From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: [PATCH] Introduce <branch>@{tracked} as shortcut to the
 tracked branch
Date: Thu, 10 Sep 2009 10:16:18 -0400
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Cc: Junio C Hamano <gitster@pobox.com>,
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	Michael J Gruber <git@drmicha.warpmail.net>,
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To: Johannes Schindelin <Johannes.Schindelin@gmx.de>
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On Thu, Sep 10, 2009 at 11:36:42AM +0200, Johannes Schindelin wrote:

> diff --git a/Documentation/git-rev-parse.txt b/Documentation/git-rev-parse.txt
> index 82045a2..09a2145 100644
> --- a/Documentation/git-rev-parse.txt
> +++ b/Documentation/git-rev-parse.txt
> @@ -231,6 +231,10 @@ when you run 'git-merge'.
>  * The special construct '@\{-<n>\}' means the <n>th branch checked out
>    before the current one.
>  
> +* The suffix '@{tracked}' to a ref (short form 'blabla@{t}') refers to
> +  the branch tracked by that ref.  If no ref was specified, it means the
> +  branch tracked by the current branch.
> +

It looks like the code dereferences symbolic refs when doing the lookup
(so HEAD@{t} will find the upstream of the current branch), which I
think is the best thing to do. However, that does make it behave
slightly differently than HEAD@{2.minutes.ago}, so it may be worth
adding a sentence to this paragraph like:

  If the ref is a symbolic ref, it is dereferenced before searching
  for the upstream ref.

And we may want to add a test for HEAD, as well.

Also, I seem to be able to stimulate a segfault on a detached HEAD, but
I haven't investigated it yet.

-Peff