anchor.diff:  
   [source,groovy]
   ----
  -def subscriber = GroovyMock(Subscriber)
  +Subscriber subscriber = GroovyMock()
   
   1 * subscriber.someDynamicMethod("hello")
   ----
  
positive.code: 
  [source,groovy]
  ----
  def anySubscriber = GroovySpy(RealSubscriber, global: true)
  
  1 * new RealSubscriber("Fred")
  ----
  
negative.code: 
  [source,groovy]
  ----
  Subscriber subscriber = Mock {
     1 * receive("hello")
     1 * receive("goodbye")
  }
  