Mypy: Release mypy 0.510

[JukkaL]

I'm planning the next mypy release (0.510) to happen around Thu/Fri of the week of May 1. [I.e. May 4-5.]

If you have any open PRs that you'd like to see included, leave a comment here and we'll see if it's possible. New features probably have to be merged on Tuesday at the latest. Documentation updates and high-priority, low-risk bug fixes can also land on Wednesday. Merging any PRs from Thursday until the time of the release is subject to approval from me.

Note that Monday is a UK bank holiday so don't expect a lot of activity from me.

[JelleZijlstra]

I'd like to see #3081 merged if possible.

[gvanrossum]

I vote to include per-file strict-optional: https://github.com/python/mypy/pull/3206 -- @ddfisher we should get agreement on the way forward (see my code review remarks).

[sixolet]

@JukkaL I have a sneaking suspicion your employer's interests would be served well by including https://github.com/python/mypy/pull/3291 which I just posted.

[gvanrossum]

Sadly we're so close to the release, and none of these PRs is quite ready to be merged, so they will all be postponed until after the release.

We have other things to do for the release (e.g. a typeshed sync) but we won't have time to rush in major features. Sorry!

[JelleZijlstra]

No problem! I'm excited for the new release.

[gvanrossum]

FWIW the plan is to release on Friday. There is now a code freeze where all mypy commits have to be approved by Jukka before merging. If we can't make it Friday we'll shoot for Monday.

[JukkaL]

The release went out! Blog post: http://mypy-lang.blogspot.co.uk/2017/05/mypy-0510-released.html

Thanks to all contributors!

We may have a bugfix release on Monday (-c is a little broken).