From: Jacob Keller <jacob.keller@gmail.com>
Date: Thu, 07 Dec 2017 18:57:23 GMT
Subject: Re: git commit file completion recently broke
Message-ID: <CA+P7+xrhgbcogxYa38jEu3PuF5hVNNYPjAq031bYE8bgao168Q@mail.gmail.com>
In-Reply-To: <xmqq8teeftn7.fsf@gitster.mtv.corp.google.com>

On Thu, Dec 7, 2017 at 7:24 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Christian Couder <christian.couder@gmail.com> writes:
>
>>> I do think it may make sense for
>>> the "short" one to use NULL, like:
>>>
>>>   skip_to_optional_val(arg, "--relative, &arg)
>>>
>>> but maybe some other callers would be more inconvenienced (they may have
>>> to current NULL back into the empty string if they want to string
>>> "--foo" the same as "--foo=").
>>
>> I discussed that with Junio and yeah there are many callers that want
>> "--foo" to be the same as "--foo=".
>
> Yup, the original thread has details and me saying that assuming all
> of them want --foo and --foo= the same is questionable.  The likely
> fix would be to use the _default variant with NULL, which was added
> exactly for cases like this.
>

Slightly more complex. You have to use the _default variant, pass in
arg instead of options->prefix, and then make sure arg was set before
overwriting options->prefix. If you just use _default with NULL, it
will not quite fix the problem.

Thanks,
Jake