feat: Set up Python testing infrastructure with Poetry

[llbbl]

Add Python Testing Infrastructure

Summary

This PR sets up a complete testing infrastructure for the Python project using Poetry as the package manager and pytest as the testing framework. The infrastructure is ready for developers to immediately start writing tests without any additional setup.

Changes Made

Package Management

• Poetry Configuration: Created pyproject.toml with Poetry as the package manager
• Dependencies: Added testing dependencies as development dependencies:
  • pytest (^7.4.0) - Main testing framework
  • pytest-cov (^4.1.0) - Coverage reporting
  • pytest-mock (^3.11.1) - Mocking utilities

Testing Configuration

• Test Discovery: Configured pytest to discover tests in the tests/ directory
• Coverage Settings:
  • 80% coverage threshold enforced
  • HTML and XML coverage reports generated
  • Coverage excludes test files and common non-code directories
• Custom Markers:
  • unit: For fast, isolated unit tests
  • integration: For tests with dependencies
  • slow: For slow-running tests (skipped by default, use --runslow to include)

Directory Structure

/workspace/
├── pyproject.toml          # Poetry and testing configuration
├── .gitignore              # Updated with testing entries
├── coding_algorithms/      # Main package directory
│   └── __init__.py
└── tests/                  # Test directory
    ├── __init__.py
    ├── conftest.py         # Shared pytest fixtures
    ├── test_setup_validation.py  # Infrastructure validation tests
    ├── unit/               # Unit tests directory
    │   └── __init__.py
    └── integration/        # Integration tests directory
        └── __init__.py

Shared Fixtures (in conftest.py)

• temp_dir: Creates temporary directory for test files
• temp_file: Creates temporary file with content
• mock_config: Provides mock configuration dictionary
• sample_data: Sample data sets for algorithm testing
• captured_output: Captures stdout/stderr for testing print statements
• mock_env_vars: Sets mock environment variables
• reset_sys_modules: Ensures clean imports between tests

Running Tests

After installing dependencies with poetry install, you can run tests using:

# Run all tests
poetry run test
# or
poetry run tests

# Run with specific options
poetry run pytest -v                    # Verbose output
poetry run pytest tests/unit/           # Run only unit tests
poetry run pytest -m integration        # Run only integration tests
poetry run pytest --runslow             # Include slow tests
poetry run pytest --cov-report=html     # Generate HTML coverage report

.gitignore Updates

Added entries for:

• Testing artifacts (.pytest_cache/, coverage.xml, htmlcov/)
• Python build artifacts
• Virtual environments
• IDE files
• Claude-specific directory (.claude/*)

Notes

• The infrastructure is set up but no actual unit tests for the codebase were written - this PR only provides the testing foundation
• Poetry.lock file is intentionally not gitignored as it should be committed for reproducible builds
• Coverage is configured to fail the build if it drops below 80%
• All tests pass validation, confirming the infrastructure is properly configured

Next Steps

Developers can now:

1. Write unit tests in tests/unit/
2. Write integration tests in tests/integration/
3. Use the provided fixtures for common testing scenarios
4. Run tests with coverage reporting to ensure code quality