Emitter.prototype.on = function (event, listener)
{
    if (typeof this.events[event] !== 'object')
    {
        this.events[event] = [];
     }

     this.events[event].push(listener);
 };

describe('#on', () =>
{
    it('should subscribe to an event name and be called when
    triggered', () =>
{

    Emitter.on(EVENT_NAME_ONE, spyFunction);
    //Emitter.trigger(EVENT_NAME_ONE);

    expect(spyFunction.calls.count()).toBe(1);
 });