From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: [PATCH v2 3/4] Speed up is_git_command() by checking early for
 internal commands
Date: Fri, 3 Jan 2014 10:44:26 -0500
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Cc: Sebastian Schuberth <sschuberth@gmail.com>,
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To: Junio C Hamano <gitster@pobox.com>
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On Thu, Jan 02, 2014 at 11:41:05AM -0800, Junio C Hamano wrote:

>  - builtin/merge.c is the same, but it is conceptually even worse.
>    It has the end-user supplied string and wants to see if it is a
>    valid strategy.  If the user wants to use a custom strategy, a
>    single stat() to make sure if it exists should suffice, and the
>    error codepath should load the command list to present the names
>    of available ones in the error message.

Is it a single stat()? I think we would need to check each element of
$PATH. Though in practice, the exec-dir would be the first thing we
check, and where we would find the majority of hits. So it would still
be a win, as we would avoid touching anything but the exec-dir in the
common case.

-Peff