On Wed, Aug 09, 2017 at 07:19:00PM -0400, Jeff King wrote:
> On Wed, Aug 09, 2017 at 03:53:17PM -0700, Stefan Beller wrote:
> 
> > >> Right, the reason I stopped pursuing it was that I couldn't find a way
> > >> to have it make suggestions for new code without nagging about existing
> > >> code. If we were to aggressively reformat to match the tool for existing
> > >> code, that would help. But I'm a bit worried that there would always be
> > >> suggestions from the tool that we don't agree with (i.e., where the
> > >> guiding principle is "do what is readable").
> > 
> > We may have different opinions on what is readable/beautiful code.
> > If we were to follow a mutual agreed style that is produced by a tool,
> > we could use clean/smudge filters with different settings each.
> 
> I'm less worried about a difference of opinion between humans. My
> concern is that there are cases that the tool's formatting makes _worse_
> than what any human would write. And either we accept ugly code because
> the tool sucks, or we spend a bunch of time fighting with the tool to
> try to make its output look good.

This has been my issue with clang-format in the past.  I have an SHA-256
implementation with an array of 64 32-bit hex integers.  These fit six
to a line, but for neatness and consistency reasons, I'd like them four
to a line (4 divides 64, but 6 does not).  Last I checked, clang-format
didn't allow me that option: it reordered them because it could fit six
on a line.  This is not the only issue I discovered, just the most
memorable.

Other tools, such as perltidy, have traditionally honored existing line
breaks better (although not perfectly), which lets humans optimize for
readability.

Of course, clang-format could have dramatically improved since I last
looked (which was around clang 3.4 or 3.6, I think).

Overall, I do like the idea of using tidy tools, because it does reduce
quibbling over style quite a bit.  I just like the tools to be more
responsive to the whitespace they're given on input.
-- 
brian m. carlson / brian with sandals: Houston, Texas, US
https://www.crustytoothpaste.net/~bmc | My opinion only
OpenPGP: https://keybase.io/bk2204