Identified atcheckstyle/eclipse-cs#380 (comment) ,

It was not clear why we were getting random issues and then it became clear patch-filters prevented a Checkstyle run in some cases, which is its purpose.

It would be helpful if patch-filters reported something minor like "No files identified as changed" or "Identified X files as changed" so it is clear when allows Checkstyle to run and not run.

I don't think it would have helped this case, but it will make what it is doing clearer.