Spec using mock to call response method

viewmodel_spec.coffee

describe "ChildrenCheckinViewModel", ->

  beforeEach ->
    spyOn(jQuery, 'getJSON')
    @actualChildren = ko.observableArray()
    @subject = new Childcarepro.ChildrenCheckinViewModel @actualChildren
    @response = [
        {FIRSTNAME:'John',LASTNAME:'Locke',BIRTHDATE:12312312312},
        {FIRSTNAME:'Matt',LASTNAME:'Zandstra',BIRTHDATE:12312312312}
    ]
    @expectedChildren = [
      new Childcarepro.Child(@response[0])
      new Childcarepro.Child(@response[1])
    ]

  describe "Ajax loading of children", ->

    beforeEach -> @request = jQuery.getJSON.mostRecentCall

    it "calls the children api", -> expect(@request.args[0]).toBe '/children.json'
    
    it "loads all the children", ->
      @request.args[2] {children: @response}, 200
      expect(@subject.children().length).toBe 2