pytest -k: Select Tests by Name Command Reference

Run only the tests whose names match an expression.

pytest -k filters collected tests by a Python-like expression matched against test names and their path. It is the quickest way to run a focused subset in CI.

Common flags / usage

• -k "auth" -- run tests whose name contains auth
• -k "auth and not slow" -- combine with and/or/not
• -k "login or signup" -- match either substring
• pair with --collect-only -- preview what the expression selects

Example

# Fast smoke subset on every push:
- run: python -m pytest -k "smoke and not integration" -q

In CI

Use -k to split a slow suite into fast feedback (a name-matched smoke subset on each push) and a full run on a schedule. The expression matches the test name and the module path, so name conventions make selection predictable.

Key takeaways

• pytest -k selects tests by a name expression with and/or/not.
• It matches against test names and their module path.
• Use it to carve a fast smoke subset out of a larger suite.

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