Chapter 3: Configuration Files and Custom Rules

Knowledge Points

Configuration File Priority

Pylint searches for configuration files in the following order:

1. Command line arguments - Highest priority
2. .pylintrc in current directory
3. .pylintrc in user home directory
4. pylintrc in project root directory
5. System configuration file

Configuration File Format

Pylint configuration files use INI format, containing multiple sections:

graph TD
    A[.pylintrc Configuration File] --> B[MASTER Main Settings]
    A --> C[MESSAGES CONTROL Message Control]
    A --> D[REPORTS Report Settings]
    A --> E[REFACTORING Refactoring Settings]
    A --> F[BASIC Basic Checks]
    A --> G[FORMAT Format Checks]
    A --> H[LOGGING Logging Checks]
    A --> I[MISCELLANEOUS Other Settings]
    A --> J[SIMILARITIES Similarity Checks]
    A --> K[SPELLING Spelling Checks]
    A --> L[TYPECHECK Type Checks]
    A --> M[VARIABLES Variable Checks]
    A --> N[CLASSES Class Checks]
    A --> O[DESIGN Design Checks]
    A --> P[IMPORTS Import Checks]
    A --> Q[EXCEPTIONS Exception Checks]

Sample Code

Generation and Basic Configuration

The .pylintrc configuration file controls how Pylint analyzes your code. You can generate a default configuration file and customize it for your project needs. The configuration uses INI format with sections for different check categories.

Project-Specific Configuration Examples

Different types of projects require different Pylint configurations. Web projects, data science projects, and library projects each have unique requirements for code quality checks and naming conventions.

Custom Rules and Management

Projects can define custom rules to match specific coding standards. This includes disabling checks for test files, configuration files, and special-purpose modules while maintaining strict checks for production code.

Team Configuration Management

Team-level configuration management ensures consistency across all team members. Using version-controlled configuration files and automated compliance checking helps maintain code quality standards.

Configuration File Debugging and Optimization

Configuration files should be validated for syntax errors and tested for effectiveness. Performance analysis helps identify if certain configurations slow down the linting process.

Configuration files are the core of Pylint’s flexibility. Proper configuration can make the tool better adapt to project requirements and improve development efficiency.