Make sure tests pass in all supported python versions

Author: mbsantiago

sqlmodel/main.py

@@ -1,4 +1,7 @@
+from __future__ import annotations
+
 import ipaddress
+import sys
 import uuid
 import weakref
 from datetime import date, datetime, time, timedelta
@@ -22,8 +25,6 @@
     TypeVar,
     Union,
     cast,
-    get_args,
-    get_origin,
 )
 
 from pydantic import BaseModel
@@ -45,6 +46,11 @@
 from .sql.sqltypes import GUID, AutoString
 from .typing import SQLModelConfig
 
+if sys.version_info >= (3, 8):
+    from typing import get_args, get_origin
+else:
+    from typing_extensions import get_args, get_origin
+
 _T = TypeVar("_T")
 NoArgAnyCallable = Callable[[], Any]
 NoneType = type(None)
@@ -61,7 +67,6 @@ def __dataclass_transform__(
 
 
 class FieldInfo(PydanticFieldInfo):
-
     nullable: Union[bool, PydanticUndefinedType]
 
     def __init__(self, default: Any = PydanticUndefined, **kwargs: Any) -> None:
@@ -401,7 +406,7 @@ def __init__(
 
 
 def get_sqlalchemy_type(field: FieldInfo) -> Any:
-    type_: type | None = field.annotation
+    type_: Optional[type] = field.annotation
 
     # Resolve Optional fields
     if type_ is not None and get_origin(type_) is Union:
@@ -486,7 +491,7 @@ def get_column_from_field(field: FieldInfo) -> Column:  # type: ignore
         "index": index,
         "unique": unique,
     }
-    sa_default: PydanticUndefinedType | Callable[[], Any] = PydanticUndefined
+    sa_default: Union[PydanticUndefinedType, Callable[[], Any]] = PydanticUndefined
     if field.default_factory:
         sa_default = field.default_factory
     elif field.default is not PydanticUndefined:
@@ -531,7 +536,7 @@ def __new__(cls, *args: Any, **kwargs: Any) -> Any:
     def __init__(__pydantic_self__, **data: Any) -> None:
         old_dict = __pydantic_self__.__dict__.copy()
         super().__init__(**data)
-        __pydantic_self__.__dict__ = old_dict | __pydantic_self__.__dict__
+        __pydantic_self__.__dict__ = {**old_dict, **__pydantic_self__.__dict__}
         non_pydantic_keys = data.keys() - __pydantic_self__.model_fields
         for key in non_pydantic_keys:
             if key in __pydantic_self__.__sqlmodel_relationships__:
@@ -560,12 +565,12 @@ def __tablename__(cls) -> str:
 
     @classmethod
     def model_validate(
-        cls: type[_TSQLModel],
+        cls: Type[_TSQLModel],
         obj: Any,
         *,
-        strict: bool | None = None,
-        from_attributes: bool | None = None,
-        context: dict[str, Any] | None = None,
+        strict: Optional[bool] = None,
+        from_attributes: Optional[bool] = None,
+        context: Optional[Dict[str, Any]] = None,
     ) -> _TSQLModel:
         # Somehow model validate doesn't call __init__ so it would remove our init logic
         validated = super().model_validate(
@@ -590,7 +595,9 @@ def model_validate(
 
 
 def _is_field_noneable(field: FieldInfo) -> bool:
-    if not isinstance(field.nullable, PydanticUndefinedType):
+    if hasattr(field, "nullable") and not isinstance(
+        field.nullable, PydanticUndefinedType
+    ):
         return field.nullable
     if not field.is_required():
         default = getattr(field, "original_default", field.default)