From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 14 Aug 2020 01:06:22 GMT
Subject: Re: [PATCH v3 1/2] revision: differentiate if --no-abbrev asked explicitly
Message-ID: <xmqqzh6yyr1t.fsf@gitster.c.googlers.com>
In-Reply-To: <20200814005947.GA9518@danh.dev>

Đoàn Trần Công Danh  <congdanhqx@gmail.com> writes:

> Let me list some combination here:
>
> * none of --abbrev --no-abbrev --full-index -> default short index
> * --abbrev --full-index                     -> full-index
> * --full-index --abbrev                     -> full-index
> * --abbrev --no-abbrev                      -> full-index
> * --no-abbrev --abbrev=[n]                  -> shortened index to n char
>
> So, we can't use full_index bit, because --no-abbrev can be defeated
> by --abbrev, but --full-index will always win --abbrev.

Sure, I wasn't suggesting to flip the flags.full_index bit upon
seeing "--no-abbrev".  When --no-abbrev is in effect (i.e. the last
one among --no-abbrev, --abbrev, or --abbrev=n), .abbrev field is
set to 0.  So wouldn't it be sufficient to say

 - If flags.full_index bit is set, show the full object name

 - If abbrev is 0, show the full object name

 - All other cases, after clamping the value of abbrev to reasonable
   value, truncat the object name to that length

What am I missing?

> I'm planning for:
>
> * BOTH --abbrev and --no-abbrev but NOT --full-index;
> * BOTH --abbrev AND --full-index