Null Reference Error When Trying To Unit Test Code Setting

        public async Task<Messaging.BaseTypes.BaseWidget> GetWidgetAsync(string widgetId)

        {

            var widget = await RetrieveWidget(widgetId, true); //true here fires off other if-else logic for what to do 

                      //with a null widget

            if (widget != null) return widget.Application;

            Response.StatusCode = 404; //this is the line that throws the null reference error. Says Response is not set to 

                //an instance of an object.

            return null;

        }

 

I can test the happy path and get it to return the widget, but when I try to test the Response.StatusCode line, the code throws a null reference error every time. What am I missing? Here is my test code. 

 

 

My understanding is when I do this:

    var controllerUnderTest = Isolate.Fake.Dependencies<WidgetApplication>();

 

it should create all dependencies of the <Widget>