Why shouldn't I add test-only methods to production classes?

Adding test-only methods pollutes the production API and can lead to dangerous side effects if those methods are accidentally called in a live environment.

Does this skill help with Test-Driven Development (TDD)?

Yes, it encourages the TDD cycle—write failing test, implement, refactor—to ensure that integration tests are built-in rather than added as an afterthought.

What happens if a mock doesn't match the real API schema?

The skill identifies incomplete mocks and requires they mirror the full real-world schema to prevent downstream failures in components that expect specific metadata or fields.

How does this skill prevent testing mock behavior?

It implements a 'Gate' that forces the developer to verify if an assertion is checking actual application logic or just confirming that a mock was called, suggesting unmocking if the latter is true.

Engineering Testing Anti-Patterns

Name: Engineering Testing Anti-Patterns
Author: tjboudreaux

bytjboudreaux

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보안 및 테스팅

Enforces high-quality testing standards by preventing mock-related errors and production code pollution during the development process.

The Engineering Testing Anti-Patterns skill acts as a rigorous guardian for your test suite within Claude Code, ensuring that tests validate real application behavior rather than the implementation details of mocks. By enforcing five 'Iron Laws,' it prevents common pitfalls such as leaking test-only methods into production code, creating incomplete mocks that don't match real schemas, and treating integration tests as an afterthought. This skill is essential for teams aiming to maintain a clean, reliable, and maintainable codebase through disciplined TDD and isolation practices.

주요 기능

01Blocks the addition of test-only methods to production classes

021 GitHub stars

03Prevents assertions on mock behavior to ensure real logic is tested

04Ensures mocks mirror full real-world API schemas

05Enforces dependency analysis before implementing mocks

06Promotes TDD workflows to improve integration test coverage

사용 사례

01Reviewing new code to ensure test helpers don't pollute the production API

02Designing high-fidelity mocks for complex external dependencies

03Refactoring brittle test suites that rely too heavily on internal mock state

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add tjboudreaux/cc-plugin-engineering-excellence eng-testing-anti-patterns

For use in Claude.ai and ChatGPT

Download Skill

주요 기능

01Blocks the addition of test-only methods to production classes

021 GitHub stars

03Prevents assertions on mock behavior to ensure real logic is tested

04Ensures mocks mirror full real-world API schemas

05Enforces dependency analysis before implementing mocks

06Promotes TDD workflows to improve integration test coverage

사용 사례

01Reviewing new code to ensure test helpers don't pollute the production API

02Designing high-fidelity mocks for complex external dependencies

03Refactoring brittle test suites that rely too heavily on internal mock state

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add tjboudreaux/cc-plugin-engineering-excellence eng-testing-anti-patterns

For use in Claude.ai and ChatGPT

Download Skill