Type checking fails for components loaded via `defineAsyncComponent`

[BlushingTomato]

Vue - Official extension or vue-tsc version

2.1.4

VSCode version

1.92.2

Vue version

2.7.16

TypeScript version

5.5.4

System Info

No response

package.json dependencies

No response

Steps to reproduce

• Import a component via const Component = defineAsyncComponent(() => import('path/to/Component.vue')) and use it within the template.
• Run vue-tsc --noEmit
• Notice the error.

What is expected?

The check passing succesfully.

What is actually happening?

The following TS error:

TS2345: Argument of type '{}' is not assignable to parameter of type '(component: Component<DefaultData<never>, DefaultMethods<never>, DefaultComputed, DefaultProps, {}>) => void'.
  Type '{}' provides no match for the signature '(component: Component<DefaultData<never>, DefaultMethods<never>, DefaultComputed, DefaultProps, {}>): void'.

Link to minimal reproduction

No response

Any additional comments?

This issue started happening in 2.1.4, 2.1.2 seems to work fine.

[KazariEX]

I cannot reproduce it. Could you provide a minimal reproduction?

[BlushingTomato]

I tried creating a minimal reproduction, but cannot seem to reproduce it outside of our main repo 😞

I noticed that it also only happens for some components, not all of them. I'll keep looking as to what could be causing this.

[BlushingTomato]

Actually managed to reproduce it, you can see it here:

• https://github.com/BlushingTomato/vue-tsc-repro

Seems to happen on defineAsyncComponent instances which do not have any props passed.

[KazariEX]

Enter the node_modules/.vue-global-types/vue_2.7_false.d.ts file, add the following content before line 102:

    : T extends () => any ? (props: {}, ctx?: any) => ReturnType<T>
+   : T extends (...args: any) => Promise<infer R> | void ? () => R
    : T extends (...args: any) => any ? T

Could this solve your problem?

[BlushingTomato]

The vue_2.7_false.d.ts file gets reset when I run the vue-tsc --noEmit command, so it keeps happening. Can I use a flag to disable that behavior?

[KazariEX]

You can patch the @vue/language-core/lib/codegen/globalTypes.js file as a temporary solution.

[BlushingTomato]

No, the issue sadly persists even after patching the file.

[KazariEX]

It solved your repro on my machine, so I don't how to confirm the issue that occurred on your main repository :(

[BlushingTomato]

I tested it on the repro on my machine too, where it failed 🤔

I've added : T extends (...args: any) => Promise<infer R> | void ? () => R after line 124 inside codegen/globalTypes, should I add it somewhere else?

[BlushingTomato]

Oh my god, I cannot read. I've added it before that line and now it works. I apologize for the inconvenience and thank you for the solution.

[HryhoriiUstymenko]

Hello, I stumbled upon the same issue. Looking forward to it being fixed!

[KazariEX]

The current solution is not elegant and may trigger other unexpected type inferences. We are currently unable to merge it into the main branch - please use the above workaround temporarily until then.