Vue + typescript - TypeError: Object prototype may only be an Object or null: undefined

Question

TypeError: Object prototype may only be an Object or null: undefined

I got some error in my project. I\'m using vuejs, typescript and jest.

It\'s just simp

Answer 1

For me, using import * as Vue from "vue" instead of import Vue from "vue" fixed the problem for my projects with a similar setup, i.e.:

//import Vue from "vue";
import * as Vue from "vue";
import Component from "vue-class-component";

interface HelloWorldInterface {
  msg: string;
  clickHandler(): void;
}

@Component
export default class HelloWorld extends Vue implements HelloWorldInterface {
  msg = "Hello!!";
  clickHandler() {
    window.alert(this.msg);
  }
}

It is a lot more cumbersome, but at least it works. I have setup a proof-of-concept example using vue-cli: https://codesandbox.io/s/mjvjw2xw39