feat: Set up complete Python testing infrastructure with Poetry

[llbbl]

Set Up Python Testing Infrastructure

Summary

This PR establishes a comprehensive testing infrastructure for the ssh-ident project using Poetry as the package manager and pytest as the testing framework. The setup provides a ready-to-use testing environment where developers can immediately start writing tests.

Changes Made

Package Management

• Poetry Configuration: Created pyproject.toml with Poetry setup in package-mode=false (since ssh-ident is a standalone script)
• No Migration Required: No existing requirements.txt or setup.py files were found

Testing Dependencies

Added as development dependencies:

• pytest ^8.0.0 - Core testing framework
• pytest-cov ^5.0.0 - Coverage reporting
• pytest-mock ^3.14.0 - Mocking utilities

Testing Configuration

Configured in pyproject.toml:

• pytest settings:
  • Test discovery in tests/ directory
  • Coverage reporting (HTML, XML, terminal)
  • Custom markers: unit, integration, slow
  • Strict mode with verbose output
• coverage settings:
  • Source coverage for project root
  • Exclusions for test files, virtual envs, and build artifacts
  • HTML reports in htmlcov/, XML in coverage.xml

Directory Structure

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

Testing Fixtures

Created comprehensive fixtures in conftest.py:

• temp_dir - Temporary directory management
• temp_file - Temporary file creation
• mock_env_vars - Environment variable mocking
• mock_home_dir - Mock home directory
• mock_ssh_dir - Mock .ssh directory
• mock_config - Configuration mocking
• sample_ssh_key - Sample SSH key file
• sample_ssh_config - Sample SSH config
• capture_stdout - Stdout capture utility
• reset_modules - Module reset between tests

Additional Setup

Updated .gitignore with:

• Testing artifacts: .pytest_cache/, .coverage, htmlcov/, coverage.xml
• Python artifacts: __pycache__/, *.py[cod], *.egg-info/
• Development: virtual environments, IDE files, build artifacts
• Claude settings: .claude/*

How to Use

1. Install dependencies:

   poetry install

2. Run tests:

   poetry run pytest

3. Run tests with specific markers:

   poetry run pytest -m unit
   poetry run pytest -m integration
   poetry run pytest -m "not slow"

4. View coverage report:

   # After running tests, open the HTML report
   open htmlcov/index.html

Validation

All validation tests pass successfully:

• Testing tools are installed and available
• Directory structure is created correctly
• Fixtures are working properly
• Markers are configured
• Coverage reporting is functional

Notes

• Coverage threshold is currently set to 0% to allow initial setup without failing
• The project uses Poetry in non-package mode since ssh-ident is a standalone script
• Standard pytest options are available for all test runs
• The infrastructure is ready for developers to start writing actual unit and integration tests