var item1 = Ember.Object.create({

  incl: true

});

​

var anObject = Ember.Object.extend({

  collection: [],

  filteredCollection1: Ember.computed.filterBy('collection', 'incl'),

  filteredCollection2: Ember.computed.filter('collection', function(item) {

    return item.get('incl');

  }),

  filteredCollection3: (function() {

    return this.get('collection').filterBy('incl');

  }).property('collection.@each.incl')

});

​

var object = anObject.create();

​

// Works without these gets

object.get('filteredCollection1');     

object.get('filteredCollection2'); 

object.get('filteredCollection3');

​

Ember.run.next(this, function() {

  // This works: 

  // object.get('collection').pushObjects([item1]);

  object.set('collection', [item1]);

​

  console.log(

    object.get('filteredCollection1.length') === 1,

    object.get('filteredCollection2.length') === 1,

    object.get('filteredCollection3.length') === 1 

  );

});

​