TDD Reference

Practical guidance for test-driven development: writing good tests, designing testable interfaces, mocking correctly, and refactoring safely.

Scope Constraints

• Read-only reference skill — provides guidance, does not modify code
• Does not run tests, generate test files, or configure test runners
• Complements superpowers:test-driven-development workflow skill

Inputs

• Context (required): What the user is testing or designing
• Phase (optional): red (writing failing test), green (making it pass), refactor (cleaning up)

Input Sanitization

• Context descriptions: free text, reject null bytes.

Procedure

1. Identify the TDD phase. If unclear, ask: "Are you writing a new test, making one pass, or refactoring?"
2. Load the reference file matching the phase or question:
   • Writing tests → references/tests.md
   • Designing interfaces for testability → references/interface-design.md
   • Mocking decisions → references/mocking.md
   • Refactoring after green → references/refactoring.md
   • Module depth and API design → references/deep-modules.md
3. Apply the reference guidance to the user's specific code context.
4. Flag anti-patterns from the loaded reference when found in user code.

Output Format

## TDD Guidance: [phase/topic]

[Specific advice applied to user's code context]

  Pattern: [recommended approach]
  Anti-pattern: [what to avoid and why]

Reference: [which reference file was consulted]

References