Bug: Type-check doesn't work properly for variables declared in script setup components

[gbyesiltas]

Describe the bug
Trying to access a variable declared in a component written with script setup results in a type error

Property 'someVariable' does not exist on type '{ $: ComponentInternalInstance; $data: {}; $props: Partial<{ errors: string[]; }> & Omit<Readonly<ExtractPropTypes<{ action: { type: PropType<"Update" | "Create">; required: true; }; ... 5 more ...; isLoading: { ...; }; }>> & ... 5 more ... & ComponentCustomProps, "errors">; ... 10 more ...; $watch<T extends string ...'.

To Reproduce

1. Create a component with script setup and declare a variable inside it
2. Write a test where you are trying to access that variable with wrapper.vm.someVariable
3. The type-check will give an error similar to the one above

Expected behavior
The variable accesses to work without typing errors

Related information:

• @vue/test-utils version: 2.2.3
• Vue version: 3.2.45
• node version: 16.17.0
• npm (or yarn) version: 9.1.1

Additional context
The tests do pass, but typescript isn't happy

[cexbrayat]

Hi @gbyesiltas

Yes, you'll need to add an explicit cast, like expect((wrapper.vm as unknown as { count: number }).count).toBe(1).

We sadly can't do anything about it in VTU, we're waiting for improvements in Vue itself.

This is tracked in #972

Closing this one as duplicate

[gbyesiltas]

Hi @gbyesiltas

Yes, you'll need to add an explicit cast, like expect((wrapper.vm as unknown as { count: number }).count).toBe(1).

We sadly can't do anything about it in VTU, we're waiting for improvements in Vue itself.

This is tracked in #972

Closing this one as duplicate

Hey, thanks for the quick reply 👍 Won't be the prettiest thing but It will do :) Hope Vue can improve support in the future.

Also, another question, this only started happening after we made the upgrades vue: 3.2.41 --> 3.2.45 and @vue/test-utils: 2.0.0 --> 2.2.3. Is it then related to some changes that happened in the Vue side?

[cexbrayat]

Yeah I hope too 😉

This is the case for a while, but if you were still on VTU v2.0.0, maybe we had a any type for vm, whereas we now try to infer the maximum information we can (but I don't exactly remember in which version we started to improve this).

[gbyesiltas]

Thanks! :)