@app.get("/a")
async def a(dep: Dep[A]):
    return {"cls": dep.__class__.__name__}


@app.get("/b")
async def b(dep: Dep[B]):
    return {"cls": dep.__class__.__name__}


client = TestClient(app)


def test_generic_parameterless_depends():
    response = client.get("/a")
    assert response.status_code == 200, response.text
    assert response.json() == {"cls": "A"}

    response = client.get("/b")

RequestErrorModel: Type[BaseModel] = create_model("Request")
WebSocketErrorModel: Type[BaseModel] = create_model("WebSocket")


class FastAPIError(RuntimeError):
    """
    A generic, FastAPI-specific error.
    """


class ValidationException(Exception):
    def __init__(self, errors: Sequence[Any]) -> None:
        self._errors = errors

    def errors(self) -> Sequence[Any]:

                Read more in the
                [FastAPI docs for `lifespan`](https://fastapi.tiangolo.com/advanced/events/).
                """
            ),
        ] = None,
        # the generic to Lifespan[AppType] is the type of the top level application
        # which the router cannot know statically, so we use typing.Any
        lifespan: Annotated[
            Optional[Lifespan[Any]],
            Doc(

            with_info_plain_validator_function as with_info_plain_validator_function,
        )
    except ImportError:  # pragma: no cover
        from pydantic_core.core_schema import (
            general_plain_validator_function as with_info_plain_validator_function,  # noqa: F401
        )

    Required = PydanticUndefined
    Undefined = PydanticUndefined
    UndefinedType = PydanticUndefinedType