[vite:vue] MagicString is not a constructor

[danekslama]

Environment

Operating system	Linux 6.6.87.2-microsoft-standard-WSL2
CPU	AMD Ryzen 9 6900HX with Radeon Graphics (16 cores)
Node.js version	v24.14.1
nuxt/cli version	3.35.1
Package manager	pnpm@10.33.0
Nuxt version	4.4.4
Nitro version	2.13.4
Builder	vite@7.3.3
Config	app, compatibilityDate, css, devtools, eslint, googleFonts, modules, ogImage, runtimeConfig, security, shadcn, vite
Modules	@nuxt/icon@2.2.1, @nuxt/eslint@1.15.2, @nuxt/image@2.0.0, @nuxt/test-utils/module@4.0.3, @nuxtjs/google-fonts@3.2.0, @nuxtjs/seo@3.4.0, @vueuse/nuxt@14.2.1, @pinia/nuxt@0.11.3, nuxt-security@2.5.1, reka-ui/nuxt@2.9.1, shadcn-nuxt@2.4.3

Reproduction

https://stackblitz.com/edit/github-wjqrqsms?file=test%2Fnuxt%2Fapp.spec.ts,vitest.config.ts,nuxt.config.ts

Describe the bug

I'm getting a 'MagicString is not a constructor' error when calling the setup function inside a test. I haven't been able to run the integration tests for our simple login. Am I doing something wrong? I also tested this in a minimal reproduction on StackBlitz, and it throws the same exception.

import { $fetch, setup } from '@nuxt/test-utils'

import { describe, expect, it } from 'vitest'

describe('Family Tree Integration Tests', async() => {
  let token: string

  await setup({
    server: true
  })

  it('should login and get a token', async() => {
  .....
  })
})

Additional context

No response

Logs

[yamachi4416]

Please check the issue linked below.
nuxt/nuxt#34645

[danekslama]

Oh, so this can't work inside the Nuxt environment, right? It can be a little confusing. I should have used a standard Node environment for this. I guess it can be closed then.

import { setup } from '@nuxt/test-utils/e2e'
import { describe } from 'vitest'

describe('Login API integration test', async() => {
  await setup({
    server: true
  })
})``

[yamachi4416]

​Glad if it worked as expected in a standard Node environment.
​Agreed that it's a bit confusing, so we might do something about it. Thank you for the report🙏