React projects use several popular libraries to make testing efficient, reliable, and developer-friendly. Here are the top ones:

1. Jest

   • A powerful JavaScript testing framework developed by Meta (formerly Facebook).
   • Provides test runners, assertion libraries, mocks, and spies — all in one package.
   • Great for unit tests, integration tests, and snapshot tests.

2. React Testing Library (RTL)

   • Focuses on testing components from the user’s perspective (interacting with DOM elements).
   • Encourages best practices like avoiding testing component internals and focusing on user behavior.

3. Enzyme (less popular today)

   • Created by Airbnb to test React components.
   • Offers utilities for shallow rendering, mounting, and manipulating React components.
   • Still used in some legacy codebases but increasingly replaced by RTL.

4. Cypress

   • Primarily for end-to-end (E2E) testing.
   • Simulates real user interactions in the browser, testing full app workflows.

5. Playwright / Puppeteer

   • Used for automated browser testing and E2E scenarios.
   • Useful when complex user journeys or multi-tab/page behaviors need to be tested.

Choosing the right library depends on the type of testing needed — unit, integration, or end-to-end.

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