Testing Skill

Testing Skill

Loaded by: QA Division agents | Version: 1.0

Test Pyramid

        /  E2E  \        <- Few, slow, expensive
       / Integr. \      <- Some, moderate
      /   Unit    \     <- Many, fast, cheap

Unit Test Pattern (Arrange, Act, Assert)

def test_user_creation():
    # Arrange
    user_data = {"name": "Alice", "email": "[email protected]"}
    # Act
    user = UserService.create(user_data)
    # Assert
    assert user.name == "Alice"
    assert user.id is not None

Coverage: 80% minimum, 100% on critical paths

Naming: test_[unit]_[scenario]_[expected_result]

Mocking

• Mock external services, not the thing under test
• Prefer dependency injection over monkey patching

Anti-Patterns

• Tests dependent on execution order or external services
• Tests without assertions; flaky timing-dependent tests
• Testing implementation instead of behavior

Checklist

• All public APIs have tests
• Edge cases covered
• Tests are independent and deterministic
• Coverage above 80%
• Test names describe behavior