Bug: type errors while using SFC script setup

[Oleksii14]

Describe the bug
While using two top-level script blocks in SFC, there appear TS errors in the console after vite build that go from @vue/test-utils typings. Those errors depend on the trailing coma from the first script block.

To Reproduce
Reproduction repo
Steps:

pnpm i

pnpm run test:unit # test will pass

pnpm run build # will fail, see the type errors

Then go to HelloWorld.vue and remove a trailing comma in line 4.
Perform the steps above and the build error will dissapear.

Expected behavior
Type errors do not appear and do not depend on the trailing comma in the top-level script

Related information:

• @vue/test-utils version: 2.0.0-rc.18
• Vue version: 3.2.26
• node version: 14.17.6
• pnpm version: 6.25.1

Additional context

[lmiller1990]

I don't understand your comment around the trailing comma. Line 4 does not have one: https://github.com/Oleksii14/vue-jest-type-issue/blob/888e76c5276fda9509ba5b87121fb34c1fb44523/src/components/HelloWorld.vue#L4

I see this issue. I was able to get it to work by adding export default defineComponent to the first script tag:

<script lang="ts">
import { defineComponent } from 'vue';

export default defineComponent({
  inheritAttrs: false
})
</script>

[Oleksii14]

Sorry, I meant semicolon.

Thanks for the reply, but I need it to work without defineComponent using the setup script.

According to my comment, TS errors disappear at once after I remove the semicolon. Why is that happening?

[cexbrayat]

This is super strange indeed. I don't think this is an issue with VTU though, it might be an issue of vue-tsc.

You should try to open this issue on the Volar repo, and link back to it so we can track it.

[lmiller1990]

Looks like it is fixed: vuejs/language-tools#874