Lab 4 — Scripted Refactoring

Goal

Automate a sequence of small refactorings that moves code toward a design pattern.

Example targets:

• conditional → Strategy;
• telescoping construction → Builder;
• direct vendor dependency → Adapter;
• subclass explosion → Bridge;
• optional responsibilities → Decorator.

Required safety checks

• parse/type/compile success where applicable;
• precondition checks;
• tests before and after;
• deterministic diff output;
• rollback on failure.

Report

Explain which parts of the transformation are syntactic and which require semantic/design judgment.