The from_pydantic function in Pydantic does not work with a specialized list class. When attempting to convert a specialized list instance, such as workList[WorkModel], an error is raised: ValueError: Not supported workList[types.Work].

Code Example

import strawberry
from typing import TypeVar, List
from pydantic import BaseModel

SI = TypeVar("SI", covariant=True)

class SpecialList(List[SI]):
    pass

class WorkModel(BaseModel):
    name: str

class workList(SpecialList[SI]):
    min_items = 1

class UserModel(BaseModel):
    work: workList[WorkModel]

@strawberry.experimental.pydantic.type(WorkModel)
class Work:
    name: strawberry.auto

@strawberry.experimental.pydantic.type(UserModel)
class User:
    work: strawberry.auto

origin_user = UserModel(
    work=[WorkModel(name="developer"), WorkModel(name="tester")]
)

user = User.from_pydantic(origin_user)

assert user == User(work=[Work(name="developer"), Work(name="tester")])

Expected Behavior

The conversion from the Pydantic model UserModel to the Strawberry model User should work properly, including the conversion of the specialized list workList[WorkModel] to a list of Work instances.

Actual Behavior

An error is raised: ValueError: Not supported tests.experimental.pydantic.test_conversion.test_can_convert_pydantic_type_to_strawberry_with_constrained_list..workList[types.Work].

Additional Context

I encountered this error while working on the orchestrator-core project. The error is similar to the one mentioned in the GitHub reference provided. Here is the relevant code snippet from that reference:

class SubscriptionInstanceList(ConstrainedList, List[SI]):  # type: ignore
    """Shorthand to create constrained lists of product blocks."""

    def __init_subclass__(cls, **kwargs: Any) -> None:
        super().__init_subclass__(**kwargs)

        # Copy generic argument (SI) if not set explicitly
        # This makes a lot of assumptions about the internals of `typing`
        if "__orig_bases__" in cls.__dict__ and cls.__dict__["__orig_bases__"]:
            generic_base_cls = cls.__dict__["__orig_bases__"][0]
            if not hasattr(generic_base_cls, "item_type") and get_args(generic_base_cls):
                cls.item_type = get_args(generic_base_cls)[0]

        # Make sure __args__ is set
        cls.__args__ = (cls.item_type,)