svn feature request: print URL in diff output

[Paolo Bonzini]

I would like that svn print the URL of each file in the diff output, 
like CVS's `RCS file'.  One of the scripts I use to test GCC (which I 
have not contributed yet because of the svn transition) used it to 
detect the directory in which the patch should apply.

Danny, can you do it for 1.3?  If not (as I think), I can work on it myself.
Paolo