---
name: vitest-85722232e303
description: A blazing fast unit testing framework powered by Vite
license: MIT
---

# Vitest

Vite-native testing framework with Jest-compatible API.

## When to Use

- Writing unit/integration tests for Vite projects
- Testing Vue/React/Svelte components
- Mocking modules, timers, or dates
- Running concurrent/parallel tests
- Type testing with TypeScript

## Quick Start

```bash
npm i -D vitest
```

```ts
// vitest.config.ts
import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    globals: true,
    environment: 'node',  // or 'jsdom' for DOM tests
  },
})
```

```ts
// example.test.ts
import { describe, expect, it, vi } from 'vitest'

describe('math', () => {
  it('adds numbers', () => {
    expect(1 + 1).toBe(2)
  })
})
```

## Reference Files

| Task                                     | File                                    |
| ---------------------------------------- | --------------------------------------- |
| Configuration, CLI, projects             | [config.md](references/config.md)       |
| test/describe, hooks, fixtures           | [test-api.md](references/test-api.md)   |
| vi.fn, vi.mock, timers, spies            | [mocking.md](references/mocking.md)     |
| expect, snapshots, coverage, filtering   | [utilities.md](references/utilities.md) |
| Environments, type testing, browser mode | [advanced.md](references/advanced.md)   |

## Loading Files

**Consider loading these reference files based on your task:**

- [ ] [references/config.md](references/config.md) - if setting up vitest.config.ts, CLI, or workspace projects
- [ ] [references/test-api.md](references/test-api.md) - if writing test/describe blocks, using hooks, or test fixtures
- [ ] [references/mocking.md](references/mocking.md) - if mocking modules, timers, dates, or using spies
- [ ] [references/utilities.md](references/utilities.md) - if writing assertions, snapshots, or configuring coverage
- [ ] [references/advanced.md](references/advanced.md) - if configuring test environments, type testing, or browser mode

**DO NOT load all files at once.** Load only what's relevant to your current task.

## Cross-Skill References

- **Vue component testing** → Use `vue` skill for component patterns
- **Library testing** → Use `ts-library` skill for library patterns
- **Vite configuration** → Use `vite` skill for shared config


---
Source attribution: Kurrawong
Original project: https://github.com/Kurrawong/prez-lite/blob/d1b51f4cfc75142c6eeddd9a90aae9298126e3e6/.claude/skills/vitest/SKILL.md
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Mega AI Hub.

## Upstream license notice

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.



# Mega AI Hub resource metadata

Creator / publisher: Kurrawong
Original project: https://github.com/Kurrawong/prez-lite/blob/d1b51f4cfc75142c6eeddd9a90aae9298126e3e6/.claude/skills/vitest/SKILL.md
Attribution basis: Source repository record

Fields of work: Development & Engineering
Roles: QA / Test Engineer, Frontend Developer, Backend Developer
Specialties: Testing, Cross Platform
Tools: Vite
Country applicability: Country not specified
Classification basis: Source category, role and specialization labels
Instruction SHA-256: 223528f3e1e182f7233bc2b3b4c69f55d268263c37c719f17fe498b0b0ecb07e