How to pass an object to Ember.Handlebars.helper - ember.js

Question

I'm trying to find out how to pass an Ember object through Handlebars to a helper function. Any ideas of how to do this?
Data
groups = [
{
id:'as93-2dsa',
name:'read'
},
{
id:'dk20-d23k',
name: 'write'
},
{
id: 'mn20-8al3',
name: 'execute'
}
];
user = {
id:'lk30-a8bk',
name: 'Seth'
groupIDs:[
'as93-2dsa',
'lk30-a8bk'
]
}
HTML
{{inGroup groups user}}
Controller
Ember.Handlebars.helper('inGroup', function(groups, user) {
/**
* At this point I would expect groups to be and object and user to be an object
* but both return classes
*/
console.log(groups);
//Class {toString: function, __ember1418251045900: "ember646", __nextSuper: undefined, __ember_meta__: Object, constructor: function…}
console.log(groups.toString());
// "<DS.PromiseArray:ember646>"
console.log(user);
//Class {id: "5CF3A051-12B4-436C-B43A-5696F2792B55", store: Class, container: Container, _changesToSync: Object, _deferredTriggers: Array[0]…}
console.log(user.toString());
// "<nfors-app#model:user::ember526:5CF3A051-12B4-436C-B43A-5696F2792B55>"
/**
* I would like to access groups[i].id and user.groupIds in a way such as the following
*/
for (var i = 0; i < groups.length; i++) {
if (user.groupIds.indexof(groups[i].id) !== -1) {
return true;
}
}
return false;
});
User Model
import DS from 'ember-data';
import EmberValidations from 'ember-validations';
export default DS.Model.extend(EmberValidations.Mixin, {
name: DS.attr('string'),
groupIds: DS.hasMany('groupIds', { async: true }),
validations: {
name: {
presence: true,
length: { minimum: 5 }
}
}
});