http://stackoverflow.com/questions/39176566/loading-promise-in-handlebars-templates-based-on-volatile-computed-property/39177310#39177310

components.people-you-may-know.js

import Ember from 'ember';

export default Ember.Component.extend({
  invite:Ember.inject.service(),
  actions:{
    logout(){
      //console.log('addOneEntry');
      //this.get('invite').addOneEntry();
      this.get('invite').logout();
    },
    login(){
      this.get('invite').login();
    }
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  
  reversedItems: Ember.computed('model.[]', function() {
    return this.get('model').toArray().reverse();
  }),
  reducedItems: Ember.computed('model.[]', function() {
    return this.get('model').toArray().slice(0,2);
  })
});

mirage.config.js

export default function() {
  
  this.get('history-items');

};

mirage.factories.user.js

import { Factory, faker } from 'ember-cli-mirage';

export default Factory.extend({
  name() {
    return faker.name.findName();
  }

});

mirage.fixtures.history-items.js

export default [
  { id: 1 },
  { id: 2 },
  { id: 3 },
  { id: 4 }
];

mirage.models.history-item.js

import { Model } from 'ember-cli-mirage';

export default Model.extend({
});

mirage.scenarios.default.js

export default function(server) {
  // added this line because global wasn't created otherwise.
  
  window.server = server;
  server.loadFixtures();
  
}

mirage.serializers.application.js

import { JSONAPISerializer } from 'ember-cli-mirage';

export default JSONAPISerializer.extend({
});

models.history-item.js

import DS from 'ember-data';

export default DS.Model.extend({
});

routes.application.js

import Ember from 'ember';

export default Ember.Route.extend({
  
  model() {
    return this.store.findAll('history-item');
  }
  
  
});

services.invite.js

import Ember from 'ember';

export default Ember.Service.extend({
  store:Ember.inject.service(),
  
  recommendations: Ember.computed({
    get(key) {
      console.log('recommendations get - key',key);
      return this.get('store').findAll('history-item');
    },
    set(key,value) {
      console.log('recommendations set key',key,'value',value);
      return this.get('store').findAll('history-item');
    }
	}),
  
  reducedRecommendations: Ember.computed('recommendations.[]',function(){
    console.log('reducedRecommendations',this.get("recommendations"));
  	return this.get("recommendations").slice(0,2);
	}),
    
  logout(){
    //console.log('unloading');
    this.get('store').unloadAll('history-item');
  },
  login(){
    console.log('login');
    this.set('recommendations','dummyvalue');
    
  }
});

templates.application.hbs

<h1>Mirage boilerplate</h1>

{{#each reversedItems as |item|}}
  <p>{{item.id}}</p>
{{/each}}

{{#each reducedItems as |item|}}
  <p>{{item.id}}</p>
{{/each}}

{{people-you-may-know }}

templates.components.people-you-may-know.hbs

<h2>people-you-may-know</h2>
{{#each invite.recommendations as |person|}}
 {{person.id}}
 {{/each}}
 <h2> reduced </h2>
 {{#each invite.reducedRecommendations as |person|}}
 {{person.id}}
 {{/each}}
 <button {{action "logout"}}> Logout </button>
 <button {{action "login"}}> Login </button>
{{yield}}

tests.acceptance.my-acceptance-test.js

import { test } from 'qunit';
import moduleForAcceptance from '../../tests/helpers/module-for-acceptance';

moduleForAcceptance('TODO: put something here');

test('visiting /my-acceptance', function(assert) {
  server.create('user', { name: 'Link' });
  console.log('the users are', server.db.users);
  
  visit('/');

  andThen(function() {
    assert.ok(find(':contains(Welcome Link!)').length);
  });
});

tests.helpers.destroy-app.js

import Ember from 'ember';

export default function destroyApp(application) {
  Ember.run(application, 'destroy');
}

tests.helpers.module-for-acceptance.js

import { module } from 'qunit';
import startApp from '../helpers/start-app';
import destroyApp from '../helpers/destroy-app';

export default function(name, options = {}) {
  module(name, {
    beforeEach() {
      this.application = startApp();

      if (options.beforeEach) {
        options.beforeEach.apply(this, arguments);
      }
    },

    afterEach() {
      if (options.afterEach) {
        options.afterEach.apply(this, arguments);
      }

      destroyApp(this.application);
    }
  });
}

tests.helpers.resolver.js

import Resolver from '../../resolver';
import config from '../../config/environment';

const resolver = Resolver.create();

resolver.namespace = {
  modulePrefix: config.modulePrefix,
  podModulePrefix: config.podModulePrefix
};

export default resolver;

tests.helpers.start-app.js

import Ember from 'ember';
import Application from '../../app';
import config from '../../config/environment';

export default function startApp(attrs) {
  let application;

  let attributes = Ember.merge({rootElement: "#test-root"}, config.APP);
  attributes = Ember.merge(attributes, attrs); // use defaults, but you can override;

  Ember.run(() => {
    application = Application.create(attributes);
    application.setupForTesting();
    application.injectTestHelpers();
  });

  return application;
}

tests.test-helper.js

import resolver from './helpers/resolver';
import {
  setResolver
} from 'ember-qunit';

setResolver(resolver);

twiddle.json

{
  "version": "0.9.3",
  "ENV": {
    "ember-cli-mirage": {
      "enabled": true
    }
  },
  "EmberENV": {
    "FEATURES": {
      "ds-finder-include": true
    }
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.4.4/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.4.3/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.4.4/ember-template-compiler.js"
  },
  "addons": {
    "ember-cli-mirage": "0.2.1"
  }
}