testing-anti-patterns

# Testing Anti-Patterns You are identifying and avoiding common testing anti-patterns. ## Review Workflow Follow these steps when reviewing test code: 1. **Run tests in isolation** — Verify each test passes independently (no shared state, no ordering dependency). 2. **Check for patterns below** — Scan for each anti-pattern in the checklist; flag every match with the specific defect. 3. **Apply refactoring strategy** — Use the refactoring strategies section to select and apply the appropriate fix. 4. **Verify the test still fails when code breaks** — After fixing, confirm the corrected test catches real regressions (remove or stub the implementation to confirm a failure occurs). ## Critical Anti-Patterns ### 1. The Liar - Tests That Always Pass **Problem:** Test passes even when the code is broken. ```typescript // BAD - Always passes because it tests nothing meaningful it('should process data', () => { const result = processData(input); expect(result).toBeDefined(); // Too weak }); // GOOD - Actually verifies behavior it('should transform input to uppercase', () => { const result = processData({ text: 'hello' }); expect(result.text).toBe('HELLO'); }); ``` **Detection:** Remove or break the implementation - test should fail. ### 2. The Giant - Tests Too Large **Problem:** Single test covers too many behaviors. ```typescript // BAD - Tests multiple things it('should handle user registration', async () => { const user = await register(userData); expect(u...