What is the recommended approach for mocking third-party libraries?

Instead of mocking libraries directly, the skill advises creating thin wrappers around them and mocking those wrappers. This simplifies test setup and improves your system's overall architecture.

How does it handle flaky tests in asynchronous code?

It implements condition-based waiting (polling) instead of arbitrary timeouts. This ensures that tests wait exactly as long as needed for a condition to be met, reducing both flakiness and execution time.

Why does it recommend table-driven tests?

Table-driven tests make it easy and inexpensive to add new test cases for success and error scenarios within a single function, ensuring exhaustive coverage with minimal boilerplate.

What is the core testing philosophy of this skill?

The skill follows the Kent C. Dodds philosophy: 'Write tests. Not too many. Mostly integration.' It focuses on testing behavior over implementation details to ensure refactoring doesn't break tests.

Writing Good Tests

Name: Writing Good Tests
Author: pbdeuchler

bypbdeuchler

0•

Security & Testing

Implements high-quality testing patterns including table-driven tests, condition-based waiting, and strategic mocking strategies.

This skill provides a comprehensive framework for writing and reviewing robust tests across multiple languages like Go and TypeScript. It prioritizes testing real behavior over implementation details, advocating for a high integration-to-unit test ratio. By enforcing table-driven test structures, condition-based polling instead of flaky timeouts, and clear boundaries between managed and unmanaged dependencies, it helps developers build reliable test suites that resist regressions and reduce CI/CD failures. It also includes specific guidance on resource cleanup and avoiding the pollution of production code with test-only logic.

Key Features

010 GitHub stars

02Standardizes table-driven test patterns for exhaustive success and error case coverage.

03Identifies and prevents testing anti-patterns like test-only methods in production code.

04Ensures test isolation through proper cleanup of long-lived resources like VMs and Kubernetes jobs.

05Defines strategic mocking boundaries by wrapping third-party libraries.

06Replaces flaky timeouts with robust, condition-based polling logic.

Use Cases

01Conducting automated code reviews to ensure mocks aren't leaking implementation details.

02Refactoring flaky test suites to eliminate race conditions and non-deterministic CI failures.

03Architecting a new test suite that balances integration confidence with unit test speed.

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add pbdeuchler/llm-plugins writing-good-tests

For use in Claude.ai and ChatGPT

Download Skill