feat: Set up comprehensive Python testing infrastructure with Poetry

[llbbl]

Python Testing Infrastructure Setup

Summary

This PR establishes a comprehensive testing infrastructure for the Python project 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.

Changes Made

Package Management

• ✅ Detected and utilized existing Poetry configuration
• ✅ Added testing dependencies as development dependencies (not production)

Testing Dependencies Added

• pytest (^8.3.3) - Main testing framework
• pytest-cov (^5.0.0) - Coverage reporting with HTML/XML output
• pytest-mock (^3.14.0) - Mocking utilities for unit tests

Testing Configuration (pyproject.toml)

• pytest settings:

  • Test discovery patterns configured for test_*.py and *_test.py
  • Coverage reporting with 80% threshold requirement
  • HTML and XML coverage reports generation
  • Strict markers enabled for better test organization
  • Custom markers defined: unit, integration, slow

• Coverage settings:

  • Source directory set to src/
  • Exclusions configured for test files, migrations, and boilerplate code
  • Branch coverage enabled
  • Multiple report formats (terminal, HTML, XML)

Directory Structure Created

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

Shared Fixtures (conftest.py)

• temp_dir - Temporary directory with automatic cleanup
• temp_file - Create temporary files for testing
• mock_config - Mock configuration object
• mock_logger - Mock logger for testing logging
• sample_json_data - Sample JSON data fixture
• json_file - Create temporary JSON files
• mock_env_vars - Mock environment variables
• mock_http_response - Mock HTTP responses
• mock_database_connection - Mock database connections
• capture_stdout - Capture print output for testing
• reset_modules - Clean module state between tests

Development Commands

Both commands are now available via Poetry:

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

All standard pytest options are available (e.g., poetry run test -v, poetry run test -k unit)

.gitignore Updates

Added comprehensive Python and testing-related entries:

• Testing artifacts (.pytest_cache/, .coverage, htmlcov/, coverage.xml)
• Python artifacts (__pycache__/, *.py[cod], .eggs/)
• Virtual environments (venv/, .venv/)
• IDE files (.vscode/, .idea/)
• Claude settings (.claude/)
• Build artifacts and temporary files

How to Use

Install Dependencies

poetry install

Run Tests

# Run all tests
poetry run test

# Run with verbose output
poetry run test -v

# Run only unit tests
poetry run test -m unit

# Run tests with coverage report
poetry run test --cov

# Run specific test file
poetry run test tests/test_validation.py

Writing Tests

1. Place unit tests in tests/unit/
2. Place integration tests in tests/integration/
3. Use the provided fixtures from conftest.py
4. Mark tests appropriately with @pytest.mark.unit, @pytest.mark.integration, or @pytest.mark.slow

Coverage Reports

After running tests, coverage reports are available in:

• Terminal output (shows missing lines)
• htmlcov/index.html - Interactive HTML report
• coverage.xml - XML report for CI/CD integration

Validation

The infrastructure has been validated with 18 tests that verify:

• All dependencies are properly installed
• Directory structure is correctly created
• All fixtures work as expected
• Test markers are properly configured
• Poetry scripts function correctly

Notes

• The project uses Poetry for dependency management, which provides better dependency resolution and lock file management compared to pip
• Coverage threshold is set to 80% - tests will fail if coverage drops below this
• The poetry.lock file should be committed to ensure reproducible builds
• No actual unit tests for the codebase were written - only infrastructure setup and validation tests