Refactor is_named_instance and refers_to_fullname

[sobolevn]

I saw that refers_to_fullname cannot use our new mypy.types.FINAL_DECORATOR_NAMES constant to work. So, I've decided to allow that.

In the process:

• I've also simplified is_named_instance function to allow Tuple as well (I use Tuple, because it is used for constants)
• I've also reused is_named_instance in refers_to_fullname
• Refactored several tuple-specific names into a new constant

[JelleZijlstra]

Not related to your diff, but I wonder why Sized and Collection aren't in here.

[sobolevn]

Do we need to open a new issue? 🤔

[JelleZijlstra]

Yes probably. I guess what this affects is whether a heterogeneous tuple type matches Sized or Collection?

[sobolevn]

Done #11961

[sobolevn]

Looks like I've accedentaly noticed a bug.

Here's the test definition of decorated_coroutine:

mypy/test-data/unit/check-async-await.test

Lines 606 to 608 in f6ebf10

	@coroutine
	async def decorated_coroutine() -> int:
	return 1

Later it is used as x = yield from decorated_coroutine()

Old error message: # E: "yield from" can't be applied to "AwaitableGenerator[Any, Any, int, Coroutine[Any, Any, int]]"

New error message: # E: "yield from" can't be applied to "Coroutine[Any, Any, int]"

>>> import types
>>> import asyncio
>>> @types.coroutine
... async def decorated_coroutine() -> int:
...     return 1
... 
>>> x = decorated_coroutine()
>>> type(x)
<class 'coroutine'>
>>> asyncio.run(x)
1

>>> async def main():
...   y = decorated_coroutine()
...   async for a in y:
...     print(a)
... 
>>> asyncio.run(main())
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/sobolev/Desktop/cpython/Lib/asyncio/runners.py", line 44, in run
    return loop.run_until_complete(main)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/sobolev/Desktop/cpython/Lib/asyncio/base_events.py", line 637, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "<stdin>", line 3, in main
TypeError: 'async for' requires an object with __aiter__ method, got coroutine

Double-checking:

>>> import inspect
>>> inspect.isasyncgenfunction(decorated_coroutine)
False
>>> inspect.isasyncgen(decorated_coroutine())
RuntimeWarning: Enable tracemalloc to get the object allocation traceback
False

@JelleZijlstra do you agree?

[JelleZijlstra]

Sorry, I'm not sure I understand. Note that AwaitableGenerator is a mypy-only type, used for pre-async def asyncio coroutines.

[sobolevn]

Note that AwaitableGenerator is a mypy-only type

Ok, I see. Then, it is not a bug. Thanks!