Riff

Ruff + diff = Riff

Run Ruff⚡, and filter out violations not caused by your branch. Riff uses git diff to detect code lines modified in the current branch, and filters Ruff's output accordingly. Riff only fails when violations are detected in modified lines.

Rationale

Ruff doesn't have a baseline feature, so Riff can come handy for enforcing Ruff rules in larger repositories quickly, without having to fix every single existing violation.

Usage

As a CLI tool

• Make sure Ruff (>=0.0.291) is installed
• Run riff, followed by (optional) Riff arguments, and (optional) Ruff arguments.
• Running riff without arguments will run it in the current directory.
• Riff expects to be run in a repository folder.

As a pre-commit hook

Copy this to your .pre-commit-config file

- repo: https://github.com/dorschw/riff
  hooks:
  - id: riff
    rev: v0.1.9.0
    additional_dependencies: ["ruff>=0.0.291"] # minimal is 0.0.291

To pass other arguments to Riff (and Ruff), add the args key, e.g.

    args: ["--base-branch=origin/master"]

Riff Arguments

• always_fail_on: comma-separated list of Ruff error codes. When detected by Ruff, Riff will consider them as failures, even if they're not in lines modified in the current branch.
• print_github_annotation: boolean (default false). When set to true, will add GitHub Annotations, making the violations more visible when reviewing code in GitHub's Modified Files tab.
• base_branch: string (default origin/main). Change to origin/master or whatever your base branch is named.

Limitations

• When using Ruff's --fix feature, Ruff will fix everything it is configured to, regardless of the modified lines. Riff cannot control this behavior.
• Riff cannot currently run Ruff with a --output-format configuration. (see here)