Jasmine Tips - http://c0d3it.blogspot.com/2013/04/jasmine-tips-spies.html

checking_events.coffee

# model file
class SimpleModel extends Backbone.Model

# view file
class SimpleView extends Backbone.View
  # click listener
  onClick: ->
    @model.trigger("selected")
    
# spec file
describe "SimpleView", ->
  beforeEach -> SimpleModel()
    @simpleModel = new SimpleModel()
    @simpleView = new SimpleView(model: @simpleModel)
  describe "onClick", ->
    it "triggers @model selected", ->
      #spy
      @listener = ->
      spyOn(@, "listener")
      #bind
      @simpleModel.on("selected", @listener)
      #trigger
      @simpleView.onClick()
      #expect
      expect(@listener).toHaveBeenCalled()
      

checking_events_called_with.coffee

describe "onClick", ->
    it "triggers @model selected", ->
      #spy
      spyOn(@simpleModel, "trigger")
      #trigger
      @simpleView.onClick()
      #expect
      expect(@simpleModel.trigger).toHaveBeenCalledWith("selected")
      

late_spy.coffee

# model file
class SimpleModel extends Backbone.Model
  initialize: ->
    @on("selected", @onSelected)

  onSelected: =>


#spec file
describe "SimpleModel", ->
  beforeEach -> @simpleModel = new SimpleModel()
  it "calls onSelected when selected is triggered", ->
    spyOn(@simpleModel.onSelected)
    @simpleModel.trigger("selected")
    expect(@simpleModel.onSelected).toHaveBeenCalled() # this expectation will fail.

late_spy_fixed.coffee

# model file
class SimpleModel extends Backbone.Model
  initialize: -> @bindEvents()
  bindEvents: ->
    @on("selected", @onSelected)

  onSelected: =>


#spec file
describe "SimpleModel", ->
  beforeEach -> @simpleModel = new SimpleModel()
  it "calls onSelected when selected is triggered", ->
    spyOn(@simpleModel.onSelected)
    @simpleModel.bindEvents()
    @simpleModel.trigger("selected")
    expect(@simpleModel.onSelected).toHaveBeenCalled() # this expectation will pass.

spy.coffee

#spec file
describe "simple spy", ->
  it "replaces passed function", ->
    dummy = -> 7
    spyOn(dummy)
    expect(dummy()).not.toBe(7)

spy_and_call_fake.coffee

#view file
class SimpleView extends Backbone.View
  onFormSubmit: (e)=>
    e.preventDefault()    
    @model.save
      error: @onSaveError
      success: @onSaveSuccess
    
  onSaveError: =>
  onSaveSuccess: =>
    

#spec file
describe "SimpleView", ->
  beforeEach -> 
    @simpleModel = new SimpleModel()
    @simpleView  = new SimpleView(model: @simpleModel)
  describe "onFormSubmit"
    before -> @e = {preventDefault -> }
    
    it "calls onsave error when error", ->
      spyOn(@simpleView, "onSaveError")
      #trigger error callback
      spyOn(@simpleModel, "save").andCallFake (obj)-> obj.error()
      @simpleView.onFormSubmit(@e)
      expect(@simpleView.onSaveError).toHaveBeenCalled()
    
    it "calls onsave success when success", ->
      spyOn(@simpleView, "onSaveSuccess")
      #trigger success callback
      spyOn(@simpleModel, "save").andCallFake (obj)-> obj.success()
      @simpleView.onFormSubmit(@e)
      expect(@simpleView.onSaveSuccess).toHaveBeenCalled()
  

spy_and_call_through.coffee

#spec file
describe "spy and call through", ->
  it "can call through", ->
    dummy = -> 7
    spyOn(dummy).andCallThrough()
    expect(dummy()).toBe(7)

spy_and_return.coffee

describe "spy and return", ->
  it "can also be told to return a specific value", ->
    dummy = -> 7
    spyOn(dummy).andReturn(17)
    expect(dummy()).toBe(17)