feat: Set up Python testing infrastructure with Poetry and pytest

[llbbl]

Python Testing Infrastructure Setup

Summary

This PR sets up a comprehensive testing infrastructure for the Python project using Poetry as the package manager and pytest as the testing framework. The setup provides a solid foundation for writing and maintaining tests with proper organization, coverage reporting, and development tooling.

Changes Made

Package Management

• Poetry Configuration: Set up Poetry as the package manager with pyproject.toml
• Dependency Management: Added numpy as a project dependency (detected from existing code usage)
• Development Dependencies: Added pytest, pytest-cov, and pytest-mock as dev dependencies

Testing Framework Setup

• pytest Configuration:

  • Configured test discovery patterns
  • Set coverage threshold at 80%
  • Added strict markers and comprehensive reporting options
  • Created custom test markers: unit, integration, slow

• Coverage Configuration:

  • HTML and XML report generation
  • Source code coverage tracking
  • Exclusion patterns for test files and virtual environments

Directory Structure

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

Testing Fixtures (conftest.py)

Created comprehensive shared fixtures for common testing needs:

• temp_dir and temp_file: Temporary file/directory management
• mock_config: Mock configuration objects
• sample_data: Sample numpy data generation
• mock_dataset: Mock dataset for ML testing
• numpy_array_fixture: Common numpy arrays
• torch_tensor_fixture: PyTorch tensors (when available)
• reset_random_seeds: Reproducible test runs
• capture_stdout: Output capture for testing print statements
• mock_file_operations: Mock file I/O operations
• time_tracker: Performance measurement

Development Experience

• Poetry Scripts: Added poetry run test and poetry run tests commands
• GitIgnore Updates: Added patterns for:
  • Testing artifacts (.pytest_cache/, .coverage, htmlcov/, etc.)
  • Claude settings (.claude/*)
  • Virtual environments and build artifacts
  • IDE files

How to Use

1. Install dependencies:

   poetry install

2. Run tests:

   poetry run test
   # or
   poetry run tests
   # or directly with pytest
   poetry run pytest

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 reports:

   • Terminal: Included in test output
   • HTML: Open htmlcov/index.html after running tests
   • XML: Available at coverage.xml for CI integration

Validation

The setup includes validation tests that verify:

• Project structure is correctly configured
• All dependencies can be imported
• Custom fixtures work as expected
• Test markers are properly configured
• Coverage reporting functions correctly

All validation tests pass successfully.

Notes

• The project had syntax warnings in src/train_torch_filter.py that should be addressed separately
• Coverage is currently at 0% as no actual unit tests for the source code have been written yet
• The infrastructure is ready for immediate test development