Re: Unresolved issues #3

["Catalin Marinas" <catalin.marinas@gmail.com>]

On 18/08/06, Junio C Hamano <junkio@cox.net> wrote:
> Catalin Marinas <catalin.marinas@arm.com> writes:
> > In StGIT I can configure the merge command and I currently use the
> > attached script (I need to add it to the StGIT repository). It tries
> > diff3 first and, if that fails, invokes emacs' merge (can use xxdiff
> > as well). It also checks whether the file was modified in case I want
> > to exit and solve the conflict later (maybe after getting conflict
> > information for the other files).
>
> Thanks.  That is interesting.  However, the workflow Martin
> wants to use this is a bit different from this.  He wants
> regular diff3/merge to leave conflicted result and have "xxdiff
> -U" to sort out the resulting mess (I do that manually myself
> but without any wrapper).

The problem with this approach is that you lose the ancestor
information. You want "diff3 -E" command to not report conflicts if
the changes are the same but the output no longer has the ancestor
information. The -A option would keep the ancestor (and use "xxdiff
--unmerge3" instead) but it always reports a conflict even if the
changes are the same. Are there any diff3 options I missed?

That's why I prefer to explicitely pass the 3 files to either emacs or xxdiff.

> > # default merger
> > if os.system('diff3 -L current -L ancestor -L patched -m -E '
> >              '"%s" "%s" "%s" > "%s"'
> >              % (branch1, ancestor, branch2, output)):
> >     # interactive merge
> >     if os.path.exists(output):
> >         mtime = os.path.getmtime(output)
> >     else:
> >         mtime = 0
>
> I wonder why you do not error out when "if os.path.exists(output)"
> does not hold true; you are redirecting into it, so the possibilities
> are:

You are right. I was thinking about the file removed in the current
branch but modified in the other. However, this would never invoke
diff3.

Thanks.

-- 
Catalin