Re: [PATCH 01/23] contrib/coccinnelle: add equals-null.cocci

From: Junio C Hamano <gitster@pobox.com>
Date: Apr 30, 2022, 20:56 UTC
Message-ID: <xmqqpmky70jb.fsf@gitster.g>
In-Reply-To: <6e8cd958-b749-0a55-d8ae-ff249f06bd2f@iee.email>

Philip Oakley <philipoakley@iee.email> writes:

Show 14 quoted lines

> On 30/04/2022 05:13, Elia Pinto wrote:
>> Add a coccinelle semantic patch necessary to reinforce the git coding style
>> guideline:
>>
>> "Do not explicitly compute an integral value with constant 0 or '\ 0', or a
>
> s/compute/compare/
>> pointer value with constant NULL."
>
> If this gets re-rolled, perhaps include a simple example for those who
> don't immediately understand that quoted sentence. It will also help
> decode the coccinelle script
>
> so:     `if (ptr == NULL)` becomes `if (!ptr)`  etc.

That is certainly a good suggestion, but I am wondering if we want to also emphasize another more generally applicable rule that appears much earlier in the guideline document:

 - Fixing style violations while working on a real change as a
   preparatory clean-up step is good, but otherwise avoid useless code
   churn for the sake of conforming to the style.

   "Once it _is_ in the tree, it's not really worth the patch noise to
   go and fix it up."
   Cf. http://lkml.iu.edu/hypermail/linux/kernel/1001.3/01069.html