Do not cache parametrized models when in the process of parametrizing another model

Viicos · Viicos · commit 712a2573faf0 · 2024-10-24T21:25:15.000+02:00
diff --git a/pydantic/main.py b/pydantic/main.py
@@ -804,8 +804,12 @@ def __class_getitem__(
 
                 submodel = _generics.create_generic_submodel(model_name, origin, args, params)
 
-                # Update cache
-                _generics.set_cached_generic_type(cls, typevar_values, submodel, origin, args)
+                # Cache the generated model *only* if not in the process of parametrizing
+                # another model. In some valid scenarios, we miss the opportunity to cache
+                # it but in some cases this results in `PydanticRecursiveRef` instances left
+                # on `FieldInfo` annotations:
+                if len(_generics.recursively_defined_type_refs()) == 1:
+                    _generics.set_cached_generic_type(cls, typevar_values, submodel, origin, args)
 
         return submodel
 
