(🐞) Call to function decorated with a Callable causes inner function to fail to infer type of variable

[KotlinIsland]

from typing import Any, Callable, TypeVar, _T as T

def bar() -> None:
    def inner() -> None:
        it.encode()  # error: Cannot determine type of 'it'
    breaks()
    it = ""
    
deco: Callable[[T], T]

@deco
def breaks() -> None: ...

It appears that the order of the function declarations affects the result(:trollface:):

from typing import Any, Callable, TypeVar

T = TypeVar("T")

deco: Callable[[T], T]

@deco
def doesnt_break() -> None: ...

def bar() -> None:
    def inner() -> None:
        it.encode()  # no error
    doesnt_break()
    it = ""

I have determined that this only happens when the deco is a Callable, when it is a function there is no error:

from typing import Any, TypeVar, _T as T

def bar() -> None:
    def inner() -> None:
        it.encode()  # no error
    doesnt_break()
    it = ""
    
def deco(fn: T) -> T: ...

@deco
def doesnt_break() -> None: ...

playground

[KotlinIsland]

topic-inference When to infer types or require explicit annotations ?

[JelleZijlstra]

I meant "inference" to mean ways to infer types for unannotated code. This feels different though I don't know how to classify it. It's probably a bug somewhere in semanal?