Monkeypatch rx.Base for python3.14 compatible annotations

Author: masenf

reflex/base.py

@@ -5,7 +5,9 @@
 if find_spec("pydantic") and find_spec("pydantic.v1"):
     from pydantic.v1 import BaseModel
 
-    class Base(BaseModel):
+    from reflex.utils.compat import ModelMetaclassLazyAnnotations
+
+    class Base(BaseModel, metaclass=ModelMetaclassLazyAnnotations):
         """The base class subclassed by all Reflex classes.
 
         This class wraps Pydantic and provides common methods such as

reflex/utils/compat.py

@@ -31,6 +31,31 @@ async def windows_hot_reload_lifespan_hack():
         pass
 
 
+if find_spec("pydantic") and find_spec("pydantic.v1"):
+    from pydantic.v1.main import ModelMetaclass
+
+    class ModelMetaclassLazyAnnotations(ModelMetaclass):
+        """Compatibility metaclass to resolve python3.14 style lazy annotations."""
+
+        def __new__(mcs, name: str, bases: tuple, namespace: dict, **kwargs):
+            """Resolve python3.14 style lazy annotations before passing off to pydantic v1.
+
+            Args:
+                name: The class name.
+                bases: The base classes.
+                namespace: The class namespace.
+                **kwargs: Additional keyword arguments.
+
+            Returns:
+                The created class.
+            """
+            if (_anotate := namespace.get("__annotate_func__")) is not None:
+                namespace["__annotations__"] = _anotate(0)
+            return super().__new__(mcs, name, bases, namespace, **kwargs)
+else:
+    ModelMetaclassLazyAnnotations = type  # type: ignore[assignment]
+
+
 def sqlmodel_field_has_primary_key(field_info: "FieldInfo") -> bool:
     """Determines if a field is a primary.