The python black project.

Monty Taylor mordred at
Thu Apr 18 14:00:32 UTC 2019

On 4/18/19 1:45 PM, Sean McGinnis wrote:
>> I think we already use flake8 openstack-wide, what will Black bring us in
>> addition to that?
>> Dmitry
> Based on my quick test, it would bring us code churn of changing ' to " and
> flake8 errors due to unwrapping lines and making them longer than 80
> characters.
> I like the idea of code consistency. But having a tool automatically do it
> without being able to tweak the settings, and having defaults do things that
> introduce pep8 errors, seems like a non-starter.
> And as mentioned elsewhere, introducing something like this to a long
> established code base has a lot of problems. Maybe new projects just starting
> off may want to investigate further, but running on most projects could be a
> nightmare.

I agree.

I actually looked at black a little while ago for openstacksdk - because 
I do like me some strict style rules. The long-line-length sucked, 
although making a tox env that passes a reasonable line-length worked 
around that.

The biggest problem is that, even in a pretty clean codebase that 
already tries to follow a lot of what black likes (line breaks after 
brackets - yes please!) - the churn was MASSIVE and really just not 
worth it.

If we were starting OpenStack from-scratch today, I'd recommend we adopt 
it. But we're not.

Also - if new projects decided to adopt black, we'd wind up with two 
conflicting codestyles across OpenStack, which is one of the things our 
long-standing gating on pep8 is supposed to prevent. I don't think it's 
a good idea for OpenStack to _partially_ adopt black.


More information about the openstack-discuss mailing list