playwright/intro-js.md at 96355b3a7a9724b1df0ed4cde4bdeee61925203d

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id	title
intro	Getting started

Playwright can either be used as a part of the Playwright Test (this guide), or as a Playwright Library.

Playwright Test was created specifically to accommodate the needs of the end-to-end testing. It does everything you would expect from the regular test runner, and more. Playwright test allows to:

Run tests across all browsers.
Execute tests in parallel.
Enjoy context isolation out of the box.
Capture videos, screenshots and other artifacts on failure.
Integrate your POMs as extensible fixtures.

Release notes

Installation

Playwright has its own test runner for end-to-end tests, we call it Playwright Test.

npm i -D @playwright/test
# install supported browsers
npx playwright install

You can optionally install only selected browsers, see installing browsers for more details. Or you can install no browsers at all and use existing browser channels.

First test

Create tests/foo.spec.js (or tests/foo.spec.ts for TypeScript) to define your test.

const { test, expect } = require('@playwright/test');

test('basic test', async ({ page }) => {
  await page.goto('https://playwright.dev/');
  const title = page.locator('.navbar__inner .navbar__title');
  await expect(title).toHaveText('Playwright');
});

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

test('basic test', async ({ page }) => {
  await page.goto('https://playwright.dev/');
  const title = page.locator('.navbar__inner .navbar__title');
  await expect(title).toHaveText('Playwright');
});

Now run your tests, assuming that test files are in the tests directory.

npx playwright test

Playwright Test just ran a test using Chromium browser, in a headless manner. Let's tell it to use headed browser:

npx playwright test --headed

What about other browsers? Let's run the same test using Firefox:

npx playwright test --browser=firefox

And finally, on all three browsers:

npx playwright test --browser=all

Refer to configuration section for configuring test runs in different modes with different browsers.

Writing assertions

Playwright Test uses expect library for test assertions. It extends it with the Playwright-specific matchers to achieve greater testing ergonomics.

Learn more about test assertions here.

Here is a quick example of using them:

// example.spec.js
const { test, expect } = require('@playwright/test');

test('my test', async ({ page }) => {
  await page.goto('https://playwright.dev/');

  // Expect a title "to contain" a substring.
  await expect(page).toHaveTitle(/Playwright/);

  // Expect an attribute "to be strictly equal" to the value.
  await expect(page.locator('text=Get Started').first()).toHaveAttribute('href', '/docs/intro');

  // Expect an element "to be visible".
  await expect(page.locator('text=Learn more').first()).toBeVisible();

  await page.click('text=Get Started');
  // Expect some text to be visible on the page.
  await expect(page.locator('text=System requirements').first()).toBeVisible();

  // Compare screenshot with a stored reference.
  expect(await page.screenshot()).toMatchSnapshot('get-started.png');
});

// example.spec.ts
import { test, expect } from '@playwright/test';

test('my test', async ({ page }) => {
  await page.goto('https://playwright.dev/');

  // Expect a title "to contain" a substring.
  await expect(page).toHaveTitle(/Playwright/);

  // Expect an attribute "to be strictly equal" to the value.
  await expect(page.locator('text=Get Started').first()).toHaveAttribute('href', '/docs/intro');

  // Expect an element "to be visible".
  await expect(page.locator('text=Learn more').first()).toBeVisible();

  await page.click('text=Get Started');
  // Expect some text to be visible on the page.
  await expect(page.locator('text=System requirements').first()).toBeVisible();

  // Compare screenshot with a stored reference.
  expect(await page.screenshot()).toMatchSnapshot('get-started.png');
});

Notice how running this test is saying:

Error: example.spec.ts-snapshots/get-started-chromium-darwin.png is missing in snapshots, writing actual.

That's because there was no golden file for your get-started.png snapshot. It is now created and is ready to be added to the repository. The name of the folder with the golden expectations starts with the name of your test file:

drwxr-xr-x  5 user  group  160 Jun  4 11:46 .
drwxr-xr-x  6 user  group  192 Jun  4 11:45 ..
-rw-r--r--  1 user  group  231 Jun  4 11:16 example.spec.ts
drwxr-xr-x  3 user  group   96 Jun  4 11:46 example.spec.ts-snapshots

To update your golden files, you can use the --update-snapshots parameter.

npx playwright test --update-snapshots

Using test fixtures

You noticed an argument { page } that the test above has access to:

test('basic test', async ({ page }) => {
  ...

test('basic test', async ({ page }) => {
  ...

We call these arguments fixtures. Fixtures are objects that are created for each test run. Playwright Test comes loaded with those fixtures, and you can add your own fixtures as well. When running tests, Playwright Test looks at each test declaration, analyses the set of fixtures the test needs and prepares those fixtures specifically for the test.

Here is a list of the pre-defined fixtures that you are likely to use most of the time:

Fixture	Type	Description
page	[Page]	Isolated page for this test run.
context	[BrowserContext]	Isolated context for this test run. The `page` fixture belongs to this context as well. Learn how to configure context.
browser	[Browser]	Browsers are shared across tests to optimize resources. Learn how to configure browser.
browserName	[string]	The name of the browser currently running the test. Either `chromium`, `firefox` or `webkit`.

Using test hooks

You can use test.beforeAll and test.afterAll hooks to set up and tear down resources shared between tests. And you can use test.beforeEach and test.afterEach hooks to set up and tear down resources for each test individually.

// example.spec.js
const { test, expect } = require('@playwright/test');

test.describe('feature foo', () => {
  test.beforeEach(async ({ page }) => {
    // Go to the starting url before each test.
    await page.goto('https://my.start.url/');
  });

  test('my test', async ({ page }) => {
    // Assertions use the expect API.
    await expect(page).toHaveURL('https://my.start.url/');
  });
});

// example.spec.ts
import { test, expect } from '@playwright/test';

test.describe('feature foo', () => {
  test.beforeEach(async ({ page }) => {
    // Go to the starting url before each test.
    await page.goto('https://my.start.url/');
  });

  test('my test', async ({ page }) => {
    // Assertions use the expect API.
    await expect(page).toHaveURL('https://my.start.url/');
  });
});

Command line

Following are the usual command line patterns. Learn more about the command line.

Run all the tests
```
npx playwright test
```

Run a single test file

npx playwright test tests/todo-page.spec.ts

Run a set of test files

npx playwright test tests/todo-page/ tests/landing-page/

Run files that have my-spec or my-spec-2 in the file name
```
npx playwright test my-spec my-spec-2
```

Run the test with the title

npx playwright test -g "add a todo item"

Run tests in headed browsers
```
npx playwright test --headed
```
Run tests in a particular browser (config-less mode)
```
npx playwright test --browser=webkit
```
Run tests in all browsers (config-less mode)
```
npx playwright test --browser=all
```
Disable parallelization
```
npx playwright test --workers=1
```
Choose a reporter
```
npx playwright test --reporter=dot
```

Run in debug mode with Playwright Inspector

# Linux/macOS
PWDEBUG=1 npx playwright test

# Windows with cmd.exe
set PWDEBUG=1
npx playwright test

# Windows with PowerShell
$env:PWDEBUG=1
npx playwright test

Ask for help
```
npx playwright test --help
```

Creating a configuration file

So far, we've looked at the zero-config operation of Playwright Test. For a real world application, it is likely that you would want to use a config.

Create playwright.config.ts (or playwright.config.js) to configure your tests. You can specify browser launch options, run tests in multiple browsers and much more with the config. Here is an example configuration that runs every test in Chromium, Firefox and WebKit, both Desktop and Mobile versions. Look for more options in the configuration section.

// playwright.config.js
// @ts-check
const { devices } = require('@playwright/test');

/** @type {import('@playwright/test').PlaywrightTestConfig} */
const config = {
  projects: [
    {
      name: 'Desktop Chromium',
      use: {
        browserName: 'chromium',
        // Test against Chrome Beta channel.
        channel: 'chrome-beta',
      },
    },
    {
      name: 'Desktop Safari',
      use: {
        browserName: 'webkit',
        viewport: { width: 1200, height: 750 },
      }
    },
    // Test against mobile viewports.
    {
      name: 'Mobile Chrome',
      use: devices['Pixel 5'],
    },
    {
      name: 'Mobile Safari',
      use: devices['iPhone 12'],
    },
    {
      name: 'Desktop Firefox',
      use: {
        browserName: 'firefox',
        viewport: { width: 800, height: 600 },
      }
    },
  ],
};

module.exports = config;

// playwright.config.ts
import { PlaywrightTestConfig, devices } from '@playwright/test';

const config: PlaywrightTestConfig = {
  projects: [
    {
      name: 'Chrome Stable',
      use: {
        browserName: 'chromium',
        // Test against Chrome Stable channel.
        channel: 'chrome',
      },
    },
    {
      name: 'Desktop Safari',
      use: {
        browserName: 'webkit',
        viewport: { width: 1200, height: 750 },
      }
    },
    // Test against mobile viewports.
    {
      name: 'Mobile Chrome',
      use: devices['Pixel 5'],
    },
    {
      name: 'Mobile Safari',
      use: devices['iPhone 12'],
    },
    {
      name: 'Desktop Firefox',
      use: {
        browserName: 'firefox',
        viewport: { width: 800, height: 600 },
      }
    },
  ],
};
export default config;

Configure NPM script to run tests. Playwright Test will automatically pick up playwright.config.js or playwright.config.ts.

{
  "scripts": {
    "test": "playwright test"
  }
}

If you put your configuration file in a different place, pass it with --config option.

{
  "scripts": {
    "test": "playwright test --config=tests/example.config.js"
  }
}

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