5wss.on('connection', function connection(ws) {6  ws.on('message', function incoming(message) {7    const event = JSON.parse(message);8    handler(event);9  });10});11wss.on('listening', function listening() {12  console.log('Server started');13});14const WebSocket = require('ws');15ws.on('open', function open() {16  ws.send(JSON.stringify({ type: 'event1' }));17  ws.send(JSON.stringify({ type: 'event2' }));18  ws.send(JSON.stringify({ type: 'event1' }));19});20ws.on('message', function incoming(data) {21  console.log(data);22});23{ type: 'event1' }24{ type: 'event2' }25const { createOnceHandler } = require('@playwright/test/lib/server/inspector');26const handler = createOnceHandler(event => console.log(event));27const WebSocket = require('ws');28const wss = new WebSocket.Server({ port: 8080 });29wss.on('connection', function connection(ws) {30  ws.on('message', function incoming(message) {31    const event = JSON.parse(message);32    handler(event);33  });34});35wss.on('listening', function listening() {36  console.log('Server started');37});38const WebSocket = require('ws');39ws.on('open', function open() {40  ws.send(JSON.stringify({

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Playwright tutorial

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