From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Subject: Re: [PATCH v2] Introduce <branch>@{upstream} as shortcut to the
 tracked branch
Date: Thu, 10 Sep 2009 18:18:46 +0200 (CEST)
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References: <20090907084324.GB17997@coredump.intra.peff.net> <alpine.DEB.1.00.0909071126040.8306@pacific.mpi-cbg.de> <20090909104550.GA20108@coredump.intra.peff.net> <7vzl93cncn.fsf@alter.siamese.dyndns.org> <alpine.DEB.1.00.0909100941330.8306@pacific.mpi-cbg.de>
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Cc: Junio C Hamano <gitster@pobox.com>,
	=?ISO-8859-15?Q?Bj=F6rn_Steinbrink?= <B.Steinbrink@gmx.de>,
	Michael J Gruber <git@drmicha.warpmail.net>,
	Pete Wyckoff <pw@padd.com>, git@vger.kernel.org
To: Jeff King <peff@peff.net>
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Hi,

On Thu, 10 Sep 2009, Jeff King wrote:

> I wrote:
> 
> > +	ret = tracked_suffix(*string, *len);
> > +	if (ret) {
> > +		char *ref = xstrndup(*string, *len - ret);
> > +		struct branch *tracking = branch_get(*ref ? ref : NULL);
> > +
> > +		free(ref);
> > +		if (!tracking)
> > +			die ("No tracking branch found for '%s'", ref);
> > +		if (tracking->merge && tracking->merge[0]->dst) {
> > +			*string = xstrdup(tracking->merge[0]->dst);
> > +			*len = strlen(*string);
> > +			return (char *)*string;
> > +		}
> > +	}
> > +
> 
> I don't think it is a good idea to die for !tracking, but not for
> !tracking->merge. That leads to inconsistent user-visible results:
> 
>   $ git checkout HEAD^0
>   $ git rev-parse HEAD@{u}
>   fatal: No tracking branch found for 'HEAD'
>   $ git rev-parse bogus@{u}
>   bogus@{u}
>   fatal: ambiguous argument 'bogus@{u}': unknown revision or path not in the working tree.
>   Use '--' to separate paths from revisions
> 
> Shouldn't both cases say the same thing?
> 
> Also, your die message has two problems:
> 
>  1. It looks at ref immediately after it is free'd, spewing junk.
> 
>  2. Ref can be the empty string, which gives you the ugly:
> 
>        fatal: No tracking branch found for ''
> 
>     Should we munge that into HEAD (or "the current branch") for the
>     user?

All true, but I cannot take care of it today.

Ciao,
Dscho