Re: [PATCH v2 6/7] reflog-walk: stop using fake parents

From: Jeff King <peff@peff.net>
Date: Jul 9, 2017, 10:08 UTC
Message-ID: <20170709100837.kr5fs2kva6bdrole@sigill.intra.peff.net>
In-Reply-To: <87van48cpu.fsf@kyleam.com>

On Fri, Jul 07, 2017 at 11:54:05AM -0400, Kyle Meyer wrote:

Show 18 quoted lines

> Jeff King <peff@peff.net> writes:
> 
> >      Prior to this commit, we show both entries with
> >      identical reflog messages. After this commit, we show
> >      only the "comes back" entry. See the update in t3200
> >      which demonstrates this.
> >
> >      Arguably either is fine, as the whole double-entry
> >      thing is a bit hacky in the first place. And until a
> >      recent fix, we truncated the traversal in such a case
> >      anyway, which was _definitely_ wrong.
> 
> Yeah, I agree that the double-entry thing is a bit hacky and only
> showing the "comes back" entry makes sense.
> 
> And with this change, I believe that the display of a rename event will
> be the same for HEAD's log and the renamed branch's log, despite the
> underlying entries having a different representation.

There's one minor difference: the numbering for HEAD will show a "hole" in the reflog. So on the branch you might see something like:

  $ git log -g --oneline other
  269000b other@{0}: Branch: renamed refs/heads/master to refs/heads/other
  269000b other@{1}: commit (initial): foo

but the HEAD reflog will show:

  $ git log -g --oneline HEAD
  269000b HEAD@{0}: Branch: renamed refs/heads/master to refs/heads/other
  269000b HEAD@{2}: commit (initial): foo

This is pretty minor. I do wonder if there are other bits that might be confused, though. Looking at the hole is odd:

  $ git show --oneline HEAD@{1}
  warning: Log for ref HEAD unexpectedly ended on Sun, 9 Jul 2017 06:07:05 -0400.
  269000b foo

Despite the warning, we do seem to correctly walk past it, though:

  $ git show --oneline HEAD@{2}
  269000b foo

-Peff