jest-to-vitest

Name: jest-to-vitest-gaibianshiji codemod
Availability: InStock

Automated codemod for migrating Jest test suites to Vitest.

What it does

This codemod automates ~95% of the deterministic migration patterns from Jest to Vitest:

jest → vi global: jest.fn()→vi.fn(), jest.mock()→vi.mock(), jest.spyOn()→vi.spyOn()
Mock management: jest.clearAllMocks()→vi.clearAllMocks(), jest.resetAllMocks()→vi.resetAllMocks()
Timer functions: jest.useFakeTimers()→vi.useFakeTimers(), jest.advanceTimersByTime()→vi.advanceTimersByTime()
Import updates: @jest/globals→vitest, { jest }→{ vi }
Config migration: jest.config.js→vitest.config.ts with defineConfig
Auto-import injection: Automatically adds import { vi } from 'vitest' when needed

bash

Or run the migration script directly:

bash

These patterns require semantic understanding and should be handled manually:

bash

See CASE_STUDY.md for the full migration analysis of React Testing Library.

The codemod uses word-boundary-scoped regex transforms to ensure zero false positives:

All jest.* calls are replaced with vi.* equivalents using \b word boundaries
Import sources are updated (@jest/globals→vitest)
Import destructuring is updated ({ jest }→{ vi })
Auto-import injection adds import { vi } from 'vitest' when vi.* is used