From: Jeff King <peff@peff.net>
Date: Wed, 12 Jan 2011 17:46:00 GMT
Subject: Re: bug? in checkout with ambiguous refnames
Message-ID: <20110112174600.GB31747@sigill.intra.peff.net>
In-Reply-To: <20110112091130.GC24920@pengutronix.de>

On Wed, Jan 12, 2011 at 10:11:30AM +0100, Uwe Kleine-König wrote:

> > > So working copy and cache are at refs/tags/sgu/mxs-amba-uart, HEAD
> > > points to refs/heads/sgu/mxs-amba-uart
> > 
> > Yeah, we generally resolve ambiguities in favor of the tag (and that
> > warning comes from deep within get_sha1_basic). So the real bug here is
> > that it still said "Switched to branch", which is totally wrong.
> I wonder how I can resolve the ambiguity when calling checkout.  (Well
> apart from changing either branch name or tag name)
> 
> git checkout refs/heads/sgu/mxs-amba-uart results in a detached HEAD.

You can't disambiguate to the branch without going to a detached HEAD in
the current code; it's just broken[1].

With the patch here:

  http://article.gmane.org/gmane.comp.version-control.git/164986

it will disambiguate to the branch by default, and if you want the tag,
you can do:

  git checkout tags/sgu/mxs-amba-uart

-Peff

[1]: You can't do it with checkout, that is. You can still hack around
     it with:

        branch=refs/heads/sgu/mxs-amba-uart
        git read-tree -m -u $branch &&
        git symbolic-ref HEAD $branch

     which is a simplified version of what checkout is doing.