[Gnu-arch-users] Keeping original file contents in an update

[Yaron Minsky]

A recurrent problem I've had with arch is that by default, after a
conflict, update leaves a .rej file, which tells you what patches
didn't apply, and an .orig file, which tells you what the file looked
like before the attempt to apply your changes.  But what it doesn't
keep is a version of your files before the update.

To see why this is a problem, consider the case where you have a file
foo to which you've made extensive changes.  You do an update, to
discover that someone has made incompatible changes to the same file. 
You're left with a huge .rej file, and no clean way of getting back
your original file.  (the only way to do that, I think, is to apply
the ,,undo patch.  But you can't do it on a file-by-file basis, and
you can't do it at all once you've made other modifications to deal
with the other rej's.)  So, is there a good solution to this problem? 
  To me, this seems pretty serious, since it can involve loosing data.

(another solution would be to use replay.  But I prefer the semantics
of update and would rather avoid using replay)

Yaron