Set vs. Push Objects Behaviour

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  prop: Ember.computed('_data.prop.[]', {
    get() {
      return this._data['prop'];
    }
  }),
  
  sortedProp: Ember.computed('prop.@each.time', {
    get() {
      return this.prop.sort((a, b) => a.time - b.time);
    }
  }),
  
  init() {
    this.set('_data', { prop: [] });
  },
  
  actions: {
    updatePropViaSet() {
      Ember.set(this._data, 'prop', [...this._data.prop, ...[{ time: 100 }]]);
    },
    
    updatePropViaPushObjects() {
      this._data.prop.pushObject({ time: 100 });
    }
  }
});

templates.application.hbs

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

<button {{action 'updatePropViaSet'}}>Update via Set</button>

<button {{action 'updatePropViaPushObjects'}}>Update via Push Objects</button>

{{#each sortedProp as |prop|}}
	{{prop.time}}
{{/each}}
<br>
{{outlet}}
<br>
<br>

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}