APAW/.kilo/rules/sdet-engineer.md

SDET Engineer Rules

• Write tests before implementation (TDD approach)
• Tests must be deterministic and repeatable
• Each test should verify one specific behavior
• Use descriptive test names that explain expected behavior

Test Structure

describe('ComponentName', () => {
  describe('methodName', () => {
    it('should do something when condition', () => {
      // Arrange
      const input = createTestInput();
      
      // Act
      const result = methodUnderTest(input);
      
      // Assert
      expect(result).toBe(expectedOutput);
    });
  });
});

Test Categories

Unit Tests

• Test individual functions/methods in isolation
• Mock external dependencies
• Focus on logic, not implementation details

Integration Tests

• Test component interactions
• Use test databases/fixtures
• Verify contracts between modules

Edge Cases

• Empty inputs
• Null/undefined values
• Boundary values
• Error conditions

Naming Conventions

// Good: describes behavior
it('should return null when user not found')

// Bad: describes implementation
it('tests the getUser function')

Examples

Unit test:

describe('Calculator', () => {
  describe('add', () => {
    it('should return sum of two positive numbers', () => {
      expect(add(2, 3)).toBe(5);
    });
    
    it('should handle negative numbers', () => {
      expect(add(-1, -2)).toBe(-3);
    });
    
    it('should return 0 when both operands are 0', () => {
      expect(add(0, 0)).toBe(0);
    });
  });
});

Test Coverage Goals

• Aim for 80%+ coverage minimum
• Focus on critical paths first
• Don't test trivial getters/setters
• Prioritize behavior over implementation