What are the 'Iron Laws' mentioned in the skill?

The Iron Laws are: 1. NEVER test mock behavior, 2. NEVER add test-only methods to production classes, and 3. NEVER mock without understanding dependencies.

Why is 'incomplete mocking' considered an anti-pattern?

Partial mocks hide structural assumptions; if the real API returns fields that your mock lacks, downstream code may fail in production despite passing in tests. This skill enforces mirroring the complete real-world data structure.

What is the primary goal of the Testing Anti-Patterns skill?

The primary goal is to ensure tests verify real application behavior rather than the behavior of the mocks used to isolate the code, leading to more reliable and maintainable software.

How does this skill prevent production code pollution?

It identifies 'test-only' methods added to production classes and suggests moving them to dedicated test utility files, maintaining a clean production API and following the YAGNI principle.

Testing Anti-Patterns

Name: Testing Anti-Patterns
Author: franroa

byfranroa

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보안 및 테스팅

Identifies and prevents common software testing pitfalls to ensure test suites verify real behavior rather than mock implementation.

The Testing Anti-Patterns skill serves as a rigorous quality gate for your test suites, ensuring that tests remain meaningful, maintainable, and accurate. It enforces 'The Iron Laws' of testing—preventing the validation of mock behavior, stopping the pollution of production code with test-only methods, and requiring a deep understanding of dependencies before mocking. By providing actionable Gate Functions and identifying common red flags, this skill helps developers move away from brittle tests and toward a robust Test-Driven Development (TDD) workflow that captures real system logic.

주요 기능

01Enforces structural completeness for mocks to prevent silent downstream failures

02Provides guided 'Gate Functions' to evaluate whether mocking is necessary or appropriate

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04Prevents production class pollution by flagging methods used exclusively for testing

05Promotes strict TDD cycles to ensure implementation follows meaningful test failure

06Identifies and blocks assertions that verify mock existence instead of component behavior

사용 사례

01Performing code reviews to ensure production APIs remain clean and free of test-only logic

02Standardizing testing best practices across a development team using TDD principles

03Refactoring brittle test suites that break during minor implementation changes

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add franroa/chezmoi testing-anti-patterns

For use in Claude.ai and ChatGPT

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