[Fwd: [Gnu-arch-users] star-merge and commit on one file only]

[mbp at ozlabs.org]

> I just saw this show up on the Arch mailing list, and I realized it is
> something that we should probably think about for bzr.
> If I do a merge, and then try to do a partial commit, it seems like the
> merge shouldn't count.

I agree.

In general systems that assign whole-tree revision ids, as bzr and most
others do, are going to have some amount of trouble with partial merges or
partial commits of merges.  We can simply say they're rare and not
completely accurately tracked, and that might be enough.

If we store per-file-revision parents, as weaves will likely do, then we
might be able to do better.  But there is the potential for a lot of
confusion when, say, two files receive different changesets in different
orders.  We could say that each file really does have its own version
history, and the whole-tree just references them.  That probably
complicates both the internal model and the user presentation quite a lot;
a presentation of the history of the whole tree may be missing some
changes merged into particular files.  It might ease joining of trees, or
subdirectories shared between different branches.

-- 
martin