Re: [PATCH 5/5] diff: properly error out when combining multiple pickaxe options

From: Stefan Beller <sbeller@google.com>
Date: Jan 3, 2018, 22:18 UTC
Message-ID: <CAGZ79kaef93BVM+Xaihad7cij-tc6DvWAgwo+Ps1zt_3Jn84Tg@mail.gmail.com>
In-Reply-To: <xmqq7esyh9ym.fsf@gitster.mtv.corp.google.com>

On Wed, Jan 3, 2018 at 2:08 PM, Junio C Hamano <gitster@pobox.com> wrote:

Show 16 quoted lines

> Stefan Beller <sbeller@google.com> writes:
>
> ;
>> +     count = 0;
>> +
>> +     if (options->pickaxe_opts & DIFF_PICKAXE_KIND_S)
>> +             count++;
>> +     if (options->pickaxe_opts & DIFF_PICKAXE_KIND_G)
>> +             count++;
>> +     if (options->pickaxe_opts & DIFF_PICKAXE_KIND_OBJFIND)
>> +             count++;
>> +     if (count > 1)
>> +             die(_("-G, -S, --find-object are mutually exclusive"));
>
> I thought the reason you defined pickaxe-kind bitmask was so that
> you can mask this field to grab these (and only these) bits.

Originally I only wanted to mask out the 'case independency' bit and keep it future proof for any similar bits.

> Once you have that mask, you should be able to use HAS_MULTI_BITS()
> on the masked result without counting, no?

Oh, what a nice macro! Thanks for pointing at it.

As soon as I figured out the right place where to put this check, I saw the lines above, whose style I imitated. (I guess there is just no mask defined for "--name-only, --name-status, --check and -s", nor would it make sense to do so; though that given macro should work just fine even for non-continuous masks)