Rails Concern Generator (TDD)

Creates concerns (ActiveSupport::Concern modules) for shared behavior with specs first.

Quick Start

1. Write failing spec testing the concern behavior
2. Run spec to confirm RED
3. Implement concern in app/models/concerns/ or app/controllers/concerns/
4. Run spec to confirm GREEN

When to Use Concerns

Good use cases:

• Shared validations across multiple models
• Common scopes used by several models
• Shared callbacks (e.g., UUID generation)
• Controller authentication/authorization helpers
• Pagination or filtering logic