Jest + React Testing Library: The Complete Practical Guide
In this video, we cover everything you need to start testing React components with Jest and React Testing Library. We build one component from scratch and use it to demonstrate every core concept: how to structure tests with describe and test blocks, the difference between getBy, queryBy, and findBy queries and exactly when to use each, how to mock entire modules with jest.mock(), how to fake prop callbacks with jest.fn(), and how jest.spyOn() differs from both. We also cover test cleanup with afterEach, mockReset, and mockRestore so your tests don't bleed into each other. By the end you'll have a complete test file covering rendering, async data loading, error states, loading states, and user interactions. What's covered: Jest basics and the Arrange, Act, Assert pattern getBy vs queryBy vs findBy, the full breakdown getByRole, getByText and when to use each jest.mock() for replacing API modules mockResolvedValue and mockRejectedValue for async jest.fn() for testing prop callbacks jest.spyOn() and when it beats jest.mock() #reacttesting #jest #webdevelopment

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