Multi-Version Behavior Comparator

Overview

This skill compares behavior across multiple versions of programs, identifying functional changes, regressions, and behavioral divergences to guide safe upgrades and validation.

Quick Start

# Compare two versions
python scripts/compare.py v1.0/ v2.0/

# Compare multiple versions with test suite
python scripts/compare.py v1.0/ v2.0/ v3.0/ --tests tests/

# Generate detailed report
python scripts/compare.py old/ new/ --output report.json

What Gets Compared

1. Functionality - Added, removed, or modified features
2. Outputs - Return values, printed output, file changes
3. Exceptions - Error handling and exception types
4. Test Results - Pass/fail status across versions
5. Observable States - Side effects, state changes

Comparison Report

Generates JSON report with:

• Behavioral Divergences: Where versions behave differently
• Potential Regressions: Functionality that may have broken
• Added Features: New functionality in newer versions
• Removed Features: Functionality no longer present
• Validation Areas: Code requiring manual review

Usage

python scripts/compare.py <version1> <version2> [version3...] [--tests <test_dir>] [--output <report.json>]

Tips

• Run before deploying new versions
• Use with existing test suites for comprehensive comparison
• Review regressions carefully before upgrading
• Validate high-risk areas identified in report