Re: [RFC PATCH 4/4] name-rev: avoid naming from a ref if it’s not a descendant of any commit

From: Alban Gruin <alban.gruin@gmail.com>
To: Christian Couder <christian.couder@gmail.com>
Cc: Git Mailing List <git@vger.kernel.org>
Subject: Re: [RFC PATCH 4/4] name-rev: avoid naming from a ref if it’s not a descendant of any commit
Date: Sun, 3 Mar 2019 21:27:59 +0100	[thread overview]
Message-ID: <10fa15ee-a6f4-805b-bae3-14ea8c50c048@gmail.com> (raw)
In-Reply-To: <CAP8UFD1HBbOX7wS664vBT8mxjGUJ4rtWYYJJX9RQqhN20-T8uA@mail.gmail.com>

Hi Christian,

Le 03/03/2019 à 20:33, Christian Couder a écrit :
> On Fri, Mar 1, 2019 at 7:11 PM Alban Gruin <alban.gruin@gmail.com> wrote:
>>
>> A ref may not be the descendant of all of the commits mentionned in
>> stdin.  In this case, we want to avoid naming its parents.
> 
> Properly speaking a ref usually just points to a commit. It is not a
> parent or a descendant of any commit.
> 
> Also if the commit, let's call it C, pointed to by a ref isn't a
> descendant of a commit, let's call it C', mentioned on stdin, then C'
> isn't a parent of C, though I think we want to avoid naming C' from
> the ref.
> 
> I think it might be clearer with something like:
> 
> "The commit, let's call it C, pointed to by a ref may not be a
> descendant of all the commits mentioned on stdin. In this case we want
> to avoid naming the commits mentioned on stdin that are not parents of
> C using the ref."
> 
> Or is there something I misunderstood?
> 

It’s almost this.  We do want to name *all* of the commits mentionned in
stdin, as far as possible.  We also want to lower the amount of memory
allocation, and one of the possibilities is to avoid traversing the tree
from a commit pointed to by a ref if none of its parents are mentionned
in stdin.

Cheers,
Alban