DRY Refactoring Guide

Help users eliminate code duplication by extracting shared logic into reusable modules.

When This Applies

• User mentions "duplicates", "DRY", "repeated code", "copy-paste"
• /bluera-base:dry scan found duplicates that need refactoring
• Code review identified similar patterns across files

When Duplication is Acceptable

Not all duplication is bad. Keep duplicates when:

1. Test code: Explicit test cases can repeat for clarity
2. Generated code: Don't DRY generated files
3. Incidental similarity: Coincidentally similar code that may diverge
4. Coupling cost: Extraction would create tight coupling between unrelated modules

Refactoring Workflow

1. Analyze the Duplicates

# Run scan if not already done
/bluera-base:dry scan

# Review the report
/bluera-base:dry report

2. Categorize Each Duplicate

3. Choose Extraction Target

4. Execute Extraction

1. Create the shared abstraction
2. Move one instance, verify tests pass
3. Replace remaining instances
4. Update imports/exports
5. Run tests after each replacement

5. Validate

• All tests pass
• No circular dependencies introduced
• Public API unchanged (if applicable)
• Code is actually simpler (not over-abstracted)

Anti-patterns to Avoid

1. Wrong abstraction: Forcing unrelated code together
2. Over-parameterization: Too many config options
3. Premature extraction: Extracting before patterns stabilize
4. Leaky abstraction: Exposing implementation details

Language-Specific Patterns

See skills/dry-refactor/references/patterns.md for detailed examples:

Report Integration

When /bluera-base:dry scan identifies duplicates:

1. Review the report at .bluera/bluera-base/state/dry-report.md
2. Start with highest-impact duplicates (most tokens/instances)
3. Use suggested extraction targets from the report
4. Re-run /bluera-base:dry scan after refactoring to verify reduction