feat: implement Datest MVP with Dana test framework integration

[ctn]

feat: implement Datest MVP with Dana test framework integration

Summary

This PR implements the complete Datest MVP - a Dana-native testing framework that provides comprehensive test discovery, execution, and reporting for Dana (.na) files. This is a major milestone that transforms the project from a simple rename to a fully functional testing framework.

🎯 Major Implementation

Complete Testing Framework

• Test Discovery: Configurable file patterns, recursive directory traversal
• Dana Execution: Subprocess-based execution with timeout support
• Assertion Parsing: Parses Dana assertions, logs, and errors from both text and JSON output
• Rich Reporting: Colored console output with detailed assertion display
• pytest Integration: Seamless .na file discovery in pytest workflows
• Configuration System: TOML-based configuration with command-line overrides

Core Modules Implemented

• datest/discovery.py - Test file discovery with pattern matching
• datest/executor.py - Dana runtime execution and process management
• datest/assertions.py - Assertion parsing and validation
• datest/models.py - Data models for test files, assertions, and results
• datest/reporter.py - Rich console reporting with colors and formatting
• datest/config.py - Configuration management with TOML support
• datest/pytest_plugin.py - Full pytest integration for .na files

Comprehensive Testing

• Unit Tests: Complete coverage for all modules
• Integration Tests: Full pipeline testing with mocked Dana
• End-to-End Tests: CLI and configuration testing
• Test Fixtures: Example Dana test files demonstrating usage

🚀 Key Features

Test Discovery & Execution

# Basic usage
datest tests/

# Discovery only
datest --discover-only tests/

# Verbose with custom pattern
datest -v --pattern "spec_*.na" tests/

# With configuration file
datest --config myconfig.toml tests/

# JSON output with timeout
datest --json --timeout 60 tests/

pytest Integration

# Automatic .na file discovery
pytest tests/

# With Dana-specific options
pytest --dana-json --dana-timeout 45 tests/

Configuration Support

[discovery]
patterns = ["test_*.na", "*_test.na"]
exclude = [".*", "__pycache__"]
recursive = true

[execution]
command = "dana"
timeout = 30.0
json_output = false

[output]
verbose = false
color = true
timings = true

📊 Implementation Details

Assertion Parsing

• Parses Dana output for assertions, logs, and errors
• Supports both text and JSON output formats
• Extracts line numbers and pass/fail status
• Handles complex assertion patterns

Error Handling

• Graceful handling of Dana command unavailability
• Timeout management for long-running tests
• Detailed error reporting with context
• Proper exit codes (0=success, 1=failures, 2=errors)

Performance & Reliability

• Efficient file discovery with pattern matching
• Robust subprocess execution with cleanup
• Memory-efficient parsing of large outputs
• Comprehensive error recovery

🔧 Technical Improvements

• Project Structure: Organized into logical modules with clear separation of concerns
• Dependencies: Updated pyproject.toml with proper dependency management
• Documentation: Comprehensive implementation summary and usage examples
• Testing: Full test suite with fixtures and integration tests
• CLI: Enhanced command-line interface with multiple options

✅ Testing Completed

• Test discovery with various patterns
• Dana execution with timeout and error handling
• Assertion parsing for text and JSON output
• Rich reporting with colors and formatting
• pytest integration and plugin functionality
• Configuration file loading and validation
• CLI options and argument parsing
• Unit tests for all modules
• Integration tests for full pipeline
• End-to-end tests for CLI functionality

🎉 Impact

This implementation transforms Datest from a simple project rename into a production-ready testing framework for Dana language files. The framework provides:

• ✅ Complete test discovery and execution pipeline
• ✅ Rich assertion parsing and reporting
• ✅ Full pytest integration
• ✅ Flexible configuration system
• ✅ Comprehensive error handling
• ✅ Extensive test coverage

The MVP is now ready for real-world usage and provides a solid foundation for future enhancements like parallel execution, coverage analysis, and advanced Dana-specific assertions.

📝 Breaking Changes

None - this is a complete implementation that maintains backward compatibility while adding significant new functionality.