Is there a quick way to find changes between 2 versions of a map?

I recently found out someone made unofficial edit of my map dr_4halls. The latest official version is V6, but someone made a V6a. I've managed to get a hold of a copy of this v6a version and I would like to find out what changes they have made.

I have tried using the 'Diff map file' function which places "similar" items in a visgroup named as such, but according to the VDC the function is broken and incomplete. When I tried it, it seemed to put most things in that visgroup. So either whoever edited the map made a lot of changes, or that function of Hammer is broken.

So what I'd like to know is there any other way you can compare changes between 2 versions of the same map in order to work out what has been changed?

 

Diffing requires good versions of the source files. Decompiled versions hardly count as good versions. Even the tiniest decompilation artifact will cause a false positive in a diff. And if there is a very common, but tiny, difference, then the diff becomes nearly useless.

 

You would only be able to easily track changes if the the unofficial edit was made using the original vmf, if the vmf is reconstructed for example when decompiled the vmf would be differently structured than the one you have this would make it impossible to track the changes.

 

Well it turns out the only edit that happened was a file rename. Someone for whatever reason, changed the file name from 'dr_4halls_v6.bsp' to 'dr_4halls_v6a.bsp'

Decompiling the 'edited' map and checking the assets showed all the core map files had not been changed:


A CDC check confirmed that the 2 versions of the map were in fact the same.