Python 3.11 tracking issue

[hauntsaninja]

General, language:

• Fix typed_ast support for Python 3.11 (fixed in 1.5.4)
• Get tests running (Run Python 3.11 tests in CI #12833)
• Unbreak mypyc (Python 3.11 support mypyc/mypyc#931)
• Fixes for asyncio.coroutine removal (Use async def in pythoneval tests #12834, Remove failing test on Python 3.11 #12917)
• Fix mypyc traceback tests
• Make tests on Python 3.11 required
• Run lxml tests on Python 3.11
• PEP 654 (exception groups)
• Support for new enum features (New enum features in Python 3.11 #12841)
• Add tests for the following language changes: Syntax error with async generator inside dictionary comprehension cpython#77527 , Unpacking without parentheses is allowed since 3.9 cpython#90881
• Building wheels
• Adding classifier

New typing features:

• PEP 655 (Required, NotRequired)
• PEP 646 (variadic generics, Support for PEP 646 #12280)
• PEP 673 (Self type, support pep 673 Self type #11871)
• PEP 675 (LiteralString, Support PEP 675 (LiteralString) #12554, Recognise LiteralString as str #12559)
• PEP 681 (dataclass_transform, Support PEP 681 (dataclass_transform) #14293)

[AlexWaygood]

I started off writing a comment, but it got too long so I created a separate issue instead: there's a ton of new enum features in 3.11 that mypy doesn't yet support.

• New enum features in Python 3.11 #12841

[hauntsaninja]

Okay, we're down to four failing tests with Python 3.11:

FAILED mypyc/test/test_run.py::TestRun::run-misc.test::testCheckVersion
FAILED mypyc/test/test_run.py::TestRun::run-classes.test::testProtocol
FAILED mypyc/test/test_run.py::TestRun::run-classes.test::testPickling
FAILED mypyc/test/test_run.py::TestRun::run-classes.test::testProperty

#13125 takes care of testCheckVersion
testProperty seems trivial, just a difference in traceback formatting
testPickling is probably python/cpython#70766 and not too bad
testProtocol looks a little scary — seems like one we'd want to fix

[hauntsaninja]

@97littleleaf11 any interest in taking a look at the testProtocol failure? :-)

[hauntsaninja]

#13206 should fix testProtocol and testPickling
beta5 has some new test failures (that are my fault from python/cpython#94948 ), these ones are very easy to fix

[hauntsaninja]

Okay, CPython has rolled back changes, see python/cpython#92678 and python/cpython#95589. We should still confirm that with RC or B6 or whatever, we'll just have testProperty failing.

[NeilGirdhar]

If you want to link the PEP 673 issue, it's here: #11871

[hauntsaninja]

Okay, with RC1 we have the following tests failing:

testPickling: probably related to https://github.com/python/cpython/issues/70766 (although not sure why #13206 "fixed" this)
testProperty: as mentioned above, just a difference in traceback formatting
testConfigFollowImportsSysPath: looks like something might have changed in mypy type logic and we now detect an overload situation in typeshed 3.11-only code

[yoni-lavi]

Hypothetically speaking, if I wanted to add support for dataclass_transform, would that be a possibility?
does it need some kind of approval to even begin? Is it being worked on already?

[ethanhs]

It is not being worked on as far as I am aware, and you don't need approval, feel free to get started on working on it if you are interested! We use a mypy plugin to analyze dataclasses so you'll probably want to start there https://github.com/python/mypy/blob/master/mypy/plugins/dataclasses.py

[Viicos]

Since Python 3.11, Any is considered to be a base class. As stated here, mypy doesn't seem to support this feature yet when using NewType:

T = NewType("T", Any)
> error: Argument 2 to NewType(...) must be subclassable (got "Any")  [valid-newtype]

The issue was closed as wontfix but maybe this can now be supported?

[NeilGirdhar]

Added #14293 for PEP 681 so that we can track it 😄

[randolf-scholz]

What about the changes to Concatenate introduced by python/cpython#30969? (#14656)

[wesleywright]

I believe we can consider dataclass_transform supported now

[jorenham]

For completeness' sake, here's the PEP 646 issue:
#12280

[ilevkivskyi]

I don't think we need to keep this open. Almost everything is now implemented, and for couple remaining things we have dedicated issues.