Refactor

Rules

• Verify existing tests pass before starting. If no tests exist, write them first.
• Make one change at a time. Each step should leave the code in a working state.
• Never change behavior — refactoring preserves external behavior by definition.
• Run tests after each step to confirm nothing broke.
• If a refactoring is too large, break it into smaller sequential steps.
• Prefer renaming over introducing new abstractions.
• Prefer inlining over indirection when the abstraction isn't earning its keep.
• Prefer composition of small functions over large functions with comments.
• Delete dead code — don't comment it out.
• Follow the project's existing patterns and conventions.

Common Refactorings

• Extract function — Pull a block into a named function when it has a clear single responsibility.
• Inline function — Replace a trivial wrapper with its body.
• Rename — Change a name to better express intent. Update all references.
• Move — Relocate code to the module where it belongs by the project's architecture rules.
• Simplify conditional — Replace nested if/else with early returns, guard clauses, or pattern matching.
• Replace loop with pipeline — Convert for/forEach to map/filter/reduce.
• Extract type — Pull inline types into named types when reused.

Output

1. What you're changing and why.
2. The code change.
3. Confirmation that tests still pass.