python-quality-gate

Use this skill when:

• You changed Python code and want it to pass formatting/lint/type/tests.
• You're preparing a PR/release and need a consistent "done" checklist.

Steps

1. Locate project tooling config

• Check for pyproject.toml, ruff.toml, setup.cfg, mypy.ini, pytest.ini.
• Follow repo config over default tool flags.

2. Format

• Run: python -m black .
• If Black isn't installed, propose adding it to the dev environment and explain how to install.

3. Lint

• Run: python -m ruff check . --fix
• If Ruff isn't installed, propose adding it and re-run.

4. Types (only if configured/expected)

• If mypy.ini or mypy config exists, run: python -m mypy .
• Fix type errors by improving annotations (avoid weakening to Any unless unavoidable).

5. Tests

• Run: python -m pytest -q
• If failures: fix implementation first; only adjust tests if the test is wrong or spec changed.

6. Exit criteria

• No formatting diffs from Black.
• Ruff clean (or only allowed ignores).
• Mypy clean (if used).
• Pytest passing.

Common fixes

• Replace == None with is None.
• Prefer Pathlib over manual path string ops when appropriate.
• Tighten return types and avoid ambiguous Optional behavior.