# Ruff — Ultra-Fast Python Linter & Formatter

> Python linter and formatter written in Rust. 10-100x faster than Flake8 and Black. Replaces Flake8, isort, pyupgrade, and more with a single tool. 40,000+ GitHub stars.

## Install

Save as a script file and run:

## Quick Use

```bash
# Install
pip install ruff

# Lint your project
ruff check .

# Auto-fix issues
ruff check --fix .

# Format code (replaces Black)
ruff format .
```

Add to `pyproject.toml`:
```toml
[tool.ruff]
line-length = 88
target-version = "py312"

[tool.ruff.lint]
select = ["E", "F", "I", "N", "UP", "B", "SIM"]
```

---

## Intro

Ruff is an extremely fast Python linter and code formatter written in Rust with 40,000+ GitHub stars. It replaces Flake8, Black, isort, pyupgrade, pydocstyle, and autoflake with a single tool that runs 10-100x faster. A full lint pass on CPython (600K+ lines) completes in under 0.3 seconds. Best for Python developers and AI agents who need instant feedback on code quality. Works with: any Python project, CI/CD pipelines, pre-commit hooks. Setup time: under 1 minute.

---

## What Ruff Replaces

| Old Tool | Ruff Equivalent | Speed Improvement |
|----------|----------------|-------------------|
| Flake8 | `ruff check` | 25-100x faster |
| Black | `ruff format` | 10-30x faster |
| isort | `ruff check --select I` | 50x faster |
| pyupgrade | `ruff check --select UP` | 100x faster |
| pydocstyle | `ruff check --select D` | 50x faster |
| autoflake | `ruff check --select F` | 80x faster |

### 800+ Lint Rules
Ruff implements rules from 50+ Flake8 plugins:

```toml
[tool.ruff.lint]
select = [
    "E",    # pycodestyle errors
    "F",    # pyflakes
    "I",    # isort
    "N",    # pep8-naming
    "UP",   # pyupgrade
    "B",    # bugbear
    "SIM",  # simplify
    "TCH",  # type-checking imports
    "RUF",  # ruff-specific rules
]
```

### Auto-Fix
Most issues can be fixed automatically:

```bash
ruff check --fix .
# Fixed 42 issues:
#   12 × F401 (unused imports removed)
#   8  × I001 (imports sorted)
#   6  × UP035 (deprecated typing replaced)
#   ...
```

### Editor Integration
- VS Code: `charliermarsh.ruff` extension
- Neovim: built-in LSP support
- Pre-commit: `ruff-pre-commit` hook

### CI Configuration

```yaml
# .github/workflows/lint.yml
- name: Ruff
  run: |
    pip install ruff
    ruff check .
    ruff format --check .
```

### Key Stats
- 40,000+ GitHub stars
- 800+ lint rules from 50+ plugins
- 10-100x faster than alternatives
- Written in Rust by Astral
- Used by FastAPI, Pandas, Airflow

### FAQ

**Q: What is Ruff?**
A: Ruff is a Python linter and formatter written in Rust that replaces Flake8, Black, isort, and several other tools with a single, 10-100x faster alternative.

**Q: Is Ruff free?**
A: Yes, fully open-source under MIT license.

**Q: Is Ruff compatible with Black formatting?**
A: Yes, `ruff format` is designed as a drop-in replacement for Black with near-identical output.

---

## Source & Thanks

> Created by [Astral](https://github.com/astral-sh). Licensed under MIT.
>
> [ruff](https://github.com/astral-sh/ruff) — ⭐ 40,000+

Thanks to the Astral team for making Python linting instant.

---

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## 快速使用

```bash
pip install ruff
ruff check .        # 代码检查
ruff check --fix .  # 自动修复
ruff format .       # 代码格式化
```

---

## 简介

Ruff 是一个用 Rust 编写的超快 Python 代码检查和格式化工具，GitHub 40,000+ stars。单一工具替代 Flake8、Black、isort 等 6 个工具，速度快 10-100 倍。CPython 60 万行代码的完整检查在 0.3 秒内完成。适合需要即时代码质量反馈的 Python 开发者和 AI Agent。

---

## 来源与感谢

> Created by [Astral](https://github.com/astral-sh). Licensed under MIT.
>
> [ruff](https://github.com/astral-sh/ruff) — ⭐ 40,000+

---
Source: https://tokrepo.com/en/workflows/456bad98-6764-4441-8f63-457b7c3ed3dd
Author: Script Depot