feat: Add complete Python testing infrastructure with Poetry

[llbbl]

Add Complete Python Testing Infrastructure

Summary

This PR sets up a comprehensive testing infrastructure for the ResNet 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 coverage reporting and test organization.

Changes Made

Package Management

• Poetry Setup: Created pyproject.toml with Poetry configuration as the project's package manager
• Dependencies: Added core dependencies (torch, torchvision, pillow, numpy) and development dependencies (pytest, pytest-cov, pytest-mock)
• Script Commands: Configured both poetry run test and poetry run tests commands for running tests

Testing Configuration

• pytest Configuration:

  • Set up test discovery patterns for test_*.py and *_test.py files
  • Configured strict markers and error handling
  • Added custom markers: unit, integration, and slow for test categorization

• Coverage Configuration:

  • Set 80% coverage threshold
  • Configured HTML, XML, and terminal coverage reports
  • Excluded test files, cache directories, and virtual environments from coverage

Directory Structure

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

Fixtures and Testing Utilities

Created comprehensive fixtures in conftest.py:

• temp_dir: Temporary directory management
• sample_image_path: Mock image file creation
• mock_model_config: Model configuration for testing
• mock_dataset_config: Dataset configuration for testing
• device: PyTorch device selection
• sample_tensor & sample_batch: Test data generation
• reset_random_seeds: Reproducibility fixture
• mock_checkpoint: Model checkpoint creation
• environment_setup: Environment variable management

Additional Files

• .gitignore: Comprehensive Python gitignore with testing artifacts, IDE files, and project-specific patterns
• CLAUDE.md: Documentation for Claude AI with testing commands and project structure
• Validation Tests: Created tests to verify the infrastructure setup works correctly

How to Use

1. Install dependencies:

   poetry install

2. Run tests:

   # Run all tests
   poetry run test
   
   # Run with coverage
   poetry run pytest --cov=. --cov-report=term --cov-report=html
   
   # Run specific test categories
   poetry run pytest -m unit
   poetry run pytest -m integration
   poetry run pytest -m "not slow"

3. View coverage reports:

   • Terminal: Shown after test run
   • HTML: Open htmlcov/index.html in browser
   • XML: Available at coverage.xml for CI integration

Next Steps

With this infrastructure in place, developers can now:

1. Write unit tests for individual functions and classes
2. Create integration tests for end-to-end workflows
3. Add more specialized fixtures as needed
4. Integrate with CI/CD pipelines using the coverage reports

Notes

• Poetry was chosen as the package manager since no existing package manager was detected
• The 80% coverage threshold is configured but can be adjusted in pyproject.toml
• All testing dependencies are properly isolated as development dependencies
• The validation test suite confirms that all components are working correctly