---

name: lint description: Run linting and formatting checks on Ray code

Lint Modified Files

Run pre-commit on the files you changed:

pre-commit run --files $(git diff --name-only HEAD)

pre-commit run without --files only operates on staged files, so pass the modified file list explicitly.

If pre-commit is not installed:

pip install -c python/requirements_compiled.txt pre-commit && pre-commit install

Handling remaining errors

Pre-commit auto-fixes simple issues (formatting, long lines, unused imports). Review any remaining errors — these typically need code changes such as adding a missing import, resolving a name conflict, or restructuring logic. Fix them by editing the source code directly.

Use # noqa only for false positives that cannot be resolved by changing the code, and include the rule code and reason: # noqa: E501 — URL cannot be split.

Exclusions

pyproject.toml lists files in per-file-ignores and extend-exclude. When the PR modifies a file that is on one of these lists, fix the lint issues in your changes and consider removing the file from the list. Leave exclusion entries for files outside the PR scope untouched.

Reference

• Hook config: .pre-commit-config.yaml
• Ruff config: pyproject.toml ([tool.ruff] section)
• Docs: doc/source/ray-contribute/development.md ("Development tooling")