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 attention-based image caption generation project using Poetry as the package manager and pytest as the testing framework.

Changes Made

Package Management

• Poetry Setup: Created pyproject.toml with Poetry configuration as the primary package manager
• Dependencies: Migrated existing dependencies (numpy, theano, scikit-learn, etc.) to Poetry
• Dev Dependencies: Added pytest (^7.4.0), pytest-cov (^4.1.0), and pytest-mock (^3.11.0)

Testing Configuration

• pytest Configuration:

  • Configured test discovery patterns for test_*.py and *_test.py files
  • Added custom test markers: unit, integration, and slow
  • Set up verbose output with strict markers
  • Configured coverage reporting with HTML and XML outputs

• Coverage Configuration:

  • Source directories configured with appropriate exclusions
  • HTML coverage reports output to htmlcov/
  • XML coverage report outputs to coverage.xml
  • Excluded test files, virtual environments, and cache directories

Directory Structure

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

Shared Fixtures (conftest.py)

• temp_dir: Creates temporary directories for test files
• mock_config: Provides mock configuration dictionaries
• sample_image_features: Generates sample image features
• sample_captions: Provides test captions
• sample_vocabulary: Creates test vocabularies
• model_params: Provides sample model parameters
• mock_data_iterator: Creates mock data iterators
• Additional utility fixtures for testing

Development Commands

Two equivalent commands are available for running tests:

• poetry run test
• poetry run tests

Both commands run pytest with all configured options.

.gitignore Updates

Added entries for:

• Testing artifacts: .pytest_cache/, .coverage, htmlcov/, coverage.xml
• Claude settings: .claude/*
• Virtual environments and IDE files
• Note: poetry.lock is intentionally NOT ignored (should be committed)

Running Tests

1. Install dependencies:

   poetry install --with dev

2. Run all tests:

   poetry run test
   # or
   poetry run tests

3. Run specific test types:

   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. Run without coverage:

   poetry run pytest --no-cov

Validation

The setup has been validated with a test suite (test_setup_validation.py) that verifies:

• pytest is working correctly
• All fixtures are accessible
• Coverage reporting is configured
• pytest-mock is functional
• Test directory structure is correct
• File operations work in temporary directories

All validation tests pass successfully.

Notes

• Coverage threshold is currently set to 0% due to Python 2 syntax in existing files
• The infrastructure is ready for developers to start writing tests immediately
• All testing dependencies are isolated as development dependencies
• The setup follows Python testing best practices with proper directory structure and configuration