During development of your driver, and certainly before releasing it, you should use the Driver Conformance Checker tool to test your driver. This tool performs a comprehensive set of tests on a driver to determine its conformance with the relevant ASCOM interface standard. It also tests some aspects of driver behavior against the reference implementation. Conform is a really useful tool to use during development as it exercises all driver functionality. This means you don't have to develop your own set of basic test harnesses to test your driver.
Here are the results from Conform-checking the Platform 6 .NET Focuser Simulator:
ConformanceCheck ASCOM Device Conformance Checker Version 126.96.36.199 ConformanceCheck Running on ASCOM Platform 6.0 ConformanceCheck Driver ProgID: ASCOM.Simulator.Focuser Error numbers Error number for "Not Implemented" is: 80040400 Error number for "Invalid Value 1" is: 80040404 Error number for "Value Not Set" is: 80040403 09:51:29.425 Driver Access Checks OK 09:51:30.042 AccessChecks OK Successfully created driver using late binding 09:51:30.062 AccessChecks OK Successfully connected using late binding 09:51:30.065 AccessChecks INFO The driver is a .NET object 09:51:30.068 AccessChecks INFO The AssemblyQualifiedName is: ASCOM.Simulator.Focuser, ASCOM.Simulator.Focuser, Version=188.8.131.52, Culture=n 09:51:30.072 AccessChecks INFO The driver implements interface: ASCOM.DeviceInterface.IFocuserV2 09:51:30.075 AccessChecks INFO The driver implements interface: System.IDisposable 09:51:30.697 AccessChecks INFO Device does not expose IFocuser interface 09:51:30.724 AccessChecks INFO Device exposes IFocuserV2 interface 09:51:30.745 AccessChecks OK Successfully created driver using driver access toolkit 09:51:30.756 AccessChecks OK Successfully connected using driver access toolkit Conform is using ASCOM.DriverAccess.Focuser to get a Focuser object 09:51:30.786 ConformanceCheck OK Driver instance created successfully 09:51:30.798 ConformanceCheck OK Connected OK Common Driver Methods 09:51:30.834 InterfaceVersion OK 2 09:51:30.840 Connected OK True 09:51:30.846 Description OK ASCOM Focuser Simulator Driver 09:51:30.851 DriverInfo OK Focuser Simulator Driver 09:51:30.856 DriverVersion OK 6.0 09:51:30.860 Name OK ASCOM.Simulator.Focuser 09:51:30.866 CommandString INFO Conform cannot test the CommandString method 09:51:30.870 CommandBlind INFO Conform cannot test the CommandBlind method 09:51:30.874 CommandBool INFO Conform cannot test the CommandBool method 09:51:30.878 Action INFO Conform cannot test the Action method 09:51:30.882 SupportedActions OK Driver returned an empty action list Properties 09:51:30.906 Absolute OK True 09:51:30.911 IsMoving OK False 09:51:30.915 MaxStep OK 50000 09:51:30.920 MaxIncrement OK 50000 09:51:30.924 Position OK 25000 09:51:30.929 StepSize OK 20 09:51:30.934 TempCompAvailable OK True 09:51:30.938 TempComp Read OK False 09:51:30.942 TempComp Write OK Successfully turned temperature compensation on 09:51:30.947 TempComp Write OK Successfully turned temperature compensation off 09:51:30.952 Temperature OK 4.69 Methods 09:51:30.970 Halt OK Focuser halted OK 09:51:30.979 Move Moving to position: 30000 09:51:38.003 Move OK Asynchronous move found 09:51:38.010 Move OK Absolute move OK 09:51:45.036 Move Moving to position: 30000 09:51:45.063 Move - TempComp True OK .NET InvalidOperation Exception correctly raised as expected Conformance test complete No errors, warnings or issues found: your driver passes ASCOM validation!! Driver Hash Value: A353EA89A605A6A3F27FF72C7981A8AC0A745CF8868080E6F3359451B56E29A9EC58F860BA2261884E5D0BA3ADCFB691D5B05C1E28FD951D3D968FF3AD276A68 Report Hash Value: 7DE8DA5D641C48876F3451D4D3F98ECFAA296D7DD07D77122F4C6B67117AB6AE1AAE4DA66305CE2D853276F5B4F068128E558D2598A4F3D78C64FE2206C15C0B