Extract Vue component instance type

ts-2.7.ts

import Vue, { VueConstructor } from "vue";

declare function extractInstance<T extends Vue>(Ctor: VueConstructor<T>): T;

const Test = Vue.extend({
  data() {
    return {
      test: 123
    };
  }
});

const test = extractInstance(Test);

ts-2.8.ts

import Vue, { VueConstructor } from "vue";

type VueInstance<T extends VueConstructor<any>> 
  = T extends VueConstructor<infer R>
  ? R
  : never;

const Test = Vue.extend({
  data() {
    return {
      test: 123
    };
  }
});

type TestType = VueInstance<typeof Test>;