Access RuntimeConfig via $config returns undefined

[marcel-wtfoxtrot]

Environment

---

• Operating System: Linux
• Node Version: v18.18.0
• Nuxt Version: 3.10.3
• CLI Version: 3.10.1
• Nitro Version: 2.9.3
• Package Manager: npm@10.2.3
• Builder: -
• User Config: devtools, runtimeConfig, modules
• Runtime Modules: @nuxt/test-utils/module@3.11.0
• Build Modules: -

---

Reproduction

https://stackblitz.com/edit/nuxt-starter-j9nscj?file=vitest.config.ts

Describe the bug

Hi there,

during Migration i came across an issue. I still have some Options API Components which are using this.$config.public to access Nuxt Runtime Config.

It seems to be working fine but whenever i run vitest i receive the following error:

TypeError: Cannot read properties of undefined (reading 'public')

An simple Workaround for this is to simply mock $config globally.
But shouldn't $config be working out of the box?

Thank you!

Additional context

No response

Logs

TypeError: Cannot read properties of undefined (reading 'public')
 ❯ Proxy.data components/withPublicConfigAccess.vue:7:26
      8| </template>
      9| 
     10| <script>
       |      ^
     11| export default {
     12|   data() {
 ❯ applyOptions node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:3460:30
 ❯ finishComponentSetup node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:7663:7
 ❯ setupStatefulComponent node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:7586:5
 ❯ setupComponent node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:7515:36
 ❯ mountComponent node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:5845:7
 ❯ processComponent node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:5811:9
 ❯ patch node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:5290:11
 ❯ ReactiveEffect.componentUpdateFn node_modules/@vue/runtime-core/dist/runtime-core.cjs.js:5955:11
 ❯ ReactiveEffect.run node_modules/@vue/reactivity/dist/reactivity.cjs.js:181:19