Emulation

Introduction

With Playwright you can test your app on any browser as well as emulate a real device such as a mobile phone or tablet. Simply configure the devices you would like to emulate and Playwright will simulate the browser behavior such as "userAgent", "screenSize", "viewport" and if it "hasTouch" enabled. You can also emulate the "geolocation", "locale" and "timezone" for all tests or for a specific test as well as set the "permissions" to show notifications or change the "colorScheme".

Devices

Playwright comes with a registry of device parameters using playwright.devices for selected desktop, tablet and mobile devices. It can be used to simulate browser behavior for a specific device such as user agent, screen size, viewport and if it has touch enabled. All tests will run with the specified device parameters.

• Test
• Library

playwright.config.ts

import { defineConfig, devices } from '@playwright/test'; // import devices

export default defineConfig({
  projects: [
    {
      name: 'chromium',
      use: {
        ...devices['Desktop Chrome'],
      },
    },
    {
      name: 'Mobile Safari',
      use: {
        ...devices['iPhone 13'],
      },
    },
  ],
});

Viewport

The viewport is included in the device but you can override it for some tests with page.setViewportSize().

• Test
• Library

playwright.config.ts

import { defineConfig, devices } from '@playwright/test';

export default defineConfig({
  projects: [
    {
      name: 'chromium',
      use: {
        ...devices['Desktop Chrome'],
        // It is important to define the `viewport` property after destructuring `devices`,
        // since devices also define the `viewport` for that device.
        viewport: { width: 1280, height: 720 },
      },
    },
  ]
});

Test file:

• Test
• Library

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test.use({
  viewport: { width: 1600, height: 1200 },
});

test('my test', async ({ page }) => {
  // ...
});

The same works inside a test file.

• Test
• Library

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test.describe('specific viewport block', () => {
  test.use({ viewport: { width: 1600, height: 1200 } });

  test('my test', async ({ page }) => {
    // ...
  });
});

isMobile

Whether the meta viewport tag is taken into account and touch events are enabled.

playwright.config.ts

import { defineConfig, devices } from '@playwright/test';

export default defineConfig({
  projects: [
    {
      name: 'chromium',
      use: {
        ...devices['Desktop Chrome'],
        // It is important to define the `isMobile` property after destructuring `devices`,
        // since devices also define the `isMobile` for that device.
        isMobile: false,
      },
    },
  ]
});

Locale & Timezone

Emulate the browser Locale and Timezone which can be set globally for all tests in the config and then overridden for particular tests.

playwright.config.ts

import { defineConfig } from '@playwright/test';

export default defineConfig({
  use: {
    // Emulates the browser locale.
    locale: 'en-GB',

    // Emulates the browser timezone.
    timezoneId: 'Europe/Paris',
  },
});

• Test
• Library

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test.use({
  locale: 'de-DE',
  timezoneId: 'Europe/Berlin',
});

test('my test for de lang in Berlin timezone', async ({ page }) => {
  await page.goto('https://www.bing.com');
  // ...
});

Note that this only affects the browser timezone and locale, not the test runner timezone. To set the test runner timezone, you can use the TZ environment variable.

Permissions

Allow app to show system notifications.

• Test
• Library

playwright.config.ts

import { defineConfig } from '@playwright/test';

export default defineConfig({
  use: {
    // Grants specified permissions to the browser context.
    permissions: ['notifications'],
  },
});

Allow notifications for a specific domain.

• Test
• Library

tests/example.spec.ts

import { test } from '@playwright/test';

test.beforeEach(async ({ context }) => {
  // Runs before each test and signs in each page.
  await context.grantPermissions(['notifications'], { origin: 'https://skype.com' });
});

test('first', async ({ page }) => {
  // page has notifications permission for https://skype.com.
});

Revoke all permissions with browserContext.clearPermissions().

// Library
await context.clearPermissions();

Geolocation

Grant "geolocation" permissions and set geolocation to a specific area.

playwright.config.ts

import { defineConfig } from '@playwright/test';

export default defineConfig({
  use: {
    // Context geolocation
    geolocation: { longitude: 12.492507, latitude: 41.889938 },
    permissions: ['geolocation'],
  },
});

• Test
• Library

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test.use({
  geolocation: { longitude: 41.890221, latitude: 12.492348 },
  permissions: ['geolocation'],
});

test('my test with geolocation', async ({ page }) => {
  // ...
});

Change the location later:

• Test
• Library

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test.use({
  geolocation: { longitude: 41.890221, latitude: 12.492348 },
  permissions: ['geolocation'],
});

test('my test with geolocation', async ({ page, context }) => {
  // overwrite the location for this test
  await context.setGeolocation({ longitude: 48.858455, latitude: 2.294474 });
});

Note you can only change geolocation for all pages in the context.

Color Scheme and Media

Emulate the users "colorScheme". Supported values are 'light' and 'dark'. You can also emulate the media type with page.emulateMedia().

playwright.config.ts

import { defineConfig } from '@playwright/test';

export default defineConfig({
  use: {
    colorScheme: 'dark',
  },
});

• Test
• Library

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test.use({
  colorScheme: 'dark' // or 'light'
});

test('my test with dark mode', async ({ page }) => {
  // ...
});

User Agent

The User Agent is included in the device and therefore you will rarely need to change it however if you do need to test a different user agent you can override it with the userAgent property.

• Test
• Library

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test.use({ userAgent: 'My user agent' });

test('my user agent test', async ({ page }) => {
  // ...
});

Offline

Emulate the network being offline.

playwright.config.ts

import { defineConfig } from '@playwright/test';

export default defineConfig({
  use: {
    offline: true
  },
});

JavaScript Enabled

Emulate a user scenario where JavaScript is disabled.

• Test
• Library

tests/example.spec.ts

import { test, expect } from '@playwright/test';

test.use({ javaScriptEnabled: false });

test('test with no JavaScript', async ({ page }) => {
  // ...
});