vitest

# Vitest Skill Expert assistance for unit and integration testing with Vitest. ## Capabilities - Configure Vitest for projects - Write unit and integration tests - Implement mocking strategies - Configure coverage reporting - Optimize test performance ## Test Patterns ```typescript import { describe, it, expect, vi, beforeEach } from 'vitest'; import { render, screen } from '@testing-library/react'; import { UserService } from './user.service'; describe('UserService', () => { const mockDb = { user: { findMany: vi.fn() } }; beforeEach(() => { vi.clearAllMocks(); }); it('should fetch users', async () => { mockDb.user.findMany.mockResolvedValue([{ id: '1', name: 'John' }]); const service = new UserService(mockDb); const users = await service.findAll(); expect(users).toHaveLength(1); expect(mockDb.user.findMany).toHaveBeenCalledOnce(); }); }); ``` ## Configuration ```typescript // vitest.config.ts export default defineConfig({ test: { globals: true, environment: 'jsdom', coverage: { provider: 'v8', reporter: ['text', 'html'], }, }, }); ``` ## Target Processes - unit-testing - react-testing - tdd-development