New Twiddle

controllers.application.js

import Ember from 'ember';
import DS from 'ember-data';
import MyNativeClassModel from '../models/my-native-class-model';
import MyEmberObjectModel from '../models/my-ember-object-model';

function isModel(TestModel) {
  return TestModel !== DS.Model && DS.Model.detect(TestModel);
}

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  isModelNativeExtends: isModel(MyNativeClassModel),
  isModelEmberObjectExtends: isModel(MyEmberObjectModel),
});

models.my-ember-object-model.js

import Model from 'ember-data/model';
import attr from 'ember-data/attr';
import { belongsTo, hasMany } from 'ember-data/relationships';

export default Model.extend({
});

models.my-native-class-model.js

import Model from 'ember-data/model';
import attr from 'ember-data/attr';
import { belongsTo, hasMany } from 'ember-data/relationships';

export default class MyNativeClassModel extends Model {
}

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>

<hr>
<pre>dataAdapter.detect(DS.Model.extend())</pre>
{{isModelEmberObjectExtends}}
<hr>
<pre>dataAdapter.detect(class Foo extends DS.Model {})</pre>
{{isModelNativeExtends}}

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": "3.0.0",
    "ember-template-compiler": "3.0.0",
    "ember-testing": "3.0.0"
  },
  "addons": {
    "ember-data": "2.18.2"
  }
}