Add feature to get parent of a particular IFC class

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

@@ -1234,7 +1234,9 @@ def get_controls(element: ifcopenshell.entity_instance) -> Generator[ifcopenshel
             yield rel.RelatingControl
 
 
-def get_parent(element: ifcopenshell.entity_instance) -> Union[ifcopenshell.entity_instance, None]:
+def get_parent(
+    element: ifcopenshell.entity_instance, ifc_class: Optional[str] = None
+) -> Union[ifcopenshell.entity_instance, None]:
     """Get the parent in the spatial heirarchy
 
     IFC features a spatial hierarchy tree of all objects. Each spatial element
@@ -1251,6 +1253,8 @@ def get_parent(element: ifcopenshell.entity_instance) -> Union[ifcopenshell.enti
     - Voiding: the opening voids another physical element, such as a hole in a wall
 
     :param element: Any physical or spatial element in the tree
+    :param ifc_class: Optionally filter the type of parent you're after. For
+        example, you may be after the storey, not a space.
     :return: Its parent. This must exist for any valid file, or None if we've reached the IfcProject.
 
     Example:
@@ -1260,7 +1264,7 @@ def get_parent(element: ifcopenshell.entity_instance) -> Union[ifcopenshell.enti
         element = file.by_type("IfcWall")[0]
         parent = ifcopenshell.util.element.get_parent(element)
     """
-    return (
+    parent = (
         get_container(element, should_get_direct=True)
         or get_aggregate(element)
         or get_nest(element)
@@ -1268,6 +1272,16 @@ def get_parent(element: ifcopenshell.entity_instance) -> Union[ifcopenshell.enti
         or get_voided_element(element)
     )
 
+    if not ifc_class:
+        return parent
+
+    while parent:
+        if parent.is_a(ifc_class):
+            return parent
+        parent = get_parent(parent)
+
+    return None
+
 
 def get_filled_void(element: ifcopenshell.entity_instance) -> Union[ifcopenshell.entity_instance, None]:
     """If the element is filling a void, get the void

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

@@ -440,13 +440,13 @@ def _get_element_value(element: ifcopenshell.entity_instance, keys: list[str]) -
         elif key == "container":
             value = ifcopenshell.util.element.get_container(value)
         elif key == "space":
-            value = ifcopenshell.util.element.get_container(value, ifc_class="IfcSpace")
+            value = ifcopenshell.util.element.get_parent(value, ifc_class="IfcSpace")
         elif key == "storey":
-            value = ifcopenshell.util.element.get_container(value, ifc_class="IfcBuildingStorey")
+            value = ifcopenshell.util.element.get_parent(value, ifc_class="IfcBuildingStorey")
         elif key == "building":
-            value = ifcopenshell.util.element.get_container(value, ifc_class="IfcBuilding")
+            value = ifcopenshell.util.element.get_parent(value, ifc_class="IfcBuilding")
         elif key == "site":
-            value = ifcopenshell.util.element.get_container(value, ifc_class="IfcSite")
+            value = ifcopenshell.util.element.get_parent(value, ifc_class="IfcSite")
         elif key == "parent":
             value = ifcopenshell.util.element.get_parent(value)
         elif key in ("types", "occurrences"):

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

@@ -38,6 +38,7 @@ import ifcopenshell.api.sequence
 import ifcopenshell.api.spatial
 import ifcopenshell.api.style
 import ifcopenshell.api.type
+import ifcopenshell.api.feature
 import ifcopenshell.guid
 import ifcopenshell.util.element as subject
 import test.bootstrap
@@ -891,6 +892,35 @@ class TestGetlayers(test.bootstrap.IFC4, TestGetlayersIFC2X3):
         assert subject.get_layers(self.file, element) == [layer]
 
 
+class TestGetParentIFC4(test.bootstrap.IFC4):
+    def test_getting_the_parent_of_an_element(self):
+        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
+        building = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcBuilding")
+        ifcopenshell.api.spatial.assign_container(self.file, products=[element], relating_structure=building)
+        assert subject.get_parent(element) == building
+
+    def test_getting_the_specific_parent_of_an_element(self):
+        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
+        building = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcBuilding")
+        storey = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcBuildingStorey")
+        ifcopenshell.api.aggregate.assign_object(self.file, products=[storey], relating_object=building)
+        ifcopenshell.api.spatial.assign_container(self.file, products=[element], relating_structure=storey)
+        assert subject.get_parent(element, ifc_class="IfcBuilding") == building
+        assert subject.get_parent(element, ifc_class="IfcSite") == None
+
+    def test_getting_the_specific_parent_of_an_element_via_voiding(self):
+        wall = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
+        building = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcBuilding")
+        ifcopenshell.api.spatial.assign_container(self.file, products=[wall], relating_structure=building)
+        opening = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcOpeningElement")
+        ifcopenshell.api.feature.add_feature(self.file, feature=opening, element=wall)
+        window = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWindow")
+        ifcopenshell.api.feature.add_filling(self.file, opening=opening, element=window)
+        assert subject.get_parent(window, ifc_class="IfcWall") == wall
+        assert subject.get_parent(window, ifc_class="IfcBuilding") == building
+        assert subject.get_parent(window, ifc_class="IfcSite") == None
+
+
 class TestGetContainerIFC4(test.bootstrap.IFC4):
     def test_getting_the_spatial_container_of_an_element(self):
         element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")