Vitest

Run Vitest unit, integration, and React component tests with mocking and coverage analysis.

Updated Dec 30, 2025
One-click install
npx skills add https://github.com/vietlinhh02/cogninote --skill vitest-vietlinhh02
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: Vitest
Source: https://github.com/vietlinhh02/cogninote/tree/main/.claude/skills/testing/vitest
Command: npx skills add https://github.com/vietlinhh02/cogninote --skill vitest-vietlinhh02

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This Skill provides a robust framework for testing JavaScript and TypeScript code, enabling developers to ensure code quality, catch bugs early, and maintain confidence in their applications.

Core Features & Use Cases

  • Unit and Integration Testing: Write comprehensive tests for individual functions, modules, or integrated components.
  • Mocking: Easily mock modules and functions to isolate units under test and control dependencies.
  • React Component Testing: Specialized support for testing React components, including user interactions.
  • Use Case: You've just refactored a critical utility function. Use Vitest to write a suite of tests that verify its behavior with various inputs, ensuring the refactor didn't introduce regressions.

Quick Start

Use the vitest skill to run all tests in the project.

Frequently Asked Questions about Vitest

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

FAQPage Schema
How do I write unit tests for TypeScript and JavaScript using Vitest?

Writing unit tests for TypeScript and JavaScript with Vitest involves creating test suites that verify individual functions and modules. This requires a Node.js environment with Vitest installed to execute the tests and verify code functionality.

What is the best way to test React components and user interactions?

Testing React components and user interactions is handled through Vitest's specialized support for React component testing. This allows you to verify component behavior and simulate user interactions within your test suites.

How do I mock modules and dependencies in JavaScript testing?

Mocking modules and dependencies in JavaScript testing is facilitated by Vitest's mocking capabilities. You can easily mock modules and functions to isolate the units under test and control external dependencies during execution.

Does Vitest support code coverage analysis for TypeScript projects?

Yes, Vitest supports code coverage analysis for TypeScript projects. This capability allows you to analyze code coverage alongside running unit, integration, and React component tests to ensure code quality and catch bugs early.

Do I need a specific environment to run Vitest test suites?

You need a Node.js environment with Vitest installed to run test suites. This environment is required to execute the tests, verify code functionality, and utilize features like mocking and code coverage analysis.

What's the best way to prevent regressions when refactoring utility functions?

Preventing regressions when refactoring utility functions is best achieved by using Vitest to write a suite of tests verifying behavior with various inputs. This ensures your refactor maintains confidence in your application and catches bugs early.