feat: Set up comprehensive Python testing infrastructure

[llbbl]

Set up comprehensive Python testing infrastructure

Summary

This PR establishes a complete testing infrastructure for the achoz project, migrating from the old setup.py based configuration to a modern Poetry-based development environment with comprehensive testing capabilities.

Changes Made

Package Management Migration

• Migrated from setup.py to Poetry: Created comprehensive pyproject.toml with all project metadata
• Dependency Management: Moved all production dependencies from setup.py to Poetry configuration
• Development Dependencies: Added testing dependencies as a separate development group

Testing Infrastructure

• Testing Framework: Set up pytest with comprehensive configuration
• Coverage Reporting: Configured pytest-cov with 80% coverage threshold
• Test Organization: Created structured test directories (tests/unit/ and tests/integration/)
• Shared Fixtures: Comprehensive conftest.py with reusable testing utilities
• Custom Markers: Added unit, integration, and slow test markers for test categorization

Configuration Details

• pytest configuration: Strict markers, verbose output, coverage reporting (HTML/XML)
• Coverage settings: Source code tracking, exclusion patterns, reporting thresholds
• Test discovery: Automatic test file pattern matching and collection
• Isolation: Automatic test isolation with temporary directories and mocked global state

Code Quality Improvements

• Import fixes: Updated all internal imports to use relative imports for proper package structure
• Module resolution: Fixed import issues that prevented proper testing
• Validation tests: Created comprehensive validation test suite to ensure infrastructure works

Development Environment

• Git integration: Updated .gitignore with testing artifacts, IDE files, and environment exclusions
• Ready-to-use setup: Complete environment that allows immediate test development
• Documentation: Comprehensive fixtures and examples for common testing scenarios

Testing Infrastructure Components

Core Testing Dependencies

pytest = "^7.4.0"           # Main testing framework
pytest-cov = "^4.1.0"       # Coverage reporting
pytest-mock = "^3.11.1"     # Mocking utilities

Available Fixtures

• temp_dir - Temporary directory for file operations
• temp_file - Pre-created temporary file for testing
• mock_config - Mock configuration dictionary
• mock_global_vars - Mocked global variables with automatic cleanup
• mock_meilisearch_client - Mock MeiliSearch client for testing
• sample_documents - Sample document data for indexing tests
• sample_test_files - Pre-created test files with various extensions
• mock_logger - Mock logger to suppress output during tests
• clean_environment - Environment variable isolation
• mock_requests - Mock HTTP requests library

Test Markers

• @pytest.mark.unit - Unit tests
• @pytest.mark.integration - Integration tests
• @pytest.mark.slow - Slow-running tests

How to Run Tests

Install Dependencies

poetry install

Run All Tests

poetry run pytest

Run with Coverage Report

poetry run pytest --cov=achoz --cov-report=html

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"    # Skip slow tests

Coverage Reports

• Terminal: Real-time coverage shown during test runs
• HTML Report: Generated in htmlcov/ directory
• XML Report: Generated as coverage.xml for CI/CD integration

Validation

The infrastructure includes comprehensive validation tests that verify:

• All testing fixtures work correctly
• Module imports function properly
• Configuration is valid and complete
• Coverage reporting generates properly
• Test markers and categorization work

Current validation status: ✅ 18 passed, 1 skipped (OpenCV dependency optional)

Notes for Developers

Writing Tests

1. Place unit tests in tests/unit/
2. Place integration tests in tests/integration/
3. Use the provided fixtures from conftest.py
4. Mark tests appropriately with @pytest.mark.unit, @pytest.mark.integration, etc.
5. Follow the 80% coverage threshold requirement

Development Workflow

1. Write tests alongside code development
2. Run tests frequently: poetry run pytest
3. Check coverage: poetry run pytest --cov-report=html
4. Use appropriate fixtures to mock external dependencies
5. Ensure all tests pass before committing

Dependencies Management

• Lock file (poetry.lock) is tracked in git
• Use poetry add <package> for production dependencies
• Use poetry add --group dev <package> for development dependencies
• Use poetry install to set up environment from scratch

This testing infrastructure provides a solid foundation for maintaining code quality and enabling confident development and refactoring of the achoz codebase.