Ruff¶

Ruff is an extremely fast Python linter and code formatter written in Rust that can enforce the rules of flake8, isort, perflint, Black, Bandit, and others. In total, Ruff can check over 800 rules.

Installation¶

$ uv add --dev ruff

Check¶

You can then check the installation with

$ uv run ruff check /PATH/TO/YOUR/SOURCE/FILE

Shell auto-completion¶

Ruff supports autocompletion for most shells. A shell-specific script can be generated with uv run ruff generate-shell-completion SHELL, where SHELL is either bash, elvish, fig, fish, powershell or zsh, for example

Bash

$ ruff generate-shell-completion zsh >> ~/.bash_completion

Zsh

% ruff generate-shell-completion zsh > ~/.zfunc/_ruff

Then, the following lines must be added to your ~/.zshrc file, if they are not already there:

fpath+=~/.zfunc
autoload -Uz compinit && compinit

Oh My Zsh

% mkdir $ZSH_CUSTOM/plugins/ruff
% ruff generate-shell-completion zsh > $ZSH_CUSTOM/plugins/ruff/_ruff

Configuration¶

Unlike Black’s default formatting of 88 characters, I prefer a line length of 79 characters. To do this, you can enter the following in the pyproject.toml file:

[tool.ruff]
line-length = 79

Tip

Usually, we first add all rules to ruff lint before excluding individual ones, for example:

[tool.ruff.lint]
select = ["ALL"]
ignore = [
    "A",       # Shaddowing is fine
]

Ruff also supports monorepos with different rules through hierarchical and cascading configurations.

Integration¶

Jupyter Notebooks¶

Ruff supports linting and formatting Jupyter Notebooks with nbQA. With jupyter-ruff, you can also use Ruff in your notebooks.

IDE¶

Integration with other editors such as Visual Studio Code, PyCharm or Vim is also possible. For the configuration, take a look at Setup.

pre-commit¶

Ruff can be used as a pre-commit hook via ruff-pre-commit:

repos:
  - repo: https://github.com/astral-sh/ruff-pre-commit
    rev: v0.12.10
    hooks:
    - id: ruff-check
      args: [--fix, --exit-non-zero-on-fix]
      exclude: docs
    - id: ruff-format