Re: [WIP PATCH] Manual rename correction

[Junio C Hamano <gitster@pobox.com>]

Jeff King <peff@peff.net> writes:

> On Tue, Jul 31, 2012 at 11:01:27PM -0700, Junio C Hamano wrote:
> ...
>> As we still have the pathname in this codepath, I am wondering if we
>> would benefit from custom "content hash" that knows the nature of
>> payload than the built-in similarity estimator, driven by the
>> attribute mechanism (if the latter is the case, that is).
>
> Hmm. Interesting. But I don't think that attributes are a good fit here.
> They are pathname based, so how do I apply anything related to
> similarity of a particular version by pathname? IOW, how does it apply
> in one tree but not another?

When you move porn/0001.jpg in the preimage to naughty/00001.jpg in
the postimage, they both can hit "*.jpg contentid=jpeg" line in the
top-level .gitattribute file, and the contentid driver for jpeg type
may strip exif and hash the remainder bits in the image to come up
with a token you can use in a similar way as object ID is used in
the exact rename detection phase.

Just thinking aloud.