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

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---
id: test-runners
title: "Pytest plugin"
---
Write end-to-end tests for your web apps with [Pytest](https://docs.pytest.org/en/stable/).
<!-- TOC -->
## Usage
```bash
pip install pytest-playwright
```
Use the `page` fixture to write a basic test. See [more examples](#examples).
```py
# test_my_application.py
def test_example_is_working(page):
page.goto("https://example.com")
assert page.inner_text('h1') == 'Example Domain'
page.click("text=More information")
```
To run your tests, use pytest CLI.
```bash
# Run tests (Chromium and headless by default)
pytest
# Run tests in headed mode
pytest --headed
# Run tests in a different browser (chromium, firefox, webkit)
pytest --browser firefox
# Run tests in multiple browsers
pytest --browser chromium --browser webkit
```
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
- `--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: all browsers).
- `--browser-channel` [Browser channel](./browsers.md) to be used.
- `--slowmo` Run tests with slow mo.
- `--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`).
## 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):
# 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](https://playwright.dev/python/docs/browser-contexts) for a test.
- `page`: New [browser page](https://playwright.dev/python/docs/pages) for a test.
**Session scope**: These fixtures are created when requested in a test function and destroyed when all tests end.
- `playwright`: [Playwright](https://playwright.dev/python/docs/api/class-playwright) instance.
- `browser_type`: [BrowserType](https://playwright.dev/python/docs/api/class-browsertype) instance of the current browser.
- `browser`: [Browser](https://playwright.dev/python/docs/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 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.
## Examples
### Configure Mypy typings for auto-completion
```py
# test_my_application.py
from playwright.sync_api import Page
def test_visit_admin_dashboard(page: Page):
page.goto("/admin")
# ...
```
### Configure slow mo
Run tests with slow mo with the `--slowmo` argument.
```bash
pytest --slowmo 100
```
### Skip test by browser
```py
# 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
# 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
# test_my_application.py
def test_example(page):
page.goto("https://example.com")
```
### Configure base-url
Start Pytest with the `base-url` argument.
```bash
pytest --base-url http://localhost:8080
```
```py
# test_my_application.py
def test_visit_example(page):
page.goto("/admin")
# -> Will result in http://localhost:8080/admin
```
### Ignore HTTPS errors
```py
# 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
# 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
```py
# 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"`
### Persistent context
```py
# conftest.py
import pytest
from playwright.sync_api import BrowserType
from typing import Dict
@pytest.fixture(scope="session")
def context(
browser_type: BrowserType,
browser_type_launch_args: Dict,
browser_context_args: Dict
):
context = browser_type.launch_persistent_context("./foobar", **{
**browser_type_launch_args,
**browser_context_args,
"locale": "de-DE",
})
yield context
context.close()
```
When using that all pages inside your test are created from the persistent context.
### 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.click("#foobar")
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.