Running tests
You can run a single test, a set of tests or all tests. Tests can be run on one browser or multiple browsers by using the --browser flag. By default tests are run in a headless manner meaning no browser window will be opened while running the tests and results will be seen in the terminal. If you prefer you can run your tests in headed mode by using the --headed CLI argument.
You will learn
Command Line
To run your tests use the pytest command. This will run your tests on the Chromium browser by default. Tests run in headless mode by default meaning no browser window will be opened while running the tests and results will be seen in the terminal.
pytest
Running tests headed
To run your tests in headed mode use the --headed flag. This will open up a browser window while running your tests.
pytest --headed
Running tests on different browsers
To specify which browser you would like to run your tests on use the --browser flag followed by the name of the browser.
pytest --browser webkit
To specify multiple browsers to run your tests on use the --browser flag multiple times followed by the name of each browser.
pytest --browser webkit --browser firefox
Running specific tests
To run a single test file pass in the name of the test file that you want to run.
pytest test_login.py
To run a set of test files pass in the names of the test files that you want to run.
pytest tests/test_todo_page.py tests/test_landing_page.py
To run a specific test pass in the function name of the test you want to run.
pytest -k test_add_a_todo_item
Run tests in Parallel
To run your tests in parallel use the --numprocesses flag followed by the number of processes you would like to run your tests on. We recommend half of logical CPU cores.
pytest --numprocesses 2
(This assumes pytest-xdist is installed. For more information see here.)
For more information see Playwright Pytest usage or the Pytest documentation for general CLI usage.
Debugging Tests
Since Playwright runs in Python, you can debug it with your debugger of choice with e.g. the Python extension in Visual Studio Code. Playwright comes with the Playwright Inspector which allows you to step through Playwright API calls, see their debug logs and explore locators.
- Bash
- PowerShell
- Batch
PWDEBUG=1 pytest -s
$env:PWDEBUG=1
pytest -s
set PWDEBUG=1
pytest -s
Check out our debugging guide to learn more about the Playwright Inspector as well as debugging with Browser Developer tools.