How to use traceAPICoverage method in Playwright Internal

Best JavaScript code snippet using playwright-internal

utils.js

Source:utils.js

...20 * @param {Map<string, boolean>} apiCoverage21 * @param {string} className22 * @param {!Object} classType23 */24function traceAPICoverage(apiCoverage, className, classType) {25  className = className.substring(0, 1).toLowerCase() + className.substring(1);26  for (const methodName of Reflect.ownKeys(classType.prototype)) {27    const method = Reflect.get(classType.prototype, methodName);28    if (methodName === 'constructor' || typeof methodName !== 'string' || methodName.startsWith('_') || typeof method !== 'function')29      continue;30    apiCoverage.set(`${className}.${methodName}`, false);31    Reflect.set(classType.prototype, methodName, function(...args) {32      apiCoverage.set(`${className}.${methodName}`, true);33      return method.call(this, ...args);34    });35  }36  if (classType.Events) {37    for (const event of Object.values(classType.Events))38      apiCoverage.set(`${className}.emit(${JSON.stringify(event)})`, false);39    const method = Reflect.get(classType.prototype, 'emit');40    Reflect.set(classType.prototype, 'emit', function(event, ...args) {41      if (this.listenerCount(event))42        apiCoverage.set(`${className}.emit(${JSON.stringify(event)})`, true);43      return method.call(this, event, ...args);44    });45  }46}47const utils = module.exports = {48  recordAPICoverage: function(testRunner, api, disabled) {49    const coverage = new Map();50    for (const [className, classType] of Object.entries(api))51      traceAPICoverage(coverage, className, classType);52    testRunner.describe('COVERAGE', () => {53      for (const method of coverage.keys()) {54        (disabled.has(method) ? testRunner.xit : testRunner.it)(`public api '${method}' should be called`, async({page, server}) => {55          if (!coverage.get(method))56            throw new Error('NOT CALLED!');57        });58      }59    });60  },61  /**62   * @return {string}63   */64  projectRoot: function() {65    return PROJECT_ROOT;...

coverage-utils.js

Source:coverage-utils.js

...31 * @param {Object} events32 * @param {string} className33 * @param {!Object} classType34 */35function traceAPICoverage(apiCoverage, events, className, classType) {36  className = className.substring(0, 1).toLowerCase() + className.substring(1);37  if (!classType || !classType.prototype) {38    console.error(39      `Coverage error: could not find class for ${className}. Is src/api.ts up to date?`40    );41    process.exit(1);42  }43  for (const methodName of Reflect.ownKeys(classType.prototype)) {44    const method = Reflect.get(classType.prototype, methodName);45    if (46      methodName === 'constructor' ||47      typeof methodName !== 'string' ||48      methodName.startsWith('_') ||49      typeof method !== 'function'50    )51      continue;52    apiCoverage.set(`${className}.${methodName}`, false);53    Reflect.set(classType.prototype, methodName, function (...args) {54      apiCoverage.set(`${className}.${methodName}`, true);55      return method.call(this, ...args);56    });57  }58  if (events[classType.name]) {59    for (const event of Object.values(events[classType.name])) {60      if (typeof event !== 'symbol')61        apiCoverage.set(`${className}.emit(${JSON.stringify(event)})`, false);62    }63    const method = Reflect.get(classType.prototype, 'emit');64    Reflect.set(classType.prototype, 'emit', function (event, ...args) {65      if (typeof event !== 'symbol' && this.listenerCount(event))66        apiCoverage.set(`${className}.emit(${JSON.stringify(event)})`, true);67      return method.call(this, event, ...args);68    });69  }70}71const coverageLocation = path.join(__dirname, 'coverage.json');72const clearOldCoverage = () => {73  try {74    fs.unlinkSync(coverageLocation);75  } catch (error) {76    // do nothing, the file didn't exist77  }78};79const writeCoverage = (coverage) => {80  fs.writeFileSync(coverageLocation, JSON.stringify([...coverage.entries()]));81};82const getCoverageResults = () => {83  let contents;84  try {85    contents = fs.readFileSync(coverageLocation, { encoding: 'utf8' });86  } catch (error) {87    console.error('Warning: coverage file does not exist or is not readable.');88  }89  const coverageMap = new Map(JSON.parse(contents));90  return coverageMap;91};92const trackCoverage = () => {93  clearOldCoverage();94  const coverageMap = new Map();95  before(() => {96    const api = require('../lib/api');97    const events = require('../lib/Events');98    for (const [className, classType] of Object.entries(api))99      traceAPICoverage(coverageMap, events, className, classType);100  });101  after(() => {102    writeCoverage(coverageMap);103  });104};105module.exports = {106  trackCoverage,107  getCoverageResults,...

coverage.js

Source:coverage.js

...19 * @param {Object} events20 * @param {string} className21 * @param {!Object} classType22 */23function traceAPICoverage(apiCoverage, api, events) {24  const uninstalls = [];25  for (const [name, classType] of Object.entries(api)) {26    const className = name.substring(0, 1).toLowerCase() + name.substring(1);27    for (const methodName of Reflect.ownKeys(classType.prototype)) {28      const method = Reflect.get(classType.prototype, methodName);29      if (methodName === 'constructor' || typeof methodName !== 'string' || methodName.startsWith('_') || typeof method !== 'function')30        continue;31      apiCoverage.set(`${className}.${methodName}`, false);32      const override = function(...args) {33        apiCoverage.set(`${className}.${methodName}`, true);34        return method.call(this, ...args);35      };36      Object.defineProperty(override, 'name', { writable: false, value: methodName });37      Reflect.set(classType.prototype, methodName, override);38      uninstalls.push(() => Reflect.set(classType.prototype, methodName, method));39    }40    if (events[name]) {41      for (const event of Object.values(events[name])) {42        if (typeof event !== 'symbol')43          apiCoverage.set(`${className}.emit(${JSON.stringify(event)})`, false);44      }45      const method = Reflect.get(classType.prototype, 'emit');46      Reflect.set(classType.prototype, 'emit', function(event, ...args) {47        if (typeof event !== 'symbol' && this.listenerCount(event))48          apiCoverage.set(`${className}.emit(${JSON.stringify(event)})`, true);49        return method.call(this, event, ...args);50      });51      uninstalls.push(() => Reflect.set(classType.prototype, 'emit', method));52    }53  }54  return () => uninstalls.forEach(u => u());55}56/**57 * @param {string} browserName58 */59function apiForBrowser(browserName) {60  const events = require('../../packages/playwright-core/lib/client/events').Events;61  const api = require('../../packages/playwright-core/lib/client/api');62  const otherBrowsers = ['chromium', 'webkit', 'firefox'].filter(name => name.toLowerCase() !== browserName.toLowerCase());63  const filteredKeys = Object.keys(api).filter(apiName => {64    if (apiName.toLowerCase().startsWith('android'))65      return browserName === 'android';66    if (apiName.toLowerCase().startsWith('electron'))67      return browserName === 'electron';68    return browserName !== 'electron' && browserName !== 'android' &&69        !otherBrowsers.some(otherName => apiName.toLowerCase().startsWith(otherName));70  });71  const filteredAPI = {};72  for (const key of filteredKeys)73    filteredAPI[key] = api[key];74  return {75    api: filteredAPI,76    events77  }78}79/**80 * @param {string} browserName81 */82function installCoverageHooks(browserName) {83  const {api, events} = apiForBrowser(browserName);84  const coverage = new Map();85  const uninstall = traceAPICoverage(coverage, api, events);86  return {coverage, uninstall};87}88module.exports = {89  installCoverageHooks,...

Using AI Code Generation

1const playwright = require('playwright');2(async () => {3  const browser = await playwright['chromium'].launch();4  const context = await browser.newContext();5  const page = await context.newPage();6  await page.tracing.start({ screenshots: true, snapshots: true });7  await page.tracing.stop({ path: 'trace.zip' });8  await browser.close();9})();10![Coverage Tab](/images/coverage-tab.png)11![Filesystem Tab](/images/filesystem-tab.png)12![Filesystem Tab](/images/filesystem-tab.png)13![Filesystem Tab](/images/filesystem-tab.png)14![Filesystem Tab](/images/filesystem-tab.png)15![Filesystem Tab](/images/filesystem-tab.png)16![Filesystem Tab](/images/filesystem-tab.png)

Using AI Code Generation

1const { traceAPICoverage } = require('@playwright/test');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const context = await browser.newContext();6  await traceAPICoverage(context, async () => {7    const page = await context.newPage();8  });9  await context.close();10  await browser.close();11})();

Using AI Code Generation

1const { traceAPICoverage } = require('@playwright/test');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch();5  const context = await browser.newContext();6  await traceAPICoverage(context, {7  });8  const page = await context.newPage();9  const coverage = await context.stopTracing();10  console.log(JSON.stringify(coverage, null, 2));11  await browser.close();12})();13### `traceAPICoverage(context, options)`

Using AI Code Generation

1const { traceAPICoverage } = require('playwright/lib/server/chromium/crCoverage');2const { chromium } = require('playwright');3(async () => {4  const browser = await chromium.launch({ headless: false });5  const context = await browser.newContext();6  const page = await context.newPage();7  const coverage = await traceAPICoverage(page, async () => {8  });9  console.log(coverage);10  await browser.close();11})();12{13    "text": "window.bbcnews={\"page\":\"news\",\"article\":\".article\",\"articleBody\":\".article__body\",\"articleHeadline\":\".article__headline\",\"articleTimestamp\":\".article__timestamp\",\"articleTimestampLink\":\".article__timestamp a\",\"articleTimestampLinkText\":\".article__timestamp a span\",\"articleTimestampLinkIcon\":\".article__timestamp a svg\",\"articleTimestampLinkIconText\":\".article__timestamp a svg text\",\"articleTimestampLinkIconPath\":\".article__timestamp a svg path\",\"articleTimestampLinkIconCircle\":\".article__timestamp a svg circle\",\"articleTimestampLinkIconRect\":\".article__timestamp a svg rect\",\"articleTimestampLinkIconPolygon\":\".article__timestamp a svg polygon\",\"articleTimestampLinkIconEllipse\":\".article__timestamp a svg ellipse\",\"articleTimestampLinkIconLine\":\".article__timestamp a svg line\",\"articleTimestampLinkIconStop\":\".article__timestamp a svg stop\",\"articleTimestampLinkIconUse\":\".article__timestamp a svg use\",\"articleTimestampLinkIconG\":\".article__timestamp a svg g\",\"articleTimestampLinkIconDefs\":\".article__timestamp a svg defs\",\"articleTimestampLinkIconClipPath\":\".article__timestamp a svg clipPath\",\"articleTimestampLinkIconMask\":\".article__timestamp a svg mask\",\"articleTimestampLinkIconPattern\":\".article__timestamp a svg pattern\",\"articleTimestampLinkIconPath\":\".article__timestamp a svg path\",\"articleTimestampLinkIconImage\":\".article__timestamp a svg image\",\"articleTimestampLinkIconSymbol\":\".article__timestamp a svg symbol\",\"articleTimestampLinkIconDesc\":\".article__timestamp a svg desc\",\"articleTimestampLinkIconTitle\":\".article

Using AI Code Generation

1const playwright = require('playwright');2const { traceAPICoverage } = require('playwright/lib/server/traceViewer');3(async () => {4  const browser = await playwright.chromium.launch({ headless: false });5  const context = await browser.newContext();6  const page = await context.newPage();7  const coverage = await traceAPICoverage(page, async () => {8    await page.click('text=English');9  });10  console.log(coverage);11  await browser.close();12})();

Using AI Code Generation

1const { traceAPICoverage } = require('@playwright/test/lib/server/trace');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 traceAPICoverage(page, 'trace.json');8  await browser.close();9})();

Using AI Code Generation

1const { traceAPICoverage } = require('playwright-core/lib/server/traceViewer');2const { chromium } = require('playwright-core');3(async () => {4  const browser = await chromium.launch({5  });6  const context = await browser.newContext();7  const page = await context.newPage();8  await traceAPICoverage(page, async () => {9    await page.click('text="English"');10    await page.fill('css=[id="searchInput"]', 'Playwright');11    await page.click('css=[type="submit"]');12    await page.click('css=[id="n-randompage"]');13  });14  await browser.close();15})();16const { traceAPICoverage } = require('playwright-core/lib/server/traceViewer');17const { chromium } = require('playwright-core');18(async () => {19  const browser = await chromium.launch({20  });21  const context = await browser.newContext();22  const page = await context.newPage();23  await traceAPICoverage(page, async () => {24    await page.click('text="English"');25    await page.fill('css=[id="searchInput"]', 'Playwright');26    await page.click('css=[type="submit"]');27    await page.click('css=[id="n-randompage"]');28  });29  await browser.close();30})();

Using AI Code Generation

1const { traceAPICoverage } = require('playwright-core/lib/server/traceViewer');2const fs = require('fs');3const path = require('path');4const { chromium } = require('playwright-core');5(async () => {6  const browser = await chromium.launch();7  const context = await browser.newContext();8  const page = await context.newPage();9  await page.click('text=Docs');10  const coverage = await traceAPICoverage(page, async () => {11    await page.click('text=API');12  });13  fs.writeFileSync('coverage.json', JSON.stringify(coverage, null, 2));14  await browser.close();15})();16{17    {18    },19    {20    },21    {22    },23    {24    },25    {26    },27    {28    },29    {30    },31    {

Using AI Code Generation

1const { traceAPICoverage } = require('@playwright/test');2(async () => {3    onCoverage: (coverage) => {4      console.log(coverage);5    }6  });7})();8### traceAPICoverage(url, options)

Using AI Code Generation

1const playwright = require('playwright');2const { traceAPICoverage } = require('playwright/lib/internal/trace/recorder/apiCoverage');3const { chromium, webkit, firefox } = playwright;4(async () => {5  const browser = await chromium.launch({ headless: false });6  const context = await browser.newContext();7  const page = await context.newPage();8  await traceAPICoverage(page, async () => {9  });10  await browser.close();11})();12const playwright = require('playwright');13const { traceCoverage } = require('playwright/lib/internal/trace/recorder/coverage');14const { chromium, webkit, firefox } = playwright;15(async () => {16  const browser = await chromium.launch({ headless: false });17  const context = await browser.newContext();18  const page = await context.newPage();19  await traceCoverage(page, async () => {20  });21  await browser.close();22})();23You can download the trace viewer as a standalone application from the [releases](

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