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From:   Leonardo Bras <leobras@redhat.com>
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Leonardo Bras <leobras@redhat.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Randy Dunlap <rdunlap@infradead.org>,
        Nicolas Schier <nicolas@fjasle.eu>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org
Subject: Re: [RFC PATCH v5 1/1] scripts: Introduce a default git.orderFile
Date:   Tue, 12 Dec 2023 14:09:43 -0300
Message-ID: <ZXiT1zyADQVXOEqw@LeoBras>
In-Reply-To: <ZXhbUmxzH6nWAzaw@infradead.org>
References: <20231208181802.88528-3-leobras@redhat.com> <ZXgMa57Ere6FJCJB@infradead.org> <CAK7LNAQiJW0eFYQZN0wuURhrdc-8y7=TcEazpxhLf=+mRbKHHQ@mail.gmail.com> <ZXhbUmxzH6nWAzaw@infradead.org>
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On Tue, Dec 12, 2023 at 05:08:34AM -0800, Christoph Hellwig wrote:
> On Tue, Dec 12, 2023 at 05:09:21PM +0900, Masahiro Yamada wrote:
> > Unlike .gitignore, this feature is opt-in rather than enforced.
> > 
> > To use this, you need to run
> > 
> > 'git config diff.orderFile scripts/git.orderFile'
> > 
> > or
> > 
> > 'git diff -C scripts/git.orderFile'
> 
> Oh, ok.  That greatly reduces my concern.

Yes, it's an opt-in, so no user should be directly impacted.

> 
> > 
> > Indeed, the file order is subjective, leaving
> > us a question "do we need it in upstream"?

The main idea is patch generation.
This file's order is supposed to be the best order for reading a raw patch 
and understanding the code changes. 

> > 
> > At least, it is harmless for people who have no interest.
> 
> .. but this is still a good question.  I'm not really sure there is
> much of a need for it, but as long as it doesn't harm everyone else
> I'm at least neutral on it.

diff.orderfile was introduced in git to help order the git diff, and thus 
the patch generation, in a way that it's easier to understand what the 
commit / patch intends on doing. 

Take this example introducing a feature foo, you should see:
- Documentation on foo, if introduced
- How is foo enabled in build system, if needed
- The types / stucts / fields introduced by foo, if any
- The interface for using foo, if any
- The actual foo implementation.

Of course the actual order is open to discussion, and I encourage everyone 
to suggest any other items or order.

Thanks!
Leo