Vitest Setup for Svelte Projects
Configure Vitest with the Svelte plugin and jsdom environment for component testing.
Vitest Setup for Svelte Projects is a free Sveltejs Academy lesson on CoddyKit — lesson 1 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Sveltejs Academy learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Vitest
Vitest is a fast, Vite-native test runner widely used in the Svelte ecosystem.
Install
Add Vitest and the Svelte plugin.
npm install -D vitest @vitest/coverage-v8 @testing-library/svelte @testing-library/jest-dom jsdomConfig in vite.config.js
Add a test section.
export default defineConfig({
plugins: [sveltekit()],
test: { environment: "jsdom", globals: true, setupFiles: ["./vitest-setup.js"] }
});Setup File
Import jest-dom matchers in vitest-setup.js.
import "@testing-library/jest-dom";Run Tests
Add a script to package.json and run.
"test": "vitest"Watch Mode
Vitest defaults to watch mode; perfect for TDD.
TypeScript
Vitest supports TypeScript out of the box with type-aware assertions.
Coverage
Generate coverage reports with the V8 coverage provider.
npx vitest run --coverageCI Integration
Use vitest run (non-watch) in CI for predictable runs.
Snapshot Testing
Vitest supports snapshots like Jest for regression detection.
IDE Integration
VS Code's Vitest extension lets you run tests inline with editor commands.
Quick Check
What environment does Vitest use for DOM tests?
Recap
Set up Vitest with jsdom, Testing Library, and jest-dom for fast Svelte component unit tests.
Frequently asked questions
Is the “Vitest Setup for Svelte Projects” lesson free?
Yes — the full text of “Vitest Setup for Svelte Projects” is free to read here on the web, and the Sveltejs Academy course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Sveltejs Academy course, upgrade to CoddyKit PRO.
What will I learn in “Vitest Setup for Svelte Projects”?
Configure Vitest with the Svelte plugin and jsdom environment for component testing. You practise Sveltejs Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Sveltejs Academy?
No prior experience is required. Sveltejs Academy on CoddyKit is structured for beginners through advanced learners; this is — lesson 1 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Vitest Setup for Svelte Projects” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Sveltejs Academy lesson?
Yes. Every Sveltejs Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- Vitest Setup for Svelte Projects
- @testing-library/svelte: render and fireEvent
- Testing Stores and Reactivity
- Mocking Modules and Fetch