Re: [PATCH] diffcore: add a filter to find a specific blob

[Jonathan Nieder <jrnieder@gmail.com>]

Stefan Beller wrote:
> On Thu, Dec 14, 2017 at 6:18 PM, Junio C Hamano <gitster@pobox.com> wrote:

>> I think it would make it a better companion to --pickaxe but we need
>> to align its behaviour a little bit so that it plays better with the
>> "--pickaxe-all" option, and also needs to hide mode and name only
>> changes just like pickaxe.
>
> I looked into this, and the small changes needed led me to thinking
> it could be integrated into the diffcore-pickaxe code completely,
> roughly like (spaces mangled):

Nice, this looks promising.

[...]
> But then, it seems as if any pickaxe option is incompatible with
> any other, i.e. from reading the code, you cannot combine -S
> and -G, or even give one of them twice.
>
> I guess that would be not a big deal for the --pickaxe-object,
> but just want to point it out.

Agreed that that's not a big deal for --pickaxe-object.

>> After all, the diffcore-blobfind code was written while looking at
>> the diffcore-pickaxe's code in another window shown in the pager,
>> and I tend to agree with your earlier message that this is an
>> extreme case of -S<contents> where the contents happens to be the
>> whole file.
>
> I disagree, as the user doesn't have the content, but the hash
> over the content only and wants to know more about it. The new
> option cannot be used to find a file whose partial content hashes to
> the given sha1, either.
>
> So with these considerations, I would keep the patch as currently\
> queued at sb/diff-blobfind.

Interesting --- I come to the opposite conclusion.

The pickaxe-style behavior seems more consistent and simpler to
explain and better matches the use cases I can think of.

Thanks,
Jonathan