feat: Set up comprehensive Python testing infrastructure with Poetry

[llbbl]

Set Up Python Testing Infrastructure

Summary

This PR establishes a comprehensive testing infrastructure for the MoE++ Python project, providing developers with a ready-to-use testing environment powered by Poetry and pytest.

Changes Made

Package Management

• Poetry configured as the primary package manager
• Created pyproject.toml with project metadata and dependencies
• Generated poetry.lock file for reproducible builds

Testing Dependencies

Added the following development dependencies:

• pytest (^7.4.0) - Core testing framework
• pytest-cov (^4.1.0) - Coverage reporting integration
• pytest-mock (^3.11.1) - Mocking utilities for tests

Testing Configuration

pytest Configuration (pyproject.toml)

• Minimum pytest version: 7.0
• Automatic test discovery in tests/ directory
• Coverage reporting with 80% threshold
• Multiple output formats: terminal, HTML, and XML
• Custom markers: unit, integration, slow
• Strict mode enabled for better error detection

Coverage Configuration

• Source directory: MoE++
• Branch coverage enabled
• Exclusions for test files and common patterns
• HTML reports in htmlcov/ directory
• XML reports for CI integration

Directory Structure

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

Shared Fixtures (conftest.py)

• temp_dir - Temporary directory management
• mock_config - Sample configuration for testing
• sample_data - Test data sets
• env_vars - Environment variable management
• reset_modules - Module state cleanup
• mock_file_system - File system mocking
• capture_logs - Log capture utilities

Development Commands

Both commands are available and execute pytest:

• poetry run test - Run all tests
• poetry run tests - Alternative command

Git Configuration

Updated .gitignore with:

• Python-specific patterns
• Testing artifacts (coverage reports, caches)
• IDE files
• Claude settings (.claude/*)
• Note: poetry.lock is NOT ignored (best practice)

How to Use

1. Install dependencies:

   poetry install

2. Run all tests:

   poetry run test
   # or
   poetry run tests

3. Run specific tests:

   poetry run pytest tests/unit/
   poetry run pytest -m unit
   poetry run pytest tests/test_specific.py::test_function

4. View coverage report:

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

Validation

The setup includes test_setup_validation.py which verifies:

• pytest is properly configured
• All fixtures are working correctly
• Coverage tracking is functional
• Test markers are recognized
• Mocking capabilities are available

All validation tests pass successfully, confirming the infrastructure is ready for use.

Notes

• Coverage currently shows 0% as no actual tests for the MoE++ modules exist yet
• The 80% coverage threshold will need actual module tests to pass
• The infrastructure is designed to scale with the project's growth
• All standard pytest plugins and options are available