feat: Add complete Python testing infrastructure with Poetry

[llbbl]

Add Python Testing Infrastructure

Summary

This PR sets up a comprehensive testing infrastructure for the cs-books repository using Poetry as the package manager and pytest as the testing framework. The setup provides a ready-to-use testing environment where developers can immediately start writing tests for the existing Python scripts.

Changes Made

Package Management

• Poetry Configuration: Created pyproject.toml with Poetry as the package manager
• Dependencies: Added testing dependencies as development requirements:
  • pytest (^7.4.0) - Main testing framework
  • pytest-cov (^4.1.0) - Coverage reporting
  • pytest-mock (^3.11.0) - Mocking utilities
• Existing Dependencies: Migrated PyGithub dependency from implicit imports

Testing Configuration

• pytest Settings: Configured comprehensive pytest options including:
  • Strict markers and configuration
  • Coverage reporting with HTML and XML output formats
  • Test discovery patterns for test_*.py and *_test.py files
  • Custom markers: unit, integration, and slow
• Coverage Settings:
  • Source directories: src, add_commit_git_push, update_readme
  • Exclusions for test files and common patterns
  • Multiple report formats (terminal, HTML, XML)
  • Coverage threshold initially set to 0% (can be increased as tests are added)

Directory Structure

tests/
├── __init__.py
├── conftest.py              # Shared pytest fixtures
├── test_setup_validation.py # Infrastructure validation tests
├── unit/
│   └── __init__.py
└── integration/
    └── __init__.py

Fixtures and Utilities

Created comprehensive fixtures in conftest.py:

• temp_dir: Creates temporary directories for testing
• sample_pdf_list: Provides sample PDF filenames
• mock_github_config: Mock GitHub configuration
• sample_readme_content: Sample README content
• temp_workspace: Creates a temporary workspace with sample files
• mock_os_system: Mocks os.system calls
• mock_github: Mocks GitHub API
• capture_stdout: Captures stdout for testing print statements
• change_test_dir: Automatically changes to test directory

Development Commands

Added Poetry script commands for convenience:

• poetry run test - Run all tests
• poetry run tests - Alternative command (both work)

Both commands support all standard pytest options.

Additional Updates

• Updated .gitignore with:
  • Testing-related entries (.pytest_cache/, .coverage, htmlcov/, etc.)
  • Claude-specific entries (.claude/*)
  • Note about committing poetry.lock for applications

How to Use

1. Install dependencies:

   poetry install

2. Run tests:

   poetry run test
   # or
   poetry run tests
   # or with options
   poetry run pytest -v -m unit

3. Run specific test markers:

   poetry run pytest -m unit      # Run only unit tests
   poetry run pytest -m integration  # Run only integration tests
   poetry run pytest -m "not slow"   # Skip slow tests

4. View coverage report:

   # After running tests, open the HTML report
   open htmlcov/index.html

Notes

• The infrastructure is set up but no actual unit tests for the existing code have been written
• Coverage threshold is currently set to 0% to allow the infrastructure to be merged
• The validation tests confirm that all testing components are properly configured
• Poetry was chosen as the default package manager since no existing package manager was detected
• The src/ directory was created to follow Python packaging best practices

Next Steps

1. Write unit tests for update_readme.py and add_commit_git_push.py
2. Increase coverage threshold as tests are added
3. Set up CI/CD pipeline to run tests automatically
4. Consider adding additional testing tools (e.g., tox for multi-version testing)