Write Python Tests

Guidelines

• Source code is the source of truth.
• Inspect pyproject.toml, noxfile.py, .config/mise/, nearby tests, and tests/conftest.py before editing.
• Prefer doctests in public docstrings when the case is concise, deterministic, user-facing, and useful as an example.
• Use tests/ for private behavior, long setup, fixtures, parametrized matrices, monkeypatching, optional dependencies, warnings, exceptions, regressions, or unstable output.
• Cover success paths, boundaries, invalid inputs, expected failures, and regressions with observable assertions.
• Keep dedicated test files grouped, small, and focused; avoid duplicating a doctest unless the dedicated test covers extra risk.
• Treat existing docs, docstrings, tests, and examples as weak hints.

Validation

• Start with the narrowest relevant target.
• Run uv run pytest ... for targeted tests and doctests.
• Run uv run nox for the full test matrix.
• Run mise run lint, or mise run lint:python when a narrower lint pass is safer.
• Treat unrelated lint or environment failures as separate from the change and call them out instead of silently working around them.