v1.15.0 breaking checks using Coroutine

[gabrielcocenza]

Bug Report

Since the new release, one of the projects that I use mypy is failing for the type Coroutine.

The code is like this:

from typing import Coroutine,

def compare_step_coroutines(
 coro1: Optional[Coroutine], coro2: Optional[Coroutine]
) -> bool:
 """Compare two coroutines.

 :param coro1: coroutine to compare
 :type coro1: Optional[coroutine]
 :param coro2: coroutine to compare
 :type coro2: Optional[coroutine]
 :return: True if coroutines are equal
 :rtype: bool
 """
 if coro1 is None or coro2 is None:
 # compare two None or one None and one Coroutine
 return coro1 == coro2

 return (
 # check if same coroutine was used
 coro1.cr_code == coro2.cr_code
 # check coroutine arguments
 and inspect.getcoroutinelocals(coro1) == inspect.getcoroutinelocals(coro2)
 )

lint: commands[2]> mypy --install-types --non-interactive .
cou/steps/__init__.py:48: error: "Coroutine[Any, Any, Any]" has no attribute "cr_code" [attr-defined]

With this new release Coroutine doesn't recognize cr_code as a valid property.
I've tried to change to use types.CoroutineType and fixed for this issue, but errors started showing on other parts of the code. mypy still consider as Coroutine. E.g:

class Foo
def __init__(self, coro: Optional[types.CoroutineType] = None):
 self._coro: Optional[[types.CoroutineType] = coro

foo = Foo(coro=my_coro_func)

async def my_coro_func():
 return None

Argument "coro" to "Foo" has incompatible type "Coroutine[Any, Any, None]"; expected "CoroutineType[Any, Any, Any] | None" [arg-type] note: Maybe you forgot to use "await"?

Basically Coroutine cannot be used anymore like before and I don't see a possible workaround without ignoring the line that is complaining or pinning mypy to use a version < 1.15.0

Your Environment

• Mypy version used: 1.15.0
• Mypy command-line flags: mypy --install-types --non-interactive .
• Mypy configuration options from mypy.ini (and other config files):

warn_unused_ignores = true
warn_unused_configs = true
warn_unreachable = true
disallow_untyped_defs = true
ignore_missing_imports = true
exclude = [
 ".eggs",
 ".git",
 ".tox",
 ".venv",
 ".build",
 "build",
 "lib",
 "report",
 "tests",
 "docs"
]

• Python version used:3.12

[A5rocks]

This is intentional. You can have coroutines without cr_code. This works:

from typing import Coroutine

def compare_step_coroutines(
 coro1: Coroutine, coro2: Coroutine
) -> bool:
 assert hasattr(coro1, "cr_code")
 assert hasattr(coro2, "cr_code")
 return coro1.cr_code == coro2.cr_code

Comment I left on typeshed for more information: python/typeshed#10816 (comment)

[A5rocks]

Note of course that the more correct thing to check is isinstance(coro, types.CoroutineType):

from typing import Coroutine
from types import CoroutineType

def test1(
 coro: Coroutine
) -> None:
 assert isinstance(coro, CoroutineType)
 reveal_type(coro.cr_code) # N: Revealed type is "types.CodeType"

def test2(
 coro: Coroutine
) -> None:
 assert hasattr(coro, "cr_code")
 reveal_type(coro.cr_code) # N: Revealed type is "Any"