python-testing

# Python Testing Hub Testing standards for pytest configuration, fixture management, and TDD implementation. ## Quick Start 1. **Dependencies**: `pip install pytest pytest-cov pytest-asyncio pytest-mock` 2. **Configuration**: Add the following to `pyproject.toml`: ```toml [tool.pytest.ini_options] testpaths = ["tests"] addopts = "--cov=src" ``` 3. **Verification**: Run `pytest` to confirm discovery of files matching `test_*.py`. ## When To Use - Constructing unit and integration tests for Python 3.9+ projects. - Isolating external dependencies using `pytest-mock` or custom monkeypatching. - Validating asynchronous logic with `pytest-asyncio` markers and event loop management. - Configuring project-wide coverage thresholds and reporting. ## When NOT To Use - Evaluating test quality - use pensive:test-review instead - Infrastructure test config - use leyline:pytest-config ## Modules This skill uses modular loading to manage the system prompt budget. ### Core Implementation - See `modules/unit-testing.md` - AAA (Arrange-Act-Assert) pattern, basic test structure, and exception validation. - See `modules/fixtures-and-mocking.md` - Request-scoped fixtures, parameterization, and boundary mocking. - See `modules/async-testing.md` - Coroutine testing, async fixtures, and concurrency validation. ### Infrastructure & Workflow - See `modules/test-infrastructure.md` - Directory standards, `conftest.py` management, and coverage tools. - See `modules/testing-workflows.md` - Local execution patterns and GitHub Actions integration. ### Standards - See `modules/test-quality.md` - Identification of common anti-patterns like broad exception catching or shared state between tests. ## Exit Criteria - Tests implement the AAA pattern. - Coverage reaches the 80% project minimum. - Individual tests are independent and do not rely on execution order. - Fixtures are scoped appropriately (function, class, or session) to prevent side effects. - Mocking is restricted to external system boundaries. ## Troubleshooting - **Test Discovery**: Verify filenames match the `test_*.py` pattern. Use `pytest --collect-only` to debug discovery paths. - **Import Errors**: Ensure the local source directory is in the path, typically by installing in editable mode with `pip install -e .`. - **Async Failures**: Confirm that `pytest-asyncio` is installed and that async tests use the `@pytest.mark.asyncio` decorator or corresponding auto-mode configuration.