Angularjs unit testing - factory

file.factories.coffee

angular
  .module('app.moduleA', ['app.moduleB'])
  .factory('FactoryA', (FactoryB) ->
    factory = {}
    
    factory.sayHello = () -> FactoryB()
    
    return factory
  )

angular
  .module('app.moduleB', [])
  .factory('FactoryB', () ->
    return () -> "hello"
  )

file.factories.test.coffee

describe "app.moduleA", ->
  factory = undefined
  
  beforeEach(module('app.moduleA'))
  beforeEach(module(($provide) ->
    $provide.value('FactoryB', () -> "world")
    return null
  ))
  beforeEach(() ->
    inject((FactoryA) ->
      factory = FactoryA
    )
  )

  it "exists", () ->
    expect(factory.sayHello()).toEqual("world")