On 25.06.2013, at 18:45, Stefan Sperling wrote: > On Tue, Jun 25, 2013 at 05:59:27PM +0200, Tobias Bading wrote: >> Hmm, but why is diff -cM:N working if the file was copied from >> revision M? Sure, the target of the copy operation did not exist in >> revision N-1 if M < N-1, but it didn't exist in revision M either. > > The file did exist at the copyfrom location in revision M, correct? > In which case Subversion can detect that the files at their respective > paths in revision M and N are related, so it displays a diff between > them. The revision N-1 doesn't matter in this case. It is not "operative" > on the file, and is ignored. > > But if you restrict the operative revision range of your diff such that > the copy source is not within that range, why would you expect Subversion to > still look for changes in that revision, and show a diff against the copy > source? I believe that 'svn diff' is giving you the right answer based on > parameters you've given it to work with. > > I realise that I'm not helping you much. I'm just explaining the > current intended behaviour. I don't think you've found a bug.
I wouldn't call it a bug either, but even less a feature ;-). I'm simply expecting -cN to mean "the changes made in revision N", not the changes between revisions N-1 and N. In most cases there's no difference in both interpretations, but with copies that warp time (so to speak) by copying from source@M to target@N with M < N-1, 'diff -cN target' is as useful as 'cat </dev/null' :-(. > The emacs vc-svn.el (sorry I didn't know that "plugin" is not the proper > term to use here) would indeed need to pass something more clever than > a hardcoded -rN-1:N to yield a useful result in your use case. *slowly waves his hand in front of Stefan* "This is not the editor you're looking for... move along." :-D Seriously though, what would you have to do if you have the path of a FILE in the working copy and a revision number N and you would like to know what was changed in that file in that revision? Something like 'svn log --limit 2 -rN:0 FILE' and if that returns two revision, take the second one (let's call it M) and do a 'svn diff -rM:N FILE'? Where's my Beißholz when I need it?!? :-D > The location of a file across revision history is not a very simple issue > in Subversion, and can sometimes be counterintuitive. If you haven't > done so I recommend reading this page for more information about how > Subversion resolves paths in history: > http://svnbook.red-bean.com/en/1.7/svn.advanced.pegrevs.html Thanks for the tip. I read it a few years ago, maybe I should read it again :-). Tobias
