pylint

Project Overview

Pylint is a static code analyzer for Python that analyzes source without executing it, checking for errors, enforcing coding standards, finding code smells, and suggesting refactoring. Built on its internal code representation astroid, it infers actual values and finds more issues even in code without complete type annotations. Pylint is highly configurable, supports plugins for custom checks, and ships with pyreverse for class diagrams and symilar for duplicate code detection.

A deep checker that finds errors and smells without running your code.

Key Features

• Error checking: finds potential errors without running the code
• Standards enforcement: enforces team coding standards
• Smell detection: identifies code smells like duplication and long functions
• Type inference: infers actual values via astroid even without full type annotations
• Refactoring advice: offers actionable improvement suggestions
• Plugin ecosystem: supports custom plugins plus ready-made ones like pylint-django
• Bundled tools: includes pyreverse for diagrams and symilar for duplicate code
• Highly configurable: individual checks can be enabled or disabled

Target Audience

• Python developers
• Legacy project maintainers
• Code quality owners
• Open-source maintainers
• Teams needing deep static analysis

Quick Start

1. Install Pylint

pip install pylint

2. Check a file or project

pylint mymodule.py

3. For legacy projects start with errors only

pylint --errors-only mymodule.py

4. Gradually enable more check categories in configuration as priorities evolve

Core Advantages

• Strong inference: finds deep issues without requiring complete type annotations
• More thorough: covers more checks than most linters
• Extensible: plugin mechanism supports custom checks for internal libraries

System Requirements

Notes

• Gradual adoption: start legacy projects with --errors-only, then widen the checks
• Speed tradeoff: deep inference is slower; complement with fast tools like ruff
• Third-party libs: some libraries need matching pylint plugins for full support