GenericInstanceType

Extract the public instance type from a generic Vue component — solves the limitation where `InstanceType<typeof Component>` returns `any` for generic SFCs.

Vue's InstanceType<typeof Component> does not work on generic components (<script setup lang="ts" generic="T">). GenericInstanceType walks the type to recover the exposed methods/refs typing.

See the underlying TypeScript / Vue Language Tools issue: vuejs/language-tools#3206.

Usage

import type { GenericInstanceType } from '@maz-ui/utils'
import { ref } from 'vue'
import MyGenericList from './MyGenericList.vue'

const listRef = ref<GenericInstanceType<typeof MyGenericList> | null>(null)

// listRef.value.focus() is fully typed

API

type GenericInstanceType<T> = T extends new (...args: any[]) => infer R
  ? R
  : T extends (...args: any[]) => infer R
    ? R extends { __ctx?: infer K }
      ? Exclude<K, void> extends { expose: (...args: infer Y) => void }
        ? Y[0] & InstanceType<DefineComponent>
        : any
      : any
    : any

Notes

• Use this only for generic components. For non-generic SFCs, plain InstanceType<typeof Component> already works and is clearer.