[Development] clang-format

[André Pönitz]

On Wed, Jun 20, 2018 at 06:30:26AM +0000, Lars Knoll wrote:
> 
> 
> > On 19 Jun 2018, at 18:19, Ville Voutilainen
> > <ville.voutilainen at gmail.com> wrote:
> > 
> > On 19 June 2018 at 19:13, Philippe <philwave at gmail.com> wrote:
> >>> For the above reasons I'd lean towards not running it globally and
> >>> just using it on new changes.
> >> 
> >> +1, based on my clang-format experience on a big application.
> >> 
> >> BTW, keep in mind that you can disable clang-format on code
> >> sections with:
> >> 
> >> // clang-format off // clang-format on
> > 
> > When I last experienced a large-scale clang-format reformat, it
> > really hurt development during the churn. We should somehow manage
> > to do it during a time when there aren't many pending patches in the
> > pipeline. I'm not concerned about git-blame; that has never been a
> > problem after reformats. However, I do not care about indentation
> > nor do I want to spend time on it either way, it has no actual
> > effect on readability and maintainability of code, and consistency
> > outside the file you're in has never mattered to me one bit.
> > 
> > IOW, I'm not opposed to reformats and auto-checking of clang-format
> > (or even hooking it), but I do not see it as a thing with all that
> > great return-of-investment.
> 
> It helps in that you do not need to point those things out in code
> reviews, and that I (and others) won’t even create changes with wrong
> formatting that I’ll need to fix up later on. It’s part of a larger
> story, where I would like to get as much automatic checking of changes
> done before humans start reviewing.

It's also a cultural thing.

Quite a few people seem to take less offense from a "Your formatting is
bad" when the comment comes from a bot than when it comes from a human. 

> One idea could be to introduce this incrementally. Let’s first start
> off with enforcing it for new changes. Then we run it globally over
> the code base shortly before Qt 6.0 is being released. At that time
> merges shouldn’t be as much of a problem (as we’ll probably
> cherry-pick into Qt 5.15) and by then all new changes in Gerrit will
> be properly formatted (due to the earlier hook).

Incrementally sounds good to me.

Still I am a bit of a fence here. So far I've seen a couple of auto-
formatting attempts biting back, so I thinl it would help to convince me
to see the kind of changes that would happen first before deciding
on the global change.

Andre'