playwright/docs/src/test-runners-python.md

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---
id: test-runners
title: "Pytest Plugin Reference"
---
## Introduction
Playwright provides a [Pytest](https://docs.pytest.org/en/stable/) plugin to write end-to-end tests. To get started with it, refer to the [getting started guide](./intro.md).
## Usage
To run your tests, use [Pytest](https://docs.pytest.org/en/stable/) CLI.
```bash
pytest --browser webkit --headed
```
If you want to add the CLI arguments automatically without specifying them, you can use the [pytest.ini](https://docs.pytest.org/en/stable/reference.html#ini-options-ref) file:
```ini
# content of pytest.ini
[pytest]
# Run firefox with UI
addopts = --headed --browser firefox
```
## CLI arguments
Note that CLI arguments are only applied to the default `browser`, `context` and `page` fixtures.
If you create a browser, a context or a page with the API call like [`method: Browser.newContext`], the CLI arguments are not applied.
- `--headed`: Run tests in headed mode (default: headless).
- `--browser`: Run tests in a different browser `chromium`, `firefox`, or `webkit`. It can be specified multiple times (default: `chromium`).
- `--browser-channel` [Browser channel](./browsers.md) to be used.
- `--slowmo` Slows down Playwright operations by the specified amount of milliseconds. Useful so that you can see what is going on (default: 0).
- `--device` [Device](./emulation.md) to be emulated.
- `--output` Directory for artifacts produced by tests (default: `test-results`).
- `--tracing` Whether to record a [trace](./trace-viewer.md) for each test. `on`, `off`, or `retain-on-failure` (default: `off`).
- `--video` Whether to record video for each test. `on`, `off`, or `retain-on-failure` (default: `off`).
- `--screenshot` Whether to automatically capture a screenshot after each test. `on`, `off`, or `only-on-failure` (default: `off`).
- `--full-page-screenshot` Whether to take a full page screenshot on failure. By default, only the viewport is captured. Requires `--screenshot` to be enabled (default: `off`).
## Fixtures
This plugin configures Playwright-specific [fixtures for pytest](https://docs.pytest.org/en/latest/fixture.html). To use these fixtures, use the fixture name as an argument to the test function.
```py
def test_my_app_is_working(fixture_name):
pass
# Test using fixture_name
# ...
```
**Function scope**: These fixtures are created when requested in a test function and destroyed when the test ends.
- `context`: New [browser context](./browser-contexts) for a test.
- `page`: New [browser page](./pages) for a test.
- `new_context`: Allows creating different [browser contexts](./browser-contexts) for a test. Useful for multi-user scenarios. Accepts the same parameters as [`method: Browser.newContext`].
**Session scope**: These fixtures are created when requested in a test function and destroyed when all tests end.
- `playwright`: [Playwright](./api/class-playwright) instance.
- `browser_type`: [BrowserType](./api/class-browsertype) instance of the current browser.
- `browser`: [Browser](./api/class-browser) instance launched by Playwright.
- `browser_name`: Browser name as string.
- `browser_channel`: Browser channel as string.
- `is_chromium`, `is_webkit`, `is_firefox`: Booleans for the respective browser types.
**Customizing fixture options**: For `browser` and `context` fixtures, use the following fixtures to define custom launch options.
- `browser_type_launch_args`: Override launch arguments for [`method: BrowserType.launch`]. It should return a Dict.
- `browser_context_args`: Override the options for [`method: Browser.newContext`]. It should return a Dict.
Its also possible to override the context options ([`method: Browser.newContext`]) for a single test by using the `browser_context_args` marker:
```python
import pytest
@pytest.mark.browser_context_args(timezone_id="Europe/Berlin", locale="en-GB")
def test_browser_context_args(page):
assert page.evaluate("window.navigator.userAgent") == "Europe/Berlin"
assert page.evaluate("window.navigator.languages") == ["de-DE"]
```
## Parallelism: Running Multiple Tests at Once
If your tests are running on a machine with a lot of CPUs, you can speed up the overall execution time of your test suite by using [`pytest-xdist`](https://pypi.org/project/pytest-xdist/) to run multiple tests at once:
```bash
# install dependency
pip install pytest-xdist
# use the --numprocesses flag
pytest --numprocesses auto
```
Depending on the hardware and nature of your tests, you can set `numprocesses` to be anywhere from `2` to the number of CPUs on the machine. If set too high, you may notice unexpected behavior.
See [Running Tests](./running-tests.md) for general information on `pytest` options.
## Examples
### Configure typings for auto-completion
```py title="test_my_application.py"
from playwright.sync_api import Page
def test_visit_admin_dashboard(page: Page):
page.goto("/admin")
# ...
```
If you're using VSCode with Pylance, these types can be inferred by enabling the `python.testing.pytestEnabled` setting so you don't need the type annotation.
### Using multiple contexts
In order to simulate multiple users, you can create multiple [`BrowserContext`](./browser-contexts) instances.
```py title="test_my_application.py"
from playwright.sync_api import Page, BrowserContext
from pytest_playwright.pytest_playwright import CreateContextCallback
def test_foo(page: Page, new_context: CreateContextCallback) -> None:
page.goto("https://example.com")
context = new_context()
page2 = context.new_page()
# page and page2 are in different contexts
```
### Skip test by browser
```py title="test_my_application.py"
import pytest
@pytest.mark.skip_browser("firefox")
def test_visit_example(page):
page.goto("https://example.com")
# ...
```
### Run on a specific browser
```py title="conftest.py"
import pytest
@pytest.mark.only_browser("chromium")
def test_visit_example(page):
page.goto("https://example.com")
# ...
```
### Run with a custom browser channel like Google Chrome or Microsoft Edge
```bash
pytest --browser-channel chrome
```
```python title="test_my_application.py"
def test_example(page):
page.goto("https://example.com")
```
### Configure base-url
Start Pytest with the `base-url` argument. The [`pytest-base-url`](https://github.com/pytest-dev/pytest-base-url) plugin is used
for that which allows you to set the base url from the config, CLI arg or as a fixture.
```bash
pytest --base-url http://localhost:8080
```
```py title="test_my_application.py"
def test_visit_example(page):
page.goto("/admin")
# -> Will result in http://localhost:8080/admin
```
### Ignore HTTPS errors
```py title="conftest.py"
import pytest
@pytest.fixture(scope="session")
def browser_context_args(browser_context_args):
return {
**browser_context_args,
"ignore_https_errors": True
}
```
### Use custom viewport size
```py title="conftest.py"
import pytest
@pytest.fixture(scope="session")
def browser_context_args(browser_context_args):
return {
**browser_context_args,
"viewport": {
"width": 1920,
"height": 1080,
}
}
```
### Device emulation / BrowserContext option overrides
```py title="conftest.py"
import pytest
@pytest.fixture(scope="session")
def browser_context_args(browser_context_args, playwright):
iphone_11 = playwright.devices['iPhone 11 Pro']
return {
**browser_context_args,
**iphone_11,
}
```
Or via the CLI `--device="iPhone 11 Pro"`
### Using with `unittest.TestCase`
See the following example for using it with `unittest.TestCase`. This has a limitation,
that only a single browser can be specified and no matrix of multiple browsers gets
generated when specifying multiple.
```py
import pytest
import unittest
from playwright.sync_api import Page
class MyTest(unittest.TestCase):
@pytest.fixture(autouse=True)
def setup(self, page: Page):
self.page = page
def test_foobar(self):
self.page.goto("https://microsoft.com")
self.page.locator("#foobar").click()
assert self.page.evaluate("1 + 1") == 2
```
## Debugging
### Use with pdb
Use the `breakpoint()` statement in your test code to pause execution and get a [pdb](https://docs.python.org/3/library/pdb.html) REPL.
```py
def test_bing_is_working(page):
page.goto("https://bing.com")
breakpoint()
# ...
```
## Deploy to CI
See the [guides for CI providers](./ci.md) to deploy your tests to CI/CD.
## Async Fixtures
If you want to use async fixtures, you can use the [`pytest-playwright-asyncio`](https://pypi.org/project/pytest-playwright-asyncio/) plugin.
Make sure to use `pytest-asyncio>=0.24.0` and make your tests use of [`loop_scope=session`](https://pytest-asyncio.readthedocs.io/en/latest/how-to-guides/run_session_tests_in_same_loop.html).
```python
import pytest
from playwright.async_api import Page
@pytest.mark.asyncio(loop_scope="session")
async def test_foo(page: Page):
await page.goto("https://github.com")
# ...
```