Following documentation and using `defineVitestConfig` results in an `[ERROR] "@nuxt/test-utils/config" resolved to an ESM file.`

[ColtHands]

Environment

Local machine

• Operating System: Windows_NT
• Node Version: v18.15.0
• Nuxt Version: 3.7.1
• CLI Version: 3.8.1
• Nitro Version: 2.6.3
• Package Manager: yarn@1.22.19
• Builder: -
• User Config: app, devtools, modules, tailwindcss, css, runtimeConfig, build
• Runtime Modules: @nuxt/ui@2.12.0, @nuxtjs/tailwindcss@6.8.0, @nuxt/test-utils/module@3.9.0
• Build Modules: -

---

Stackblitz env

• Operating System: Linux
• Node Version: v18.18.0
• Nuxt Version: -
• CLI Version: 3.10.0
• Nitro Version: -
• Package Manager: npm@9.4.2
• Builder: -
• User Config: -
• Runtime Modules: -
• Build Modules: -

---

Reproduction

Repro stack blitz - https://stackblitz.com/edit/stackblitz-starters-cetpk5?file=vitest.config.js

Describe the bug

When following testing documentation - https://nuxt.com/docs/getting-started/testing, after adding vitest.config.{ts,js} with defineVitestConfig and a basic test, vitest run fails with an error

Bash error.

✘ [ERROR] "@nuxt/test-utils/config" resolved to an ESM file. ESM file cannot be loaded by `require`. See https://vitejs.dev/guide/troubleshooting.html#this-package-is-esm-only for more details. [plugin externalize-deps]

node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:68381:9:
  68381 │         }
        ╵          ^

at bundleConfigFile/setup/< (/home/projects/stackblitz-starters-cetpk5/node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:68381:35)
at handlePlugins/requestCallbacks["on-resolve"] (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:1364:28)
at handleRequest (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:722:17)
at handleIncomingPacket (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:747:20)
at readFromStdout (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:670:27)
at EventEmitter.prototype.emit (node:events:42:9202)
at addChunk (node:internal/streams/readable:105:4109)
at readableAddChunk (node:internal/streams/readable:105:3816)
at Readable.prototype.push (node:internal/streams/readable:105:2679)
at onStreamRead (node:internal/stream_base_commons:158:2341)
at _0x340f71/< (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:318835)
at _0x241289 (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:320540)
at _0x124cfc (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:317167)
at _0x574284/</< (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:319772)
at _0x574284/< (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:319750)
at _0x574284 (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:319784)

This error came from the "onResolve" callback registered here:

node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:68345:26:
  68345 │                 name: 'inject-file-scope-variables',
        ╵                           ^

at setup (/home/projects/stackblitz-starters-cetpk5/node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:68345:27)
at handlePlugins (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:1283:26)
at buildOrContextImpl (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:969:18)
at buildOrContext (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:778:23)
at build/< (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:2020:15)
at build (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:2019:25)
at build (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:1853:51)
at bundleConfigFile (/home/projects/stackblitz-starters-cetpk5/node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:68306:35)
at loadConfigFromFile (/home/projects/stackblitz-starters-cetpk5/node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:68282:31)
at resolveConfig (/home/projects/stackblitz-starters-cetpk5/node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:67884:34)
at _createServer (/home/projects/stackblitz-starters-cetpk5/node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:60373:26)
at createServer (/home/projects/stackblitz-starters-cetpk5/node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:60370:12)
at createViteServer (/home/projects/stackblitz-starters-cetpk5/node_modules/vitest/dist/vendor/node.xyYo9ZvH.js:7672:30)
at createVitest (/home/projects/stackblitz-starters-cetpk5/node_modules/vitest/dist/vendor/node.xyYo9ZvH.js:8894:24)

The plugin "externalize-deps" was triggered by this import

vitest.config.js:4:35:
  4 │ import { defineVitestConfig } from '@nuxt/test-utils/config'
    ╵                                    ~~~~~~~~~~~~~~~~~~~~~~~~~

failed to load config from /home/projects/stackblitz-starters-cetpk5/vitest.config.js

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Unhandled Error ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
Error: Build failed with 1 error:
node_modules/vite/dist/node/chunks/dep-V3BH7oO1.js:68381:9: ERROR: [plugin: externalize-deps] "@nuxt/test-utils/config" resolved to an ESM file. ESM file cannot be loaded by require. See https://vitejs.dev/guide/troubleshooting.html#this-package-is-esm-only for more details.
at failureErrorWithLog (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:1641:15)
at buildResponseToResult/< (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:1049:44)
at runOnEndCallbacks (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:1476:49)
at buildResponseToResult (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:1047:24)
at buildOrContextContinue/< (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:1076:16)
at sendRequest/responseCallbacks[id] (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:694:17)
at handleIncomingPacket (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:754:17)
at readFromStdout (/home/projects/stackblitz-starters-cetpk5/node_modules/esbuild/lib/main.js:670:27)
at EventEmitter.prototype.emit (node:events:42:9202)
at addChunk (node:internal/streams/readable:105:4109)
at readableAddChunk (node:internal/streams/readable:105:3816)
at Readable.prototype.push (node:internal/streams/readable:105:2679)
at onStreamRead (node:internal/stream_base_commons:158:2341)
at _0x340f71/< (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:318835)
at _0x241289 (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:320540)
at _0x124cfc (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:317167)
at _0x574284/</< (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:319772)
at _0x574284/< (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:319750)
at _0x574284 (https://stackblitzstarterscetpk5-klbu.w-corp.staticblitz.com/blitz.f7aa08df.js:350:319784) {
errors: [Getter/Setter],
warnings: [Getter/Setter]
}

If there's something im doing wrong (eg Node version, some extra setup) this should be stated in the docs

Additional context

Sry if dupe, couldn't find a similar issue

Logs

No response

[danielroe]

This isn't Nuxt specific here, but to import @nuxt/test-utils in your vitest config, you either need to have to have type: "module" specified in your package.json or name it vitest.config.m{ts,js}.

We should make this clear in the docs.

[cory-baker]

getting the same thing but renaming to .cts did not work

[cory-baker]

update: renaming to .mts did work

[danielroe]

do you not have type: module in your package.json?

https://github.com/nuxt/starter/blob/v3/package.json#L4