From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: move detection doesnt take filename into account
Date: Tue, 01 Jul 2014 07:57:36 -0700
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Cc: Elliot Wolk <elliot.wolk@gmail.com>, git@vger.kernel.org
To: Robin Rosenberg <robin.rosenberg@dewire.com>
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In-Reply-To: <287177519.16421.1404206204124.JavaMail.zimbra@dewire.com> (Robin
	Rosenberg's message of "Tue, 1 Jul 2014 11:16:44 +0200 (CEST)")
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Robin Rosenberg <robin.rosenberg@dewire.com> writes:

> I think it does, but based on filename suffix. E.g. here is a rename of
> three empty files with a suffix.
>
>  3 files changed, 0 insertions(+), 0 deletions(-)
>  rename 1.a => 2.a (100%)
>  rename 1.b => 2.b (100%)
>  rename 1.c => 2.c (100%)

This is not more than a chance.

We tie-break rename source candidates that have the same content
similarity score to a rename destination using "name similarity",
whose implementation has been diffcore-rename.c::basename_same(),
which scores 1 if `basename $src` and `basename $dst` are the same
and 0 otherwise, i.e. from 1.a to a/1.a is judged to be a better
rename than from 1.a to a/2.a but otherwise there is nothing that
favors rename from 1.a to 2.a over 1.a to 2.b.