From: "SZEDER Gábor" <szeder@ira.uka.de>
To: Junio C Hamano <gitster@pobox.com>
Cc: git@vger.kernel.org
Subject: Re: [PATCH 11/19] bash prompt: use bash builtins to find out current branch
Date: Wed, 9 May 2012 23:11:43 +0200 [thread overview]
Message-ID: <20120509211143.GE6958@goldbirke> (raw)
In-Reply-To: <7vzk9hqg0u.fsf@alter.siamese.dyndns.org>
On Wed, May 09, 2012 at 01:02:41PM -0700, Junio C Hamano wrote:
> SZEDER Gábor <szeder@ira.uka.de> writes:
>
> > Since HEAD is a single-line file and the symbolic ref format is quite
> > simple to recognize and parse,...
>
> Strictly speaking, that is true only if you somehow know that HEAD is not
> a symlinked symref. You may end up reading [0-9a-f]{40} out of HEAD
> without learning where the symbolic link pointed at.
>
> I personally do not _know_ of anybody who is still using a symlinked
> symref, but the reasoning behind 9f0bb90 (core.prefersymlinkrefs: use
> symlinks for .git/HEAD, 2006-05-02) cannot go away by definition until
> every project that benefited from the configuration the commit introduced
> goes extinct, so I wouldn't be surprised if you get complaints from the
> users if we adopt this patch.
Symlinked symref, wow. That was long before my time ;)
So, let's see whether I understand it correctly:
- If HEAD is a symlink, then it's a symlinked symref, and points to
a real ref file somewhere under refs/.
- If HEAD is a regular file, then it's either a symref containing
'ref: refs/...', or it's a detached HEAD containing 40 hexdigits.
If the above is right, then we could check with bash builtins whether
HEAD is a symbolic link, which is cheap, and stick to '$(git
symbolic-ref HEAD)' if it is, or use bash builtins if it isn't, right?
This way we could get most of the performance benefits for modern
HEADs, while still supporting symlinked symrefs.
Gábor
next prev parent reply other threads:[~2012-05-09 21:11 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-09 0:44 [PATCH 00/19] Bash prompt speedup SZEDER Gábor
2012-05-09 0:44 ` [PATCH 01/19] tests: move code to run tests under bash into a helper library SZEDER Gábor
2012-05-09 0:44 ` [PATCH 02/19] tests: add tests for the bash prompt functions in the completion script SZEDER Gábor
2012-05-09 8:07 ` Johannes Sixt
2012-05-09 18:08 ` Junio C Hamano
2012-05-10 6:09 ` Johannes Sixt
2012-05-09 18:36 ` Junio C Hamano
2012-05-09 20:33 ` SZEDER Gábor
2012-05-09 0:44 ` [PATCH 03/19] completion: use __gitdir() in _git_log() SZEDER Gábor
2012-05-09 18:41 ` Junio C Hamano
2012-05-09 19:01 ` SZEDER Gábor
2012-05-09 0:44 ` [PATCH 04/19] completion: respect $GIT_DIR SZEDER Gábor
2012-05-09 8:09 ` Johannes Sixt
2012-05-09 18:54 ` Junio C Hamano
2012-05-09 0:44 ` [PATCH 05/19] bash prompt: don't show the prompt when .git/HEAD is unreadable SZEDER Gábor
2012-05-09 19:32 ` Junio C Hamano
2012-05-09 19:45 ` SZEDER Gábor
2012-05-09 0:44 ` [PATCH 06/19] bash prompt: return early from __git_ps1() when not in a git repository SZEDER Gábor
2012-05-09 0:44 ` [PATCH 07/19] completion: make __gitdir() store repository path in $__git_dir SZEDER Gábor
2012-05-09 19:36 ` Junio C Hamano
2012-05-09 0:44 ` [PATCH 08/19] completion: use $__git_dir instead of $(__gitdir) SZEDER Gábor
2012-05-09 19:43 ` Junio C Hamano
2012-05-09 20:22 ` SZEDER Gábor
2012-05-09 20:56 ` Junio C Hamano
2012-05-09 21:36 ` SZEDER Gábor
2012-05-09 0:44 ` [RFC PATCH 09/19] completion: platform-specific helper function to get physical path SZEDER Gábor
2012-05-09 7:37 ` Johannes Sixt
2012-05-09 0:44 ` [PATCH 10/19] completion: use bash builtins to search for repository SZEDER Gábor
2012-05-09 19:52 ` Junio C Hamano
2012-05-09 22:34 ` SZEDER Gábor
2012-05-09 22:59 ` Junio C Hamano
2012-05-09 0:44 ` [PATCH 11/19] bash prompt: use bash builtins to find out current branch SZEDER Gábor
2012-05-09 20:02 ` Junio C Hamano
2012-05-09 21:11 ` SZEDER Gábor [this message]
2012-05-09 21:25 ` Junio C Hamano
2012-05-09 21:45 ` SZEDER Gábor
2012-05-09 21:50 ` Junio C Hamano
2012-05-09 0:44 ` [PATCH 12/19] bash prompt: use bash builtins to check whether inside git dir SZEDER Gábor
2012-05-09 8:07 ` Johannes Sixt
2012-05-09 20:06 ` Junio C Hamano
2012-05-09 0:44 ` [PATCH 13/19] bash prompt: check whether inside the worktree only when necessary SZEDER Gábor
2012-05-09 0:44 ` [PATCH 14/19] bash prompt: use bash builtins to find out current branch during rebase SZEDER Gábor
2012-05-09 0:44 ` [PATCH 15/19] bash prompt: use bash builtins to get detached HEAD abbrev. object name SZEDER Gábor
2012-05-09 0:44 ` [PATCH 16/19] bash prompt: display stash and upstream state even inside the repository SZEDER Gábor
2012-05-09 0:44 ` [PATCH 17/19] bash prompt: use bash builtins to check stash state SZEDER Gábor
2012-05-09 0:44 ` [RFC PATCH 18/19] bash prompt: avoid command substitution when checking for untracked files SZEDER Gábor
2012-05-09 20:32 ` Junio C Hamano
2012-05-09 0:44 ` [PATCH 19/19] bash prompt: alternative git prompt without command substitution SZEDER Gábor
2012-05-09 19:38 ` Andrew Sayers
2012-05-09 22:08 ` SZEDER Gábor
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