How to use data from export component in class?

I got a class, that was defined in the same Component File, but out of scope for the data, that i am exporting. I'd like to simply call the function, that was defined inside the "export default", but as i am doing, I'm getting the following error, as the map function is not inside the scope:

Test.vue?t=1751457112648:55 Uncaught TypeError: this.map is not a function` -

That is the file i am working with:

<template>
</template>
<script>
class SimpleTest {
  pong() {this.map();}
}
export default {
  name: 'Test',
  data() {
    return {
      init: false,
    }
  },
  methods: {
    map() {return "Simple Return";},
  },
  mounted() {
    let simpleOne = new SimpleTest();
    simpleOne.pong();
  }
}
</script>

Accessing a scope outside a class suggests there's a potential problem with class design. This could be written in several different ways.

This would be a quickfix that doesn't solve the design problem:

simpleOne.pong.call(this);

Generally a class or a method needs to be injected with a function or object. This could be simple but this contradicts the principle of least privilege and gives instance to the whole this instance:

class SimpleTest {
    constructor(instance) {
      this.instance = instance;
    }
    pong() {
      this.instance.map();
    }
}
...
let simpleOne = new SimpleTest(this);
simpleOne.pong();

It's a better design to give it the access to the exact part of the instance it needs. Component methods are bound to the instance and can be passed as callbacks:

class SimpleTest {
    pong(map) {
      map();
    }
}
...
let simpleOne = new SimpleTest();
simpleOne.pong(this.map);

This isn't a good use case for classes because SimpleTest is stateless, and map doesn't make use of component instance. This could be achieved with plain functions:

function map() {...}

function pong() { ping() }

In case map uses component instance and pong needs to be declared outside a component, reusable functionality can be put to a mixin with options API:

let testMixin = {
  methods: {
    pong() {
      this.map();
    }
}
...
mixins: [testMixin],
methods: {
  map() {...},
},

This would be designed differently with composition API through composables.