refactoring-code

Perform behavior-preserving refactors on legacy code by first adding narrow characterization checks to establish a safety net. Execute small, verifiable increments and reuse the repository's existing tests to ensure observable behavior remains unchanged throughout the process.

The best way to split a large function without changing output is to slice the refactor into single-intention steps such as extracting phases or isolating side effects. Verify each incremental change against existing tests to preserve observable behavior and protect public APIs.

To extract shared logic from duplicate handlers safely, define a refactor contract and identify the smallest useful scope. Apply incremental, verifiable steps while relying on existing tests or lightweight characterization checks to prevent altering observable behavior.

Yes, you can refactor code alongside feature changes by using sequencing heuristics. Separate the structural refactor from the feature change into distinct incremental steps, verifying behavior preservation after each modification to maintain stability.

Use characterization checks during code maintenance when existing tests are insufficient, particularly for brittle modules or legacy code. They provide a lightweight safety net to verify behavior preservation before applying incremental refactors.

Yes, incremental refactoring explicitly protects public APIs, persisted formats, and CLI surfaces. By enforcing small, verifiable steps and reusing the repository's verification path, it ensures externally observable behavior remains completely unchanged.