feat: Set up comprehensive Python testing infrastructure with Poetry

[llbbl]

Python Testing Infrastructure Setup

Summary

This PR establishes a complete Python testing infrastructure using Poetry as the package manager and pytest as the testing framework. The setup provides a robust foundation for test-driven development with comprehensive fixtures, coverage reporting, and organized test structure.

Changes Made

Package Management

• ✅ Detected existing Poetry configuration in pyproject.toml
• ✅ Added testing dependencies as development dependencies:
  • pytest ^8.0.0 - Core testing framework
  • pytest-cov ^5.0.0 - Coverage reporting
  • pytest-mock ^3.14.0 - Mocking utilities

Testing Configuration

• ✅ Configured pytest settings in pyproject.toml:

  • Test discovery patterns for flexible test naming
  • Coverage reporting with HTML, XML, and terminal output
  • 80% coverage threshold enforcement
  • Custom test markers: unit, integration, slow
  • Strict marker enforcement and comprehensive warning filters

• ✅ Configured coverage settings:

  • Excluded non-source directories from coverage
  • Proper handling of abstract methods and type checking blocks
  • HTML and XML report generation

Directory Structure

tests/
├── __init__.py
├── conftest.py                      # Shared fixtures
├── test_infrastructure_validation.py # Validation tests
├── unit/
│   └── __init__.py
└── integration/
    └── __init__.py

Shared Fixtures (conftest.py)

Implemented comprehensive fixtures for common testing needs:

• File System: temp_dir, temp_file, mock_file_system
• Configuration: mock_config, json_file, mock_env_vars
• Mocking: mock_logger, mock_http_response, mock_database_connection
• Testing Utilities: benchmark_timer, sample_data, mock_async_function
• Auto-cleanup: reset_singleton_instances (runs automatically)

Validation Tests

Created test_infrastructure_validation.py with 27 tests covering:

• Pytest functionality verification
• Custom marker validation
• All fixture functionality
• Coverage configuration
• Project structure verification
• pytest-mock integration

Git Configuration

• ✅ Created comprehensive .gitignore file with:
  • Python build artifacts and cache files
  • Testing output directories
  • IDE and editor files
  • Virtual environment directories
  • Claude settings directory

How to Use

Installing Dependencies

# Install all dependencies
poetry install --no-root

# Or if you want to include the project itself
poetry install

Running Tests

# Run all tests
poetry run pytest

# Run without coverage
poetry run pytest --no-cov

# Run only unit tests
poetry run pytest -m unit

# Run only integration tests  
poetry run pytest -m integration

# Run with specific verbosity
poetry run pytest -v  # verbose
poetry run pytest -q  # quiet

# Run specific test file
poetry run pytest tests/test_infrastructure_validation.py

# Run with coverage report
poetry run pytest --cov --cov-report=html

Writing New Tests

1. Place unit tests in tests/unit/
2. Place integration tests in tests/integration/
3. Use fixtures from conftest.py for common test needs
4. Mark tests appropriately:

   import pytest
   
   @pytest.mark.unit
   def test_my_unit_test(temp_dir, mock_logger):
       # Your test code here
       pass
   
   @pytest.mark.integration
   def test_my_integration_test(mock_database_connection):
       # Your test code here
       pass
   

Validation Results

✅ All 27 validation tests pass successfully ✅ Testing infrastructure is fully operational ✅ Coverage reporting is configured (will work once source code is added) ✅ Custom markers are functional ✅ All fixtures work as expected

Notes

• The project uses Poetry for dependency management
• Coverage threshold is set to 80% (will apply once source code exists)
• The poetry.lock file is tracked in git for reproducible builds
• Tests run in verbose mode by default with strict marker enforcement
• The infrastructure is ready for immediate test development