Version

3.1.4

Reproduction link

https://sfc.vuejs.org/#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

Steps to reproduce

when use createApp in setup, inject will get undefined.

What is expected?

get correct value

What is actually happening?

can not get correct value

maybe this is expected. but we have some Scenes use api component, like window.alert. Now, ant-design-vue, element-plus all use createApp to create new instance. Do you have some recommend， If we can not use createApp in setup.

This is expected, it's even used at https://github.com/vueuse/vueuse/blob/main/packages/core/createGlobalState/index.ts) until effectScope() is released.

You need to move any provide/inject inside setup() before any createApp call. You shouldn't call createApp() inside of a Vue component either

BTW your reproduction is very far from minimal and it's difficult to navigate

@posva sorry, I change new reproduction. can you review this issue again? thank you very much

Yeah, thanks! So, it's what I said before: the inject should happen before the createApp()

This is not friendly for user, and we have no way to judge whether there is a createApp before inject

I cannot give some warning.

@userquin thanks. I know we should use createApp after inject.

But If we develop some components for everyone. Our compoennts cannot give warning to user.

Maybe we can give tips you cannot use xxx after inject at doc. But user donot know useRouter useStore ...... was implemented by inject.