Compare two fxcop results

Question

Hi,

I'm going to analysis two different versions of the same dll with fxcop. I would like to display only the differences between these two reports. Does anyone know if this is possible ?

Thanks for your time.

Answer 1

Yes, it's possible, but there are no built-in tools available for this. One fairly simple approach would be to use a diff tool to compare the two reports. If the result is too noisy for you, another approach would be to roll your own tool to compare the XML of the two reports.

Answer 2

Are you using UI or the command line?

With the command line tool, you have a number of options. One of them is to import an old report to be used as a baseline. Then set the fxcop project to report only new errors: Report Status="Active, Absent" NewOnly="True"

The command line will be something like this: fxcopcmd.exe /i:OldVersionReport.xml /out:NewVersionReport.xml /p:FXCopProject.fxcop /f:mydll.dll

The new report will have only new active error and also a list of missing i.e. fixed errors from the old version.

While this will work for the most part, you need to understand that the difference will not be 100% acurate. FXCop does its best to match old report to the new version of the DLL, but sometimes it fails. For example, if you fixed a particular violation somewhere in code, but added the same type of violation in another place, FXCop will most likely miss this and show no difference.