删除操作的单元测试

Question

这是删除操作，我想进行单元测试和

def deleteRoutineTable()
    {   def deleteRoutineTableId=params.id;
       def routineTable=RoutineTable.get(deleteRoutineTableId);
        routineTable.delete()
        redirect(action: "routineTable")
    }

这是测试代码......但这显示错误..as

def newRoutintable=new RoutineTable(id:1,name: "routine",institution:1,endTime: new Date(),startTime: new Date())
                newRoutintable.save(flush:true)
                newRoutintable.list().size()+1
                when:
               controller.deleteRoutineTable()
                then:newRoutintable.list().size()-1

        }

失败：|

testDelete(routine.RoutineTableControllerSpec)
 |
java.lang.NullPointerException: Cannot invoke method delete() on null object
    at routine.RoutineTableController.deleteRoutineTable(RoutineTableController.groovy:54)
    at routine.RoutineTableControllerSpec.testDelete(RoutineTableControllerSpec.groovy:60)