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How to use evaluateExpressionAndWaitForSignals method in Playwright Internal

Best JavaScript code snippet using playwright-internal

javascript.js

Source:javascript.js

...91    return evaluate(this._context, false92    /* returnByValue */93    , pageFunction, this, arg);94  }95  async evaluateExpressionAndWaitForSignals(expression, isFunction, returnByValue, arg) {96    const value = await evaluateExpressionAndWaitForSignals(this._context, returnByValue, expression, isFunction, this, arg);97    await this._context.doSlowMo();98    return value;99  }100  async getProperty(propertyName) {101    const objectHandle = await this.evaluateHandle((object, propertyName) => {102      const result = {103        __proto__: null104      };105      result[propertyName] = object[propertyName];106      return result;107    }, propertyName);108    const properties = await objectHandle.getProperties();109    const result = properties.get(propertyName);110    objectHandle.dispose();111    return result;112  }113  async getProperties() {114    if (!this._objectId) return new Map();115    return this._context._delegate.getProperties(this._context, this._objectId);116  }117  rawValue() {118    return this._value;119  }120  async jsonValue() {121    if (!this._objectId) return this._value;122    const utilityScript = await this._context.utilityScript();123    const script = `(utilityScript, ...args) => utilityScript.jsonValue(...args)`;124    return this._context._delegate.evaluateWithArguments(script, true, utilityScript, [true], [this._objectId]);125  }126  asElement() {127    return null;128  }129  dispose() {130    if (this._disposed) return;131    this._disposed = true;132    if (this._objectId) this._context._delegate.releaseHandle(this._objectId).catch(e => {});133  }134  toString() {135    return this._preview;136  }137  _setPreviewCallback(callback) {138    this._previewCallback = callback;139  }140  preview() {141    return this._preview;142  }143  _setPreview(preview) {144    this._preview = preview;145    if (this._previewCallback) this._previewCallback(preview);146  }147}148exports.JSHandle = JSHandle;149async function evaluate(context, returnByValue, pageFunction, ...args) {150  return evaluateExpression(context, returnByValue, String(pageFunction), typeof pageFunction === 'function', ...args);151}152async function evaluateExpression(context, returnByValue, expression, isFunction, ...args) {153  const utilityScript = await context.utilityScript();154  expression = normalizeEvaluationExpression(expression, isFunction);155  const handles = [];156  const toDispose = [];157  const pushHandle = handle => {158    handles.push(handle);159    return handles.length - 1;160  };161  args = args.map(arg => (0, _utilityScriptSerializers.serializeAsCallArgument)(arg, handle => {162    if (handle instanceof JSHandle) {163      if (!handle._objectId) return {164        fallThrough: handle._value165      };166      if (handle._disposed) throw new Error('JSHandle is disposed!');167      const adopted = context.adoptIfNeeded(handle);168      if (adopted === null) return {169        h: pushHandle(Promise.resolve(handle))170      };171      toDispose.push(adopted);172      return {173        h: pushHandle(adopted)174      };175    }176    return {177      fallThrough: handle178    };179  }));180  const utilityScriptObjectIds = [];181  for (const handle of await Promise.all(handles)) {182    if (handle._context !== context) throw new Error('JSHandles can be evaluated only in the context they were created!');183    utilityScriptObjectIds.push(handle._objectId);184  } // See UtilityScript for arguments.185  const utilityScriptValues = [isFunction, returnByValue, expression, args.length, ...args];186  const script = `(utilityScript, ...args) => utilityScript.evaluate(...args)`;187  try {188    return await context._delegate.evaluateWithArguments(script, returnByValue, utilityScript, utilityScriptValues, utilityScriptObjectIds);189  } finally {190    toDispose.map(handlePromise => handlePromise.then(handle => handle.dispose()));191  }192}193async function evaluateExpressionAndWaitForSignals(context, returnByValue, expression, isFunction, ...args) {194  return await context.waitForSignalsCreatedBy(() => evaluateExpression(context, returnByValue, expression, isFunction, ...args));195}196function parseUnserializableValue(unserializableValue) {197  if (unserializableValue === 'NaN') return NaN;198  if (unserializableValue === 'Infinity') return Infinity;199  if (unserializableValue === '-Infinity') return -Infinity;200  if (unserializableValue === '-0') return -0;201}202function normalizeEvaluationExpression(expression, isFunction) {203  expression = expression.trim();204  if (isFunction) {205    try {206      new Function('(' + expression + ')');207    } catch (e1) {...

jsHandleDispatcher.js

Source:jsHandleDispatcher.js

...36    }));37  }38  async evaluateExpression(params) {39    return {40      value: serializeResult(await this._object.evaluateExpressionAndWaitForSignals(params.expression, params.isFunction, true41      /* returnByValue */42      , parseArgument(params.arg)))43    };44  }45  async evaluateExpressionHandle(params) {46    const jsHandle = await this._object.evaluateExpressionAndWaitForSignals(params.expression, params.isFunction, false47    /* returnByValue */48    , parseArgument(params.arg));49    return {50      handle: _elementHandlerDispatcher.ElementHandleDispatcher.fromJSHandle(this._scope, jsHandle)51    };52  }53  async getProperty(params) {54    const jsHandle = await this._object.getProperty(params.name);55    return {56      handle: _elementHandlerDispatcher.ElementHandleDispatcher.fromJSHandle(this._scope, jsHandle)57    };58  }59  async getPropertyList() {60    const map = await this._object.getProperties();...

electronDispatcher.js

Source:electronDispatcher.js

...56  }57  async evaluateExpression(params) {58    const handle = await this._object._nodeElectronHandlePromise;59    return {60      value: (0, _jsHandleDispatcher.serializeResult)(await handle.evaluateExpressionAndWaitForSignals(params.expression, params.isFunction, true61      /* returnByValue */62      , (0, _jsHandleDispatcher.parseArgument)(params.arg)))63    };64  }65  async evaluateExpressionHandle(params) {66    const handle = await this._object._nodeElectronHandlePromise;67    const result = await handle.evaluateExpressionAndWaitForSignals(params.expression, params.isFunction, false68    /* returnByValue */69    , (0, _jsHandleDispatcher.parseArgument)(params.arg));70    return {71      handle: _elementHandlerDispatcher.ElementHandleDispatcher.fromJSHandle(this._scope, result)72    };73  }74  async close() {75    await this._object.close();76  }77}...

Using AI Code Generation

1const { evaluateExpressionAndWaitForSignals } = require('playwright/lib/server/supplements/recorder/recorderSupplement.js');2const { context } = require('playwright/lib/server/supplements/recorder/recorderSupplement.js');3const { page } = require('playwright/lib/server/supplements/recorder/recorderSupplement.js');4const expression = 'document.querySelector("button").click()';5const expression2 = 'document.querySelector("input").value = "Hello World"';6(async () => {7  await page.evaluate(expression);8  await page.evaluate(expression2);9  await evaluateExpressionAndWaitForSignals(expression);10})();11import { PlaywrightTestConfig } from '@playwright/test';12const config: PlaywrightTestConfig = {13  webServer: {14  },15  use: {16    viewport: { width: 1280, height: 720 },17  },18};19export default config;

Using AI Code Generation

1const playwright = require('playwright');2const { evaluateExpressionAndWaitForSignals } = playwright._internal;3(async () => {4  const browser = await playwright['chromium'].launch();5  const context = await browser.newContext();6  const page = await context.newPage();7  const expression = 'document.querySelector("div").innerText';8  const signals = ['load'];9  const result = await evaluateExpressionAndWaitForSignals(page, expression, signals);10  console.log(result);11  await browser.close();12})();

Using AI Code Generation

1const { evaluateExpressionAndWaitForSignals } = require('playwright/lib/server/chromium/crPage');2const { Page } = require('playwright/lib/server/chromium/crPage');3const { JSHandle } = require('playwright/lib/server/common/jsHandle');4const { CDPSession } = require('playwright/lib/protocol/channels');5const { Connection } = require('playwright/lib/protocol/connection');6const { helper } = require('playwright/lib/helper');7const { assert } = require('playwright/lib/helper');8const { debugError } = require('playwright/lib/helper');9const { debug } = require('playwright/lib/helper');10const page = new Page(new CDPSession(new Connection(), null, false), null);11const handle = new JSHandle(page, 'object', 'window', null);12const expression = 'window.location.reload()';13const isFunction = false;14const arg = undefined;15const returnByValue = false;16const awaitPromise = true;17const world = undefined;18const timeout = 30000;19const polling = 'raf';20const predicateBody = 'true';21const predicate = new Function('...args', `return (${predicateBody}).apply(null, args)`);22const noWaitAfter = false;23const signal = undefined;24(async () => {25    const result = await evaluateExpressionAndWaitForSignals(26    );27    console.log(result);28})();

Using AI Code Generation

1const { evaluateExpressionAndWaitForSignals } = require('playwright/lib/server/supplements/recorder/recorderSupplement');2const { signals } = require('playwright/lib/server/supplements/recorder/recorderSupplement');3const { firefox } = require('playwright/lib/server/supplements/recorder/recorderSupplement');4const { page } = require('playwright/lib/server/supplements/recorder/recorderSupplement');5const result = await evaluateExpressionAndWaitForSignals(page, 'document.querySelector("button")', signals.DOMContentLoaded);6if (result.error) {7  console.log('Error occured', result.error);8} else {9  console.log('Result', result.result);10}11const { evaluateExpressionAndWaitForSignals } = require('playwright/lib/server/supplements/recorder/recorderSupplement');12const { signals } = require('playwright/lib/server/supplements/recorder/recorderSupplement');13const { firefox } = require('playwright/lib/server/supplements/recorder/recorderSupplement');14const { page } = require('playwright/lib/server/supplements/recorder/recorderSupplement');15const { evaluateExpressionAndWaitForSignals } = require('playwright/lib/server/supplements/recorder/recorderSupplement');16const { signals } = require('playwright/lib/server/supplements/recorder/recorderSupplement');17const { firefox } = require('playwright/lib/server/supplements/recorder/recorderSupplement');18const { page } = require('playwright/lib/server/supplements/recorder/recorderSupplement');19const result = await evaluateExpressionAndWaitForSignals(page, 'document.querySelector("button")', signals.DOMContentLoaded);

Using AI Code Generation

1const { evaluateExpressionAndWaitForSignals } = require('playwright/lib/server/supplements/recorder/recorderSupplement.js');2const { Page } = require('playwright/lib/server/page.js');3const { Frame } = require('playwright/lib/server/frame.js');4const { JSHandle } = require('playwright/lib/server/jsHandle.js');5async function test() {6  const page = await browser.newPage();7  const expression = 'document.querySelector("div").textContent';8  const signals = {};9  const result = await evaluateExpressionAndWaitForSignals.call(page, expression, signals);10  console.log(result);11  await page.close();12}13test();

Using AI Code Generation

1const { evaluateExpressionAndWaitForSignals } = require('playwright/lib/server/evaluate');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const page = await browser.newPage();6  const result = await evaluateExpressionAndWaitForSignals(page, 'document.querySelector("text=Get started")', true, false, 10000);7  console.log(result);8  await browser.close();9})();10{11  result: {12    objectId: '{"injectedScriptId":1,"id":1}'13  },14  exceptionDetails: {15    stackTrace: {16    },17    exception: { type: 'object', subtype: 'error', className: 'Error', description: 'Error: Failed to find element matching selector "text=Get started"', objectId: '{"injectedScriptId":1,"id":2}' },18  },19}

Using AI Code Generation

1const { evaluateExpressionAndWaitForSignals } = require('playwright/lib/server/frames');2const { Page } = require('playwright/lib/server/page');3Page.prototype.evaluateExpressionAndWaitForSignals = evaluateExpressionAndWaitForSignals;4exports.evaluateExpressionAndWaitForSignals = async (page, expression, isFunction, arg) => {5    return await page.evaluateExpressionAndWaitForSignals(expression, isFunction, arg);6};7const { evaluateExpressionAndWaitForSignals } = require('./test');8const page = await browser.newPage();9const result = await evaluateExpressionAndWaitForSignals(page, '() => window.location.href', true);10console.log(result);11### `evaluateExpressionAndWaitForSignals(page, expression, isFunction, arg)`

Using AI Code Generation

1const {evaluateExpressionAndWaitForSignals} = require("playwright/lib/server/supplements/recorder/recorderSupplement");2(async () => {3  const page = await browser.newPage();4  const result = await evaluateExpressionAndWaitForSignals(page, 'document.querySelector("text=Get started")', 'click', 'click');5  console.log(result);6  await page.close();7})();

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