[Twisted-Python] mypy integrated with CI for twisted

[Glyph]

> On Jun 24, 2020, at 12:45 PM, Kyle Altendorf <sda at fstab.net> wrote:
> 
>> On 2020-06-24 00:43, Glyph wrote:
>> > On Jun 23, 2020, at 5:34 AM, Adi Roiban <adi at roiban.ro> wrote:
>> >
>> > Hi Craig,
>> >
>> > On Tue, 23 Jun 2020 at 00:36, Craig Rodrigues <rodrigc at crodrigues.org> wrote:
>> > I have merged some more fixes for mypy to Twisted trunk branch.
>> >
>> > In trunk, you can run mypy with:
>> >
>> > tox -e mypy
>> >
>> > Currently this results in 171 errors, which is way down from >1000 errors
>> > a month ago.
>> >
>> > In addition, if you look at any new PR's there is a Mypy Ubuntu job
>> > running on Azure pipeline, which runs mypy.  Right now errors from this job
>> > are ignored and does not block the PR.  However, if we can get the mypy
>> > errors down to zero, we can make mypy status a blocker for the PR.
>> >
>> > Thanks for working on this.
>> >
>> > Looking forward to have a real green mypy build.
>> >
>> > A general question: Why Twisted used Azure Devops and not GitHub actions?
>> Azure Pipelines gave us substantially more parallel capacity than is available via Github Actions, which means we can make build statuses appear much sooner.  Plus they support more platforms.
> 
> Just noticed we don't actually link to Azure from the readme.  Presently we have 14 builds there so within the tense pickiness :] we don't get any benefit (yet).

If 3 PRs are building at the same time, we see a benefit.

> I'm curious though, what additional platforms does Azure get us?

Oh, never mind! Last I was investigating this Actions was Linux-only; looks like they've really improved a lot!

-g