vitest

Run Jest-compatible unit and integration tests for Vite projects.

2|Updated May 5, 2023

Search Tags:#vitest #testing #javascript #vite #mocking #unit-testing #testing-framework

Ready to run

npx skills add https://github.com/baicie/template-repo --skill vitest-baicie

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: vitest
Source: https://github.com/baicie/template-repo/tree/main/monorepo/.agents/skills/vitest
Command: npx skills add https://github.com/baicie/template-repo --skill vitest-baicie

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

Vitest provides a fast, Jest-compatible testing framework for Vite projects, simplifying test setup, execution, and parallel workflow across modern frontend stacks.

Core Features & Use Cases

Unit and integration testing for Vite-based projects
Mocking with vi.fn and vi.mock, timers, and coverage thresholds
Parallel test execution and browser/environment support (node/jsdom)

Quick Start

Install Vitest in your project and start writing tests with describe/it, using vi.fn and vi.mock for mocks.

Frequently Asked Questions about vitest

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I set up unit testing for a Vite project?▼

Vitest provides a fast, Jest-compatible testing framework for Vite projects. It uses your existing vite.config.ts or vitest.config.ts for setup and allows you to write tests using familiar describe and it blocks.

Can I use Vitest for testing Vue, React, and Svelte components?▼

Vitest supports unit and integration testing across Vue, React, and Svelte components. It leverages the Vite pipeline to process and test these frontend components efficiently.

How do I create mocks and control timers in Vitest?▼

You can create mocks and control timers in Vitest using the built-in vi.fn and vi.mock utilities. These tools allow you to mock dependencies and manipulate timers for isolated unit testing.

Does Vitest support parallel test execution and code coverage?▼

Vitest supports parallel test execution and code coverage thresholds. It executes tests concurrently to maximize speed and provides built-in coverage reporting for your Vite project.

What is the best way to migrate from Jest to Vitest?▼

Migrating from Jest to Vitest is straightforward because Vitest provides a Jest-compatible API. You can transition your tests to Vite's pipeline for faster execution without major rewrites.

Do I need a specific configuration file to run Vitest?▼

Vitest requires a vitest.config.ts or vite.config.ts file to run. The framework uses frontmatter for test discovery and relies on this configuration to define environments like node or jsdom.