Vitest

Vitest

The fast Vite-native unit test runner for JS, TS, React, Vue, Svelte, and Node. Setup, matchers, mocking, snapshots, coverage, browser mode, workspaces, type testing, and real-world testing patterns with MSW, hooks, stores, and CI.

FundamentalsTopics 1–9
  • ·What is Vitest & why it exists
  • ·Install & project setup
  • ·Writing your first test
  • ·describe / test / it structure
  • ·expect matchers
  • ·Running tests & watch mode
  • ·The Vitest UI
  • ·Basic mocking with vi.fn() and vi.spyOn()
  • ·Configuring vitest.config.ts & TypeScript
Start Fundamentals →
IntermediateTopics 10–18
  • ·Lifecycle hooks (beforeEach / afterEach / beforeAll / afterAll)
  • ·vi.mock() for module mocking
  • ·Faking timers with vi.useFakeTimers()
  • ·Snapshot testing & inline snapshots
  • ·Testing async code & promises
  • ·Testing React with @testing-library/react
  • ·Testing Vue with @vue/test-utils
  • ·Coverage with @vitest/coverage-v8
  • ·Globals vs explicit imports
Start Intermediate →
AdvancedTopics 19–27
  • ·Vitest workspaces for monorepos
  • ·Browser mode
  • ·In-source testing
  • ·Custom matchers via expect.extend
  • ·Parallel & concurrent execution
  • ·Isolation modes (threads vs forks)
  • ·Benchmark testing with bench
  • ·Type testing with expectTypeOf
  • ·ESM vs CJS mocking & dependency injection
Start Advanced →
PatternsTopics 28–36
  • ·Testing custom React hooks
  • ·Testing a Zustand or Redux store
  • ·API client testing with MSW
  • ·Next.js server actions & route handlers
  • ·Testing Node.js CLIs
  • ·Fixture patterns & data builders
  • ·Error boundaries & edge cases
  • ·Integration testing with an in-memory database
  • ·CI integration with GitHub Actions
Start Patterns →