Vitest
Next generation testing framework powered by Vite.
Documentation | Getting Started | Examples | Why Vitest?
## Features - [Vite](https://vitejs.dev/)'s config, transformers, resolvers, and plugins. Use the same setup from your app! - [Jest Snapshot](https://jestjs.io/docs/snapshot-testing) - [Chai](https://www.chaijs.com/) built-in for assertions, with [Jest expect](https://jestjs.io/docs/expect) compatible APIs - [Smart & instant watch mode](https://vitest.dev/guide/features.html#watch-mode), like HMR for tests! - [Native code coverage](https://vitest.dev/guide/features.html#coverage) via [`v8`](https://v8.dev/blog/javascript-code-coverage) or [`istanbul`](https://istanbul.js.org/). - [Tinyspy](https://github.com/tinylibs/tinyspy) built-in for mocking, stubbing, and spies. - [JSDOM](https://github.com/jsdom/jsdom) and [happy-dom](https://github.com/capricorn86/happy-dom) for DOM and browser API mocking - Components testing ([Vue](./examples/vue), [React](./examples/react), [Svelte](./examples/svelte), [Lit](./examples/lit), [Vitesse](./examples/vitesse), [Marko](https://github.com/marko-js/examples/tree/master/examples/library-ts)) - Workers multi-threading via [Tinypool](https://github.com/tinylibs/tinypool) (a lightweight fork of [Piscina](https://github.com/piscinajs/piscina)) - Benchmarking support with [Tinybench](https://github.com/tinylibs/tinybench) - [Workspace](https://vitest.dev/guide/workspace) support - [expect-type](https://github.com/mmkal/expect-type) for type-level testing - ESM first, top level await - Out-of-box TypeScript / JSX support - Filtering, timeouts, concurrent for suite and tests - Sharding support > Vitest 1.0 requires Vite >=v5.0.0 and Node >=v18.0.0 ```ts import { assert, describe, expect, it } from 'vitest' describe('suite name', () => { it('foo', () => { expect(1 + 1).toEqual(2) expect(true).to.be.true }) it('bar', () => { assert.equal(Math.sqrt(4), 2) }) it('snapshot', () => { expect({ foo: 'bar' }).toMatchSnapshot() }) }) ``` ```bash $ npx vitest ``` ## Sponsors ### Vladimir Sponsors
