root.copy_class to support copying ports in ifc2x3

src/ifcopenshell-python/ifcopenshell/api/root/copy_class.py

@@ -86,13 +86,29 @@ class Usecase:
                 inverse.RelatedObjects = [to_element]
                 pset = ifcopenshell.util.element.copy_deep(self.file, inverse.RelatingPropertyDefinition)
                 inverse.RelatingPropertyDefinition = pset
-            elif inverse.is_a("IfcRelNests") and inverse.RelatingObject == from_element:
+            elif (
+                inverse.is_a("IfcRelNests")
+                and inverse.RelatingObject == from_element
+                or inverse.is_a("IfcRelConnectsPortToElement")
+                and inverse.RelatedElement == from_element
+            ):
+                # IfcRelConnectsPortToElement was used in IFC2X3
+                if inverse.is_a("IfcRelNests"):
                     ports = [e for e in inverse.RelatedObjects if e.is_a("IfcDistributionPort")]
-                if ports:
+                else:  # IfcRelConnectsPortToElement
+                    ports = [inverse.RelatingPort]
+                if not ports:
+                    continue
                 new_ports = [ifcopenshell.api.run("root.copy_class", self.file, product=p) for p in ports]
                 inverse = ifcopenshell.util.element.copy(self.file, inverse)
+
+                if inverse.is_a("IfcRelNests"):
                     inverse.RelatingObject = to_element
                     inverse.RelatedObjects = new_ports
+                else:
+                    inverse.RelatedElement = to_element
+                    inverse.RelatingPort = new_ports[0]
+
                 for port in new_ports:
                     ifcopenshell.api.run("system.unassign_port", self.file, element=from_element, port=port)
                     matrix = ifcopenshell.util.placement.get_local_placement(port.ObjectPlacement)

src/ifcopenshell-python/test/api/root/test_copy_class.py

@@ -232,3 +232,15 @@ class TestCopyClass(test.bootstrap.IFC4):
         new = ifcopenshell.api.run("root.copy_class", self.file, product=element)
         assert len(self.file.by_type("IfcRelAssignsToGroup")) == 1
         assert new.HasAssignments[0].RelatingGroup == group
+
+
+class TestCopyClassIFC2X3(test.bootstrap.IFC2X3):
+    def test_copying_distribution_ports_bug(self):
+        element = ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcFlowTerminal")
+        port = ifcopenshell.api.run("system.add_port", self.file)
+        ifcopenshell.api.run("system.assign_port", self.file, element=element, port=port)
+        new = ifcopenshell.api.run("root.copy_class", self.file, product=element)
+        new_ports = ifcopenshell.util.system.get_ports(new)
+        assert port not in new_ports
+        assert new_ports[0].is_a("IfcDistributionPort")
+        assert ifcopenshell.util.system.get_ports(element) == [port]