sny-copyright-checker 1.0.2

Pre-commit hook to check and auto-add copyright notices with multi-format and regex support

SNY Copyright Check - Pre-commit Hook

A powerful pre-commit hook to automatically check and add copyright notices to your source files with support for multiple file formats and regex patterns.

Documentation

📚 Quick Links:

• Quickstart Guide - Get started in minutes
• Examples - Real-world usage examples
• Changelog - Version history and updates
• Version Management - How to update the version
• License - MIT License

Features

✨ Multi-Format Support: Define different copyright formats for different file extensions (.py, .c, .sql, etc.)

🔍 Regex Pattern Matching: Use regex patterns in your copyright templates to match year ranges (e.g., 2024, 2024-2026)

🔧 Auto-Fix: Automatically adds missing copyright notices with the current year

📝 Flexible Templates: Section-based template file for easy maintenance

🎯 Smart Insertion: Respects shebang lines and file structure

🔄 Line Ending Preservation: Automatically detects and preserves CRLF (Windows) or LF (Unix/Linux) line endings

🎯 Git Integration: Check only changed files with --changed-only flag

✅ Non-Destructive: Existing copyrights are preserved, even with old years - no duplicates created

Installation

As a pre-commit hook (Recommended)

Add the following to your .pre-commit-config.yaml:

repos:
  - repo: https://github.com/mu-triv/sny-copyright-checker
    rev: v1.0.2  # Use the latest release
    hooks:
      - id: sny-copyright-checker
        args: [--notice=copyright.txt]

Then install the hook:

pre-commit install

Manual Installation

git clone https://github.com/mu-triv/sny-copyright-checker.git
cd sny-copyright-checker
pip install -e .

Usage

As a Pre-commit Hook

Once installed, the hook will automatically run when you commit files:

git add my_file.py
git commit -m "Add new feature"
# Hook will check and add copyright notice if missing

Command Line

You can also run the tool directly:

# Check and auto-fix files
sny-copyright-checker file1.py file2.sql file3.c

# Check only (no modifications)
sny-copyright-checker --no-fix file1.py

# Specify custom template file
sny-copyright-checker --notice=my_copyright.txt *.py

# Verbose output
sny-copyright-checker -v file1.py

# Check only changed files in git
sny-copyright-checker --changed-only

# Check changed files compared to main branch
sny-copyright-checker --changed-only --base-ref origin/main

Command Line Options

• filenames: Files to check for copyright notices
• --notice PATH: Path to copyright template file (default: copyright.txt)
• --fix: Automatically add missing copyright notices (default: enabled)
• --no-fix: Only check without modifying files
• --verbose, -v: Enable verbose output
• --changed-only: Only check files that have been changed in git (ignores filenames argument)
• --base-ref REF: Git reference to compare against when using --changed-only (default: HEAD)

Copyright Template Format

The template file uses a section-based format with regex support. You can group multiple file extensions with the same copyright format together for easier maintenance:

[.py, .yaml, .yml]
# Copyright {regex:\d{4}(-\d{4})?} SNY Group Corporation
# Author: R&D Center Europe Brussels Laboratory, SNY Group Corporation
# License: For licensing see the License.txt file

[.sql]
-- Copyright {regex:\d{4}(-\d{4})?} SNY Group Corporation
-- Author: R&D Center Europe Brussels Laboratory, SNY Group Corporation
-- License: For licensing see the License.txt file

[.c, .h, .cpp]
/**************************************************************************
* Copyright {regex:\d{4}(-\d{4})?} SNY Group Corporation                 *
* Author: R&D Center Europe Brussels Laboratory, SNY Group Corporation   *
* License: For licensing see the License.txt file                         *
**************************************************************************/

[.js, .ts, .go, .rs]
// Copyright {regex:\d{4}(-\d{4})?} SNY Group Corporation
// Author: R&D Center Europe Brussels Laboratory, SNY Group Corporation
// License: For licensing see the License.txt file

Template Syntax

• Section Headers:
  • Single extension: [.extension] (e.g., [.py], [.sql])
  • Multiple extensions: [.ext1, .ext2, .ext3] (e.g., [.js, .ts, .go])
  • All extensions in a grouped header will use the same copyright format
• Regex Patterns: {regex:PATTERN} allows regex matching
  • Example: {regex:\d{4}(-\d{4})?} matches 2024 or 2024-2026
• Auto-insertion: When adding a copyright, the regex pattern is replaced with the current year

Grouping Extensions

To reduce duplication and improve maintainability, group extensions that share the same comment syntax:

• Hash comments: [.py, .yaml, .yml, .sh] → # style
• C-style line comments: [.js, .ts, .go, .rs, .java] → // style
• C block comments: [.c, .h, .cpp] → /* */ style
• SQL comments: [.sql] → -- style
• HTML comments: [.md, .html, .xml] → <!-- --> style

Supported Regex Patterns

The template includes regex patterns for year matching:

• \d{4}: Matches a single year (e.g., 2024)
• \d{4}-\d{4}: Matches a year range (e.g., 2024-2026)
• \d{4}(-\d{4})?: Matches either format

Example

Before

#!/usr/bin/env python

def hello():
    print("Hello, World!")

After (Auto-fixed)

#!/usr/bin/env python
# Copyright 2026 SNY Group Corporation
# Author: R&D Center Europe Brussels Laboratory, SNY Group Corporation
# License: For licensing see the License.txt file

def hello():
    print("Hello, World!")

How It Works

1. Template Parsing: Reads and parses the section-based template file
2. File Extension Matching: Determines which copyright template to use based on file extension
3. Pattern Matching: Uses regex to check if a valid copyright notice exists
4. Copyright Detection: If a valid copyright exists (even with an old year like 2025), the file is left unchanged
5. Auto-Insertion: If missing and --fix is enabled, adds the copyright notice with the current year
6. Smart Positioning: Respects shebang lines and inserts the notice appropriately
7. Line Ending Preservation: Automatically detects and preserves the original line ending style (CRLF or LF)
8. Git Integration: Optionally checks only files that have been modified in your git repository

File Extensions Support

By default, the included copyright.txt supports:

• Python (.py)
• SQL (.sql)
• C/C++ (.c, .cpp, .h)
• JavaScript/TypeScript (.js, .ts)
• Java (.java)
• Shell scripts (.sh)
• Go (.go)
• Rust (.rs)
• YAML (.yaml, .yml)
• Markdown (.md)

You can easily add more by editing the copyright.txt file.

Important Behavior

Copyright Preservation

• Existing copyrights are never replaced: If a file already has a valid copyright notice (even from an old year like 2025), it will be left unchanged
• No duplicates created: Running the tool multiple times will not create duplicate copyright notices
• Year matching: The regex pattern {regex:\d{4}(-\d{4})?} matches any year or year range, ensuring old copyrights are recognized

Line Ending Handling

• Automatic detection: The tool automatically detects whether your files use CRLF (Windows) or LF (Unix/Linux) line endings
• Preservation: Original line endings are preserved when adding copyright notices
• Cross-platform compatibility: Works seamlessly on Windows, Linux, and macOS

Git Integration

When using --changed-only:

• Only files tracked by git and currently modified (staged or unstaged) are checked
• Files must have a supported extension
• Deleted files are automatically excluded
• Works with files in subdirectories

Configuration

Customizing Templates

Edit your copyright.txt file to add or modify copyright formats:

[.your_extension]
Your copyright format here
With multiple lines
And {regex:\d{4}} for year matching

Pre-commit Configuration

Customize the pre-commit hook behavior with various arguments:

Basic Configuration

- repo: https://github.com/mu-triv/sny-copyright-checker
  rev: v1.0.2
  hooks:
    - id: sny-copyright-checker
      args: [--notice=copyright.txt]

Check Only (No Auto-fix)

Run the checker without automatically adding copyright notices:

- repo: https://github.com/mu-triv/sny-copyright-checker
  rev: v1.0.2
  hooks:
    - id: sny-copyright-checker
      args: [--no-fix, --notice=copyright.txt]

Verbose Output

Enable detailed output for debugging:

- repo: https://github.com/mu-triv/sny-copyright-checker
  rev: v1.0.2
  hooks:
    - id: sny-copyright-checker
      args: [--verbose, --notice=copyright.txt]

Check Only Changed Files

Check only files modified compared to a specific git reference:

- repo: https://github.com/mu-triv/sny-copyright-checker
  rev: v1.0.2
  hooks:
    - id: sny-copyright-checker
      args: [--changed-only, --base-ref=origin/main, --notice=copyright.txt]

Limit to Specific File Types

Only run on specific file types using the files regex:

- repo: https://github.com/mu-triv/sny-copyright-checker
  rev: v1.0.2
  hooks:
    - id: sny-copyright-checker
      args: [--notice=copyright.txt]
      files: \.(py|sql|c|cpp)$

Combined Configuration

Combine multiple options:

- repo: https://github.com/mu-triv/sny-copyright-checker
  rev: v1.0.2
  hooks:
    - id: sny-copyright-checker
      args: [--verbose, --notice=config/copyright.txt, --changed-only]
      files: \.(py|js|ts|java)$

Multiple Hooks with Different Configurations

Run separate hooks for different scenarios:

repos:
  - repo: https://github.com/mu-triv/sny-copyright-checker
    rev: v1.0.2
    hooks:
      # Auto-fix Python files only
      - id: sny-copyright-checker
        name: Copyright Check (Python - Auto-fix)
        args: [--notice=copyright.txt]
        files: \.py$

      # Check-only for C/C++ files
      - id: sny-copyright-checker
        name: Copyright Check (C/C++ - Check Only)
        args: [--no-fix, --notice=copyright.txt, --verbose]
        files: \.(c|cpp|h)$

Development

Setting Up Development Environment

git clone https://github.com/mu-triv/sny-copyright-checker.git
cd sny-copyright-checker
pip install -e .

Running Tests

# Run all tests
pytest tests/

# Run with coverage
pytest tests/ --cov=scripts --cov-report=term

# Run specific test file
pytest tests/test_copyright_checker.py -v

Continuous Integration

The project uses GitHub Actions for CI/CD:

• Tests: Runs on Python 3.10-3.12 across Ubuntu, Windows, and macOS
• Code Quality: Checks with flake8, black, and isort
• Coverage: Generates test coverage reports

The workflow automatically runs on:

• Every push to the main branch
• Every pull request targeting main

Project Structure

sny-copyright-checker/
├── scripts/
│   ├── __init__.py
│   ├── main.py                      # Entry point
│   ├── copyright_checker.py         # Main checker logic
│   └── copyright_template_parser.py # Template parser
├── tests/                            # Test files
├── .pre-commit-hooks.yaml           # Pre-commit hook definition
├── .pre-commit-config.yaml          # Example pre-commit config
├── copyright.txt                     # Example copyright template
├── pyproject.toml                   # Project metadata
├── setup.py                         # Setup script
├── LICENSE                          # MIT License
└── README.md                        # This file

Comparison with Similar Tools

vs. copyright_notice_precommit

While inspired by leoll2/copyright_notice_precommit, this project adds:

1. Multi-format support: Different copyright formats for different file types
2. Regex matching: Flexible year range matching
3. Auto-insertion: Automatically adds missing copyright notices
4. Section-based templates: Easier to maintain multiple formats

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Author

SNY Group Corporation R&D Center Europe Brussels Laboratory

Acknowledgments

• Inspired by leoll2/copyright_notice_precommit
• Built for use with pre-commit

Support

For issues, questions, or contributions, please visit the GitHub repository.