Fix #4547. Handle both null inherited predefined types and disable editing predefined types on occurrences which inherit from a type.

src/blenderbim/blenderbim/bim/module/attribute/operator.py

@@ -47,10 +47,18 @@ class EnableEditingAttributes(bpy.types.Operator):
             obj = bpy.data.objects.get(self.obj)
         elif self.obj_type == "Material":
             obj = bpy.data.materials.get(self.obj)
-        oprops = obj.BIMObjectProperties
         props = obj.BIMAttributeProperties
         props.attributes.clear()
 
+        element = tool.Ifc.get_entity(obj)
+        has_inherited_predefined_type = False
+        if not element.is_a("IfcTypeObject") and (element_type := ifcopenshell.util.element.get_type(element)):
+            # Allow for None due to https://github.com/buildingSMART/IFC4.3.x-development/issues/818
+            has_inherited_predefined_type = ifcopenshell.util.element.get_predefined_type(element_type) not in (
+                "NOTDEFINED",
+                None,
+            )
+
         def callback(name, prop, data):
             if name in ("RefLatitude", "RefLongitude"):
                 new = props.attributes.add()
@@ -62,10 +70,11 @@ class EnableEditingAttributes(bpy.types.Operator):
                 new.string_value = "" if new.is_null else json.dumps(data[name])
                 blenderbim.bim.helper.add_attribute_description(new)
                 new.description += " The degrees, minutes and seconds should follow this format : [12,34,56]"
+            if name in ("PredefinedType", "ObjectType") and has_inherited_predefined_type:
+                props.attributes.remove(len(props.attributes) - 1)
+                return True
 
-        blenderbim.bim.helper.import_attributes2(
-            tool.Ifc.get().by_id(oprops.ifc_definition_id), props.attributes, callback=callback
-        )
+        blenderbim.bim.helper.import_attributes2(element, props.attributes, callback=callback)
         props.is_editing_attributes = True
         return {"FINISHED"}
 

src/blenderbim/blenderbim/bim/module/root/data.py

@@ -169,7 +169,8 @@ class IfcClassData:
         if not element:
             return
         if element_type := ifcopenshell.util.element.get_type(element):
-            return ifcopenshell.util.element.get_predefined_type(element_type) != "NOTDEFINED"
+            # Allow for None due to https://github.com/buildingSMART/IFC4.3.x-development/issues/818
+            return ifcopenshell.util.element.get_predefined_type(element_type) not in ("NOTDEFINED", None)
         return False
 
     @classmethod

src/ifcopenshell-python/ifcopenshell/api/attribute/edit_attributes.py

@@ -64,7 +64,8 @@ class Usecase:
                     self.settings["product"].PredefinedType = "USERDEFINED"
             elif hasattr(self.settings["product"], "ObjectType"):
                 relating_type = ifcopenshell.util.element.get_type(self.settings["product"])
-                if relating_type and relating_type.PredefinedType != "NOTDEFINED":
+                # Allow for None due to https://github.com/buildingSMART/IFC4.3.x-development/issues/818
+                if relating_type and relating_type.PredefinedType not in ("NOTDEFINED", None):
                     self.settings["product"].ObjectType = None
                     self.settings["product"].PredefinedType = None
                 elif (