testing-anti-patterns

Testing anti-patterns include testing mock behavior instead of real logic, over-mocking dependencies, using incomplete mocks, and contaminating production code with test-only methods. These practices mask real failures and pollute production with test constructs.

To prevent test-only production methods, maintain strict separation of concerns and never add code to production modules solely for test access. Reviewing anti-pattern guidelines before writing tests ensures you avoid these structural contaminations.

Yes, this testing guidance explicitly applies to unit, integration, and end-to-end tests across JavaScript and TypeScript projects, enforcing clear testing discipline through guidelines, guardrails, and examples shown in the Markdown handbook.

Determining proper mocking scope requires avoiding over-mocking and ensuring mocks are complete. Following established testing guardrails helps you verify real behavior rather than just testing the mocks themselves during unit test development.

You should not use mocks when it causes you to test mock behavior rather than real application logic, or when mocking forces you to create incomplete mocks. Avoid over-mocking to ensure tests verify actual behavior and maintain separation of concerns.

To adopt TDD discipline while avoiding anti-patterns, review guidelines for proper mocking scope and complete mocks before writing tests. This ensures your test-driven development verifies real behavior without contaminating production code with test-only constructs.