From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joel Reed <joelwreed@gmail.com>
Subject: Re: git-diff on touched files: bug or feature?
Date: Thu, 2 Aug 2007 09:25:41 -0400
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Cc: Matthieu Moy <Matthieu.Moy@imag.fr>,
	Junio C Hamano <gitster@pobox.com>, git@vger.kernel.org
To: Johannes Schindelin <Johannes.Schindelin@gmx.de>
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On Thu, Aug 02, 2007 at 01:19:55PM +0100, Johannes Schindelin wrote:

<snip>

> For performance reasons, git always compares the files' stat information 
> with that stored in the index.
> 
> By updating the file, you make that check fail always.
> 
> Without updating the index (which is not a read-only operation, and 
> therefore must not be done when doing a read-only operation like diff), 
> you will therefore _destroy_ the main reason of git's kick-ass 
> performance.

The idea that read-only operation like diff shouldn't update the
index makes a lot of sense.

But, as a user of git and not a git developer, I certainly _thought_
that git-status was a read-only operation as well. Now I know it
isn't, but this doesn't seem very consistent.

jr