v-if is executed even when v-for doesnt iterate anything

[Fuzzyma]

Version

3.0.0-rc.9

Reproduction link

https://codesandbox.io/s/amazing-feistel-udure?file=/src/App.vue

Steps to reproduce

Open the link and open the console.

Alternatively put an v-if on an element with v-for which iterates through an empty array and throw an error in the v-if computed property or call debugger.

What is expected?

The error should not be thrown (or the debugger statement not beeing executed)

What is actually happening?

The error is thrown

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It seems that v-if is evaluated even though v-for was passed an empty array and hence has nothing to iterate over.

The docs say, that v-for is evaluated first and that's how it was in vue 2 but somehow this behavior changed.

PS: I am aware, that for that exact reason you shouldn't use both on an element. However, it should still work!

[skirtles-code]

Related: #1165.

[posva]

See #1165 (comment)