New utility function for getting ports of an element

src/ifcopenshell-python/ifcopenshell/util/system.py

@@ -34,3 +34,12 @@ def get_element_systems(element):
         ]:
             results.append(rel.RelatingGroup)
     return results
+
+
+def get_ports(element):
+    results = []
+    for rel in getattr(element, "IsNestedBy", []) or []:
+        results.extend([o for o in rel.RelatedObjects if o.is_a("IfcDistributionPort")])
+    for rel in element.HasPorts or []:
+        results.append(rel.RelatingPort)
+    return results

src/ifcopenshell-python/test/util/test_system.py

@@ -45,3 +45,19 @@ class TestGetElementSystems(test.bootstrap.IFC4):
             "system.assign_system", self.file, product=element, system=self.file.createIfcStructuralAnalysisModel()
         )
         assert not subject.get_element_systems(element)
+
+
+class TestGetPorts(test.bootstrap.IFC4):
+    def test_run(self):
+        port = self.file.createIfcDistributionPort()
+        element = ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcChiller")
+        ifcopenshell.api.run("system.assign_port", self.file, element=element, port=port)
+        assert subject.get_ports(element) == [port]
+
+
+class TestGetPortsIFC2X3(test.bootstrap.IFC2X3):
+    def test_run(self):
+        port = self.file.createIfcDistributionPort()
+        element = ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcFlowSegment")
+        ifcopenshell.api.run("system.assign_port", self.file, element=element, port=port)
+        assert subject.get_ports(element) == [port]