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Mockando Endpoints com MSW em Testes com Jest e React Query
Directly mocking `useQuery` in React Query tests compromises its functionalities like caching and automatic refetch. MSW (Mock Service Worker) offers a superior approach by simulating real endpoints. Instead of mocking the hook, MSW intercepts actual requests (fetch/axios) and returns mocked responses, preserving React Query's logic. Setting up MSW involves installation, creating handlers to define mocked responses, configuring a test server, and integrating it with Jest. A practical example demonstrates testing a user list component using MSW, showcasing how to verify loading, error, and success states. Using MSW provides benefits such as testing real API integration, enabling React Query's full functionality, and facilitating easier maintenance and reuse in E2E tests. This approach ensures more reliable and maintainable tests, reflecting real-world scenarios. Mocking the endpoint instead of the hook is a best practice for robust and realistic React Query testing. This ensures tests are closer to reality, more reliable, and easier to evolve.
