That’s an interesting idea, but no we do not consider the return type of decorators when looking for fields.

-Erik

From: Patrick Arminio <patrick.arminio@gmail.com>
Sent: Sunday, March 6, 2022 5:23 PM
To: David Foster <davidfstr@gmail.com>
Cc: Erik De Bonte <Erik.DeBonte@microsoft.com>; typing-sig@python.org
Subject: Re: [Typing-sig] Re: Dataclass Transform draft PEP

Does the PEP/implementation take into account the return type specified in the functions signature?

For example, assuming we had Intersection as a type, would this work?

class HasSomeAttr(typing.Protocol):
    attr: str

@typing.dataclass_transform(
    kw_only_default=True,
    field_descriptors=(model_field, ))
def create_model(
    *,
    init: bool = True,
) -> Callable[[Type[_T]], typing.Intersection[Type[_T], HasSomeAttr]]: ...

--

Patrick Arminio