improve types -> make queryset generic

ormar/models/__init__.py

@@ -6,7 +6,7 @@ ass well as vast number of helper functions for pydantic, sqlalchemy and relatio
 
 from ormar.models.newbasemodel import NewBaseModel  # noqa I100
 from ormar.models.model_row import ModelRow  # noqa I100
-from ormar.models.model import Model  # noqa I100
+from ormar.models.model import Model, T  # noqa I100
 from ormar.models.excludable import ExcludableItems  # noqa I100
 
-__all__ = ["NewBaseModel", "Model", "ModelRow", "ExcludableItems"]
+__all__ = ["NewBaseModel", "Model", "ModelRow", "ExcludableItems", "T"]

ormar/models/helpers/relations.py

@@ -117,7 +117,7 @@ def register_reverse_model_fields(model_field: "ForeignKeyField") -> None:
         register_through_shortcut_fields(model_field=model_field)
         adjust_through_many_to_many_model(model_field=model_field)
     else:
-        model_field.to.Meta.model_fields[related_name] = ForeignKey(
+        model_field.to.Meta.model_fields[related_name] = ForeignKey(  # type: ignore
             model_field.owner,
             real_name=related_name,
             virtual=True,

ormar/models/helpers/sqlalchemy.py

@@ -26,14 +26,14 @@ def adjust_through_many_to_many_model(model_field: "ManyToManyField") -> None:
     """
     parent_name = model_field.default_target_field_name()
     child_name = model_field.default_source_field_name()
-
-    model_field.through.Meta.model_fields[parent_name] = ormar.ForeignKey(
+    model_fields = model_field.through.Meta.model_fields
+    model_fields[parent_name] = ormar.ForeignKey(  # type: ignore
         model_field.to,
         real_name=parent_name,
         ondelete="CASCADE",
         owner=model_field.through,
     )
-    model_field.through.Meta.model_fields[child_name] = ormar.ForeignKey(
+    model_fields[child_name] = ormar.ForeignKey(  # type: ignore
         model_field.owner,
         real_name=child_name,
         ondelete="CASCADE",

ormar/models/metaclass.py

@@ -18,6 +18,7 @@ from sqlalchemy.sql.schema import ColumnCollectionConstraint
 
 import ormar  # noqa I100
 from ormar import ModelDefinitionError  # noqa I100
+from ormar.exceptions import ModelError
 from ormar.fields import BaseField
 from ormar.fields.foreign_key import ForeignKeyField
 from ormar.fields.many_to_many import ManyToManyField
@@ -44,6 +45,7 @@ from ormar.signals import Signal, SignalEmitter
 
 if TYPE_CHECKING:  # pragma no cover
     from ormar import Model
+    from ormar.models import T
 
 CONFIG_KEY = "Config"
 PARSED_FIELDS_KEY = "__parsed_fields__"
@@ -545,6 +547,15 @@ class ModelMetaclass(pydantic.main.ModelMetaclass):
                         field_name=field_name, model=new_model
                     )
                 new_model.Meta.alias_manager = alias_manager
-                new_model.objects = QuerySet(new_model)
 
         return new_model
+
+    @property
+    def objects(cls: Type["T"]) -> "QuerySet[T]":  # type: ignore
+        if cls.Meta.requires_ref_update:
+            raise ModelError(
+                f"Model {cls.get_name()} has not updated "
+                f"ForwardRefs. \nBefore using the model you "
+                f"need to call update_forward_refs()."
+            )
+        return QuerySet(model_cls=cls)

ormar/models/model.py

@@ -15,8 +15,6 @@ from ormar.models import NewBaseModel  # noqa I100
 from ormar.models.metaclass import ModelMeta
 from ormar.models.model_row import ModelRow
 
-if TYPE_CHECKING:  # pragma nocover
-    from ormar import QuerySet
 
 T = TypeVar("T", bound="Model")
 
@@ -25,7 +23,6 @@ class Model(ModelRow):
     __abstract__ = False
     if TYPE_CHECKING:  # pragma nocover
         Meta: ModelMeta
-        objects: "QuerySet"
 
     def __repr__(self) -> str:  # pragma nocover
         _repr = {k: getattr(self, k) for k, v in self.Meta.model_fields.items()}