feat: Add comprehensive Python testing infrastructure

[llbbl]

Add Comprehensive Python Testing Infrastructure

Summary

This PR establishes a complete testing infrastructure for the Raspberry Pi RP2040 platform project, providing developers with immediate capability to write and run tests effectively.

Changes Made

Package Management

• Set up Poetry as the package manager with pyproject.toml configuration
• Configured package-mode = false since this is a platform package, not a library
• Added PlatformIO dependency to support platform development

Testing Dependencies

• pytest (v8.0.0+) - Main testing framework
• pytest-cov (v4.0.0+) - Coverage reporting and analysis
• pytest-mock (v3.12.0+) - Advanced mocking utilities
• All added as development dependencies for clean separation

Testing Configuration

• Comprehensive pytest configuration in pyproject.toml:

  • Test discovery patterns for flexible test organization
  • Coverage settings with 80% threshold requirement
  • HTML and XML coverage report generation
  • Custom test markers: unit, integration, slow
  • Strict configuration and warning filters

• Coverage configuration with:

  • Source inclusion for platform.py and builder/ directory
  • Exclusion of test files, examples, and cache directories
  • Missing line reporting enabled

Directory Structure

• Organized test directories:

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

Shared Testing Utilities

• Comprehensive fixtures in conftest.py:
  • temp_dir - Temporary directory management
  • mock_platform_variables - Platform configuration mocking
  • mock_board_config - Board configuration utilities
  • sample_board_manifest - Test data for board configurations
  • mock_debug_config - Debug configuration mocking
  • mock_file_system - File system structure mocking
  • clean_environment - Environment cleanup between tests

Development Environment

• Updated .gitignore with testing-related entries:
  • Test cache and coverage files
  • Virtual environments and build artifacts
  • IDE files and OS-specific items
  • Claude settings directory

Validation

• Setup validation tests to verify:
  • Python import capabilities
  • Testing framework installation
  • Coverage tools availability
  • Project structure integrity
  • Platform module importability
  • Test markers functionality

Running Tests

Basic test execution:

poetry run pytest

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"    # Exclude slow tests

Coverage reporting:

poetry run pytest --cov            # With coverage
poetry run pytest --no-cov         # Without coverage

Test discovery and verbose output:

poetry run pytest -v               # Verbose output
poetry run pytest tests/unit/      # Specific directory

Installation

1. Install dependencies:

   poetry install

2. Verify setup:

   poetry run pytest tests/test_setup_validation.py -v

Notes

• No lock files in .gitignore: poetry.lock should be committed for reproducible builds
• PlatformIO integration: Tests can import and test platform modules with appropriate mocking
• Flexible configuration: Easy to adjust coverage thresholds and test discovery patterns
• Ready for CI/CD: Configuration supports automated testing pipelines

The testing infrastructure is now ready for immediate use. Developers can start writing unit and integration tests using the provided fixtures and configuration.

🤖 Generated with Claude Code