testing-anti-patterns

Testing mock behavior validates the mock itself rather than production logic. This Skill detects when tests verify mock calls or responses instead of actual system behavior, guiding you to refactor tests to exercise real dependencies and assert on genuine outcomes.

Test-only production methods create hidden APIs, inflate surface area, and couple production to test concerns. This Skill identifies such methods and enforces production cleanliness by requiring tests to work with public APIs only.

Mocking is appropriate only when dependencies are fully understood and external. This Skill enforces integration hygiene by checking that mocks are applied deliberately, not reflexively, preventing shallow test suites that miss real integration failures.

Yes. This Skill detects anti-patterns in TypeScript and JavaScript tests, including mock abuse, test-only production code, and incomplete dependency understanding across both ecosystems.

Testing mocks verifies that your mock was called correctly—a tautology that breaks when real dependencies behave differently. Testing real behavior validates that your code works with actual systems, catching integration bugs mocks hide.

Review your test for mock verification statements, test-only helper methods in production files, and mocks of internal or insufficiently understood dependencies. This Skill applies gate-style checks during test review or modification to flag and guide refactoring of these issues.