testing-ruleslisted

# Testing Rules These rules are mandatory for all test-related work. ## TDD Workflow RED → GREEN → REFACTOR (all new code). ## Test Strategy | Layer | Test Type | Mock Strategy | |-------|-----------|---------------| | Functional Core | Unit Test | No mocks needed (pure input→output) | | Imperative Shell | Integration | Testcontainers (real DB/services) | | External APIs | Test Double | With `// Test Double rationale: [reason]` | ## Forbidden Patterns These patterns are **never** acceptable: | Pattern | Why Forbidden | Alternative | |---------|---------------|-------------| | `jest.fn()` for Repository/Service/Domain | Invalid test — doesn't prove production works | Testcontainers | | `class InMemoryRepository` | Diverges from real DB behavior | Real DB container | | `class MockXxx` / `class FakeXxx` | Hides integration issues | Direct instantiation or Testcontainers | | `jest.mock('../services/X')` | Skips real collaboration | Test real collaboration | | `it.skip('...database...')` | "Too slow" is not valid | Testcontainers are fast enough | ## Coverage Requirements - 80% overall minimum - 100% Functional Core (pure logic must be fully tested) - Critical paths for Imperative Shell ## Dev/Prod Parity Tests must use real dependencies: - Real database via Testcontainers (not in-memory substitutes) - Config via environment variables - Mock tests passing ≠ production working ## Detection Checklist When analyzing test files, flag: 1. Any `jest.fn()` usage on Reposito