Seemingly incorrect type error when classes/functions are reordered

[injust]

I have this piece of code, which type checks fine:

import datetime as dt
from enum import Enum, auto
from typing import Any, Self

from attrs import define, field


@define
class Foo:
    one: dt.datetime = field(converter=[dt.datetime.fromisoformat])

    @classmethod
    def from_json(cls, data: dict[str, Any]) -> Self:
        return cls(**data)


@define
class Bar:
    class Tag(Enum):
        THREE = auto()

    two: Foo = field(converter=Foo.from_json)


def unused() -> set[Bar.Tag]:
    return set()

---

If I add from __future__ import annotations and then reorder unused() before both classes like so:

from __future__ import annotations

import datetime as dt
from enum import Enum, auto
from typing import Any, Self

from attrs import define, field


def unused() -> set[Bar.Tag]:
    return set()


@define
class Foo:
    one: dt.datetime = field(converter=[dt.datetime.fromisoformat])

    @classmethod
    def from_json(cls, data: dict[str, Any]) -> Self:
        return cls(**data)


@define
class Bar:
    class Tag(Enum):
        THREE = auto()

    two: Foo = field(converter=Foo.from_json)

pyright reports these errors:

/Users/jsu/code/bug/repro.py
  /Users/jsu/code/bug/repro.py:16:24 - error: No overloads for "field" match the provided arguments (reportCallIssue)
  /Users/jsu/code/bug/repro.py:16:40 - error: Argument of type "list[(date_string: str, /) -> datetime]" cannot be assigned to parameter "converter" of type "_ConverterType | list[_ConverterType] | tuple[_ConverterType] | None" in function "field"
    Type "list[(date_string: str, /) -> datetime]" is not assignable to type "_ConverterType | list[_ConverterType] | tuple[_ConverterType] | None"
      Type "list[(date_string: str, /) -> datetime]" is not assignable to type "_CallableConverterType"
      "list[(date_string: str, /) -> datetime]" is not assignable to "Converter[Any, Any]"
      "list[(date_string: str, /) -> datetime]" is not assignable to "list[_ConverterType]"
        Type parameter "_T@list" is invariant, but "(date_string: str, /) -> datetime" is not the same as "_ConverterType"
        Consider switching from "list" to "Sequence" which is covariant
      "list[(date_string: str, /) -> datetime]" is not assignable to "tuple[_ConverterType]"
      "list[(date_string: str, /) -> datetime]" is not assignable to "None" (reportArgumentType)
2 errors, 0 warnings, 0 informations 

Which doesn't make sense to me -- the arguments to field() haven't changed at all.

---

This is my environment:

Package           Version
----------------- -------
attrs             24.3.0
nodeenv           1.9.1
pyright           1.1.390
typing-extensions 4.12.2

[erictraut]

I'm not able to repro the problem as reported. For me, pyright 1.1.390 reports the same error for both pieces of code above.

Can you please confirm that you are able to repro a difference between the two?

Order dependencies like this typically hint at a circular dependency between types in your code. In such cases, pyright needs to break the cycle by choosing an arbitrary point in the cycle to begin evaluation. Depending on where it starts the evaluation, this can lead to different errors because of partially-evaluated type information. However, I don't see any circularity in your code example. Perhaps you over-simplified the code when you were creating the sample?

[injust]

I re-tested in a new Python 3.13.1 venv (by copying the code from this discussion) and I can still reproduce the issue.

The example code I provided is pretty true to the original. There is definitely no circular dependency in the types.

[erictraut]

OK, thanks. I had a slightly older version of attrs installed. With the latest version, I'm able to repro this. Apologies for my initial oversight.

I've checked in a fix, and it will be included in the next release of pyright.

[injust]

Thank you!