feat: add comprehensive Python testing infrastructure with Poetry

[llbbl]

Add Python Testing Infrastructure

Summary

This PR establishes a comprehensive testing infrastructure for the pysift project using Poetry for dependency management and pytest for testing.

Changes Made

1. Package Management

• Poetry Setup: Created pyproject.toml with project metadata and dependencies
• Dependency Migration: Migrated dependencies from README to Poetry configuration
• Development Dependencies: Added pytest, pytest-cov, and pytest-mock as dev dependencies

2. Testing Configuration

• pytest Configuration:

  • Configured test discovery patterns
  • Set up coverage reporting with HTML and XML output
  • Added custom markers: unit, integration, slow, performance
  • Enabled strict mode and verbose output
  • Coverage threshold set to 0% (should be changed to 80% when actual tests are added)

• Coverage Configuration:

  • Source directory set to pysift
  • Branch coverage enabled
  • Exclusion patterns for non-testable code
  • HTML and XML report generation

3. Testing Structure

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

4. Pytest Fixtures

Created comprehensive fixtures in conftest.py:

• temp_dir: Temporary directory for test files
• sample_image: Color test image (100x100)
• grayscale_image: Grayscale test image
• sample_keypoints: OpenCV KeyPoint objects
• sample_descriptors: Mock SIFT descriptors
• mock_config: Configuration dictionary
• test_image_path: Saved test image path
• capture_stdout: Stdout capture utility
• mock_sift_detector: Mocked SIFT detector

5. Poetry Scripts

Added convenient test commands:

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

6. Additional Changes

• Created .gitignore with comprehensive Python patterns
• Added validation tests to verify the infrastructure works
• Used opencv-python-headless to avoid GUI dependencies in tests

How to Use

1. Install dependencies:

   poetry install

2. Run tests:

   poetry run test        # or
   poetry run tests       # or
   poetry run pytest      # with custom options

3. Run specific test categories:

   poetry run pytest -m unit              # Unit tests only
   poetry run pytest -m integration       # Integration tests only
   poetry run pytest -m "not slow"        # Exclude slow tests

4. View coverage report:

   # After running tests, open htmlcov/index.html in a browser

Notes

• The coverage threshold is currently set to 0% to allow the infrastructure to be merged without actual tests. This should be changed to 80% in pyproject.toml once unit tests are added.
• All validation tests pass, confirming the infrastructure is properly configured.
• The project uses opencv-python-headless to avoid GUI dependencies in CI/testing environments.
• Poetry lock file is created and should be committed to ensure reproducible builds.

Next Steps

With this infrastructure in place, developers can now:

1. Write unit tests in tests/unit/
2. Write integration tests in tests/integration/
3. Use the provided fixtures for common testing needs
4. Run tests with coverage to ensure code quality