Re: Merge symmetry (was: Tree Conflicts with Subversion 1.7)

On Fri, Aug 19, 2011 at 04:15:38PM +0200, Andreas Krey wrote:
> On Fri, 19 Aug 2011 13:51:40 +0000, Stein Somers wrote:
>
> > Now I realize merges are always asymmetric.
>
> Actually, merging is a symmetric operation. The tree (and copyfrom
> info) resulting from a merge should be the same independent of in
> which direction the merge is performed.

I agree that symmetry is a nice-to-have property of a merge algorithm.

But I would be totally happy with asymmetric results, as long as either
result is well-defined and repeatable. I don't see why the behaviour
of a merge algorithm must be symmetric.

> In svn the metadata just looks
> completely different depending on the direction of the merge. (It also
> is different due to the necessity of --reintegrate.)

Sounds like you are conflating the UI with the underlying design.
--reintegrate is a UI issue and has nothing to do with symmetry
or correctness.
See http://mail-archives.apache.org/mod_mbox/subversion-dev/201107.mbox/%3C20110720124721.GA7557@ted.stsp.name%3E
Received on 2011-08-22 12:39:33 CEST