public void UpdateImagesTestNullData() { var simSystem = new StubPLCSim() { ReadOutputImageInt32Int32ImageDataTypeConstantsObjectRef = (int a, int b, ImageDataTypeConstants c, ref object pData) => { pData = null; } }; var target = new SimulatedPLC(simSystem); simSystem.Connect(); target.OutputImageOffestRequest(5); try { target.UpdateImages(); } catch (Exception e) { Assert.Fail("Exception thrown by UpdateImages call\n" + e.ToString()); } finally { simSystem.Disconnect(); } //Assert.Fail("Exception not found"); }