Re: [PATCH 3/3] rebase -i: use "git sequencer--helper --reset-hard"

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

Sverre Rabbelier <srabbelier@gmail.com> writes:

> Heya,
>
> On Sun, Aug 2, 2009 at 23:29, Christian Couder<chriscool@tuxfamily.org> wrote:
>> This is part of my work to port git-rebase--interactive.sh to C using code
>> from the sequencer project. So the advantage is that it introduces and uses
>> the reset_almost_hard() function that will be used in the end when
>> everything is done by C code.
>
> Hmmm, that almost makes sense, but I don't see the new C code
> replacing any existing shell code, so what am I missing here?

More importantly, I found the "almost_hard()" function way underexplained.
What it does (e.g. does --hard when able but otherwise gives up and falls
back to something else?), why it is necessary (e.g. when should callers
use it, instead of calling unconditional "reset --hard"?), what kind of
preparation is necessary by the caller (e.g. should it read the index
before calling the function?  should it discard the index before?), and
what kind of result should it expect (e.g. is it safe to write a tree out
of the resulting index, or does it screw up the cache-tree and the caller
should discard it before writing a tree?), etc. etc....