How does this skill prevent production code pollution?

It identifies methods intended only for testing and provides guidance on moving them to external test-utility files, keeping production classes focused on business logic.

What are the Iron Laws of testing mentioned in this skill?

The Iron Laws are: NEVER test mock behavior, NEVER add test-only methods to production classes, and NEVER mock without fully understanding the underlying dependencies.

Why is 'testing mock behavior' considered an anti-pattern?

Testing mock behavior only verifies that your mock works, not that your application works. This leads to tests that pass even when the real component is broken.

How does this skill handle incomplete mocks?

It enforces a rule to mirror the complete real-world data structure. Partial mocks are flagged because they hide structural assumptions and lead to silent failures in downstream code.

Testing Anti-Patterns Guard

Name: Testing Anti-Patterns Guard
Author: cipherstash

bycipherstash

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セキュリティとテスト

Enforces robust software testing standards by identifying and preventing brittle mocks, production code pollution, and incomplete test data structures.

The Testing Anti-Patterns skill acts as a guardrail for your quality assurance process, ensuring that tests verify real application behavior rather than the behavior of mocks. It implements the 'Iron Laws' of testing to prevent the common pitfalls of TDD, such as adding test-only methods to production classes or mocking dependencies without a full understanding of their side effects. By utilizing specialized 'Gate Functions,' this skill helps developers maintain a clean separation between production logic and test utilities while ensuring that every mock mirrors reality with structural completeness.

主な機能

01Identifies and blocks the addition of test-only methods to production classes

02Prevents assertions on mock existence to focus on real component behavior

03Provides Gate Functions to validate testing strategies before implementation

044 GitHub stars

05Enforces structural completeness for mocks to prevent silent downstream failures

06Promotes strict TDD cycles to ensure tests are meaningful and reliable

ユースケース

01Onboarding developers to high-standard TDD environments with automated best-practice guidance

02Sanitizing production codebases by migrating test-specific logic to external utility helpers

03Refactoring brittle test suites that fail due to implementation details rather than logic errors

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add cipherstash/cipherpowers testing-anti-patterns

For use in Claude.ai and ChatGPT

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