pytest

Test behavior, not implementation. Tests are executable documentation — if the test name doesn't explain what the code does, rewrite it.

pytest is Python's standard testing framework. It uses plain assert statements, fixtures for setup/teardown, and a rich plugin ecosystem. All patterns target Python 3.14+.

References

• Fixture patterns, scope, factories, teardown — [${CLAUDE_SKILL_DIR}/references/fixtures.md]: Fixture lifecycle, yield fixtures, factory pattern, request object, parametrized fixtures
• Parametrize patterns, indirect, IDs — [${CLAUDE_SKILL_DIR}/references/parametrize.md]: Multi-parameter examples, indirect fixtures, custom IDs, stacking decorators
• Monkeypatch patterns, scoped patches — [${CLAUDE_SKILL_DIR}/references/monkeypatch.md]: API overview, attribute/env/dict patching, scoped monkeypatch, common recipes
• Plugin ecosystem and configuration — [${CLAUDE_SKILL_DIR}/references/plugins.md]: pytest-asyncio, pytest-mock, pytest-xdist, pytest-cov configuration patterns