characterization-test-generator

# Characterization Test Generator Skill Generates characterization tests (also known as golden master tests or approval tests) to capture existing system behavior before migration, ensuring functional equivalence after changes. ## Purpose Enable behavior preservation during migration through: - Golden master test creation - Approval test generation - Edge case discovery - Input/output recording - Behavior snapshot capture - Regression baseline establishment ## Capabilities ### 1. Golden Master Test Creation - Capture current system outputs for given inputs - Store outputs as reference "golden" files - Generate comparison test infrastructure - Support multiple output formats - Enable baseline versioning ### 2. Approval Test Generation - Create human-reviewable test outputs - Generate diff-based comparison tests - Support approval workflows - Enable incremental approval - Track approval history ### 3. Edge Case Discovery - Analyze code paths for boundary conditions - Generate boundary value inputs - Identify error handling scenarios - Map exception paths - Create comprehensive test coverage ### 4. Input/Output Recording - Instrument code for I/O capture - Record API request/response pairs - Capture database interactions - Log external service calls - Store timing and sequence data ### 5. Behavior Snapshot - Capture state at key points - Record side effects - Document non-deterministic behavior - Identify environmental dependencies - Map configuration impacts ### 6. Re...