React · Senior · Question 62 of 75

Why mock network requests with Mock Service Worker (MSW) rather than mocking `fetch` in each test?

✓Correct answer: MSW intercepts requests at the network level, so components use their real data layer and the same handlers work in tests and dev
2MSW makes requests faster
3Mocking fetch is impossible in Jest/Vitest

Explanation

Tests stay closer to real usage and don't break when you switch from fetch to a library. Handlers can be overridden per test for error cases.

Further reading

Mock Service Worker: Docs ↗

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