Ember - Attempting to register an unknown factory

I have my route structure like this:

abc (route)
    |-- index
    |       |-- route.js (extends base.js)
    |       |-- template.hbs
    |
    |-- edit
    |       |-- route.js (extends base.js)
    |       |-- template.hbs
    |
    |-- base.js (extends Ember.Route)

Now when I am trying to write the unit test for my base.js I am getting the following exception:

Promise rejected before it exists: Attempting to register an unknown factory: route:abc/base

What's wrong I have done that it isn't able to register my base class as route.?

If I change my base.js to route.js then it starts working, but what happen is that the afterModel inside base.js get executed twice when I make transition to abc/index(this is expected behavior). My base class contains code that is required by both of the index and edit route.

Is there any better way to deal with this.?