Glossary term
What is mock? Meaning for developers
In Full-Stack Questions
A fake stand-in for a real part of the system, used in a test.
Learn it properly · Full-Stack QuestionsLesson 21: Testing Tools: Jest, Vitest, Testing Library, PlaywrightMocks and fake timers, MSW, user-event, testing hooks and Server Components, Playwright locators and flaky tests, database tests with Prisma.In Testing From Zero
A test double that also records how it was called, so the test can check the calls.
Learn it properly · Testing From ZeroLesson 1: Unit Tests and Test DoublesArrange-act-assert, stubs, mocks, spies and fakes, fake timers, async errors, test isolation, and why mocking your own internals hurts.