How do I run the tests once they are generated?

The skill includes CLI commands for running specific test files, enabling watch mode for TDD, and generating comprehensive coverage reports.

Can I use this for both frontend and backend testing?

Yes, the Vitest and MSW patterns provided are designed to work seamlessly across Node.js backend services and browser-based frontend applications.

How does MSW help with testing?

MSW intercepts network requests at the library level, allowing you to mock API responses realistically without manually overriding fetch or axios.

Does this skill support Jest?

While many patterns are similar, this skill specifically prioritizes Vitest for its performance and native TypeScript support.

Does it provide type safety for mocks?

Absolutely. It utilizes Vitest's vi.mocked utility to ensure your mock objects and return values strictly adhere to your TypeScript interfaces.

TypeScript Testing Patterns

Name: TypeScript Testing Patterns
Author: martinffx

bymartinffx

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Security & Testing

Implements high-quality TypeScript testing workflows using Vitest and MSW for type-safe unit, integration, and snapshot testing.

This skill provides a comprehensive framework for writing robust TypeScript tests within the Claude Code environment. It automates the setup of Vitest for unit testing and MSW for network-level API mocking, ensuring that your application logic is verified with full type safety. By offering standardized patterns for dependency injection, snapshot validation of complex objects, and asynchronous execution handling, it helps developers maintain high code quality and prevent regressions in modern TypeScript projects.

Key Features

016 GitHub stars

02Network-level API simulation using MSW (Mock Service Worker)

03Advanced async testing patterns including fake timers and promises

04Standardized test organization with shared setup and teardown logic

05Snapshot testing for complex object and UI output validation

06Type-safe mocking with Vitest and vi.mocked utility

Use Cases

01Testing complex API interactions without hitting live backend services

02Migrating legacy test suites to Vitest and MSW for better performance

03Implementing type-safe dependency injection mocks for isolated unit tests

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add martinffx/claude-code-atelier atelier-typescript-testing

For use in Claude.ai and ChatGPT

Download Skill