testing-anti-patterns

Common mocking anti-patterns include testing mock behavior instead of real dependencies, over-mocking, and creating incomplete mocks. This Skill guides developers to prevent these issues and ensure mocks accurately reflect actual dependency behavior.

To stop polluting production code, avoid adding test-only methods to production classes. This Skill discourages the practice of injecting test utilities into production code, promoting separation of test logic and production implementation.

Test suites often break during refactoring due to brittle tests that assert on mock implementations rather than actual behavior. This Skill helps identify these anti-patterns so you can write robust tests that survive code refactoring.

The best way to write effective unit tests is treating tests as an integral part of implementation rather than an afterthought. This Skill helps ensure your assertions target actual behavior and that mocks accurately reflect real dependencies.

You should avoid mocking when it leads to testing mock behavior rather than real dependency interactions, or when you lack sufficient understanding of the dependencies being mocked. This Skill guides you in identifying these constraint scenarios.