Incorrect annotation for forward reference in generated constructor

[jjudas-resistant]

When a class is decorated with @define or @frozen, and an attribute references a type declared later in the file, the generated __init__ method contains a type annotation that is different from the one on a hand-written __init__ method.

In Python 3.14 without from __future__ import annotations:

import inspect

from attrs import define


class Works:
    def __init__(self, foo: Foo) -> None:
        self._foo = foo


@define
class DoesNotWork:
    _foo: Foo


class Foo:
    pass


# prints `(foo: __main__.Foo) -> None`
print(inspect.signature(Works))

# prints `(foo: Foo) -> None` (a ForwardRef)
print(inspect.signature(DoesNotWork))

With from __future__ import annotations (tested on both 3.14 and 3.13 - same result):

from __future__ import annotations

import inspect

from attrs import define


class Works:
    def __init__(self, foo: Foo) -> None:
        self._foo = foo


@define
class DoesNotWork:
    _foo: Foo


class Foo:
    pass


# prints `(foo: __main__.Foo) -> None`
print(inspect.signature(Works, eval_str=True))

# crashes with `NameError: name 'Foo' is not defined`
print(inspect.signature(DoesNotWork, eval_str=True))

[nightcityblade]

Hi, I'd like to work on this. I'll submit a focused PR with regression coverage shortly.