From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] diff: Support diff.color-words config option
Date: Tue, 20 Jan 2009 12:27:06 -0800
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To: Johannes Schindelin <Johannes.Schindelin@gmx.de>
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 (Johannes Schindelin's message of "Tue, 20 Jan 2009 18:28:14 +0100 (CET)")
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Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

>> By the way, wouldn't it make sense to optimize the precontext of that 
>> hunk by doing _something_ like:
>> 
>> 	if (!o->word_regex && strcmp(one->path, two->path))
>>         	o->word_regex = userdiff_word_regex(two);
>> 
>> "Something like" comes from special cases like /dev/null for new/deleted
>> files, etc.
>
> You mean to avoid the cost of initializing the regex in case one and the 
> same file is diffed against itself?

No.

What I meant is much simpler than that.

If one and two are the same filename, and earlier gitattributes lookup for
the path already failed to produce any when you checked one, isn't it very
likely that the gitattributes lookup for two would fail the same way to
produce any result?