this Object ref in Util function

components.new-foo-comp.js

import funcSpecial from '../utils/my-special-func';

import Ember from 'ember';

export default Ember.Component.extend({
  foo: 123,
  newFoo: funcSpecial(this, 'foo')
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
});

routes.index.js

import Ember from 'ember';

export default Ember.Route.extend({
});

templates.application.hbs

{{outlet}}

templates.components.new-foo-comp.hbs

New Foo: {{newFoo}}

templates.index.hbs

{{new-foo-comp}}

twiddle.json

{
  "version": "0.15.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.2.2",
    "ember-template-compiler": "3.2.2",
    "ember-testing": "3.2.2"
  },
  "addons": {
    "ember-data": "3.2.0"
  }
}

utils.my-special-func.js

import Ember from 'ember';

export default function funcSpecial(thisObj, keyToAdd) {
 	// Ember.defineProperty(thisObj, 'secretVal', 999);
  
  console.log(thisObj);
  
  const secretVal = 999;
  
  let resVal = secretVal + thisObj.get(keyToAdd);
  return resVal;
}