Add api.structural.assign_product, assign_to_building, and api.geometry.add_topology_representation

assign_product creates IfcRelAssignsToProduct linking a structural member to
a physical building element. assign_to_building creates IfcRelServicesBuildings
linking a structural analysis model to a building. add_topology_representation
creates IfcTopologyRepresentation for structural elements, inferring the
representation type from the item class.

Generated with the assistance of an AI coding tool.

src/ifcopenshell-python/test/api/geometry/test_add_topology_representation.py

@@ -0,0 +1,82 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2026 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of IfcOpenShell.
+#
+# IfcOpenShell is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# IfcOpenShell is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
+# This file was generated with the assistance of an AI coding tool.
+
+import ifcopenshell.api.context
+import ifcopenshell.api.geometry
+import ifcopenshell.api.root
+import test.bootstrap
+
+
+class TestAddTopologyRepresentation(test.bootstrap.IFC4):
+    def setup_context(self):
+        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
+        model = ifcopenshell.api.context.add_context(self.file, context_type="Model")
+        return ifcopenshell.api.context.add_context(
+            self.file,
+            context_type="Model",
+            context_identifier="Reference",
+            target_view="GRAPH_VIEW",
+            parent=model,
+        )
+
+    def test_creates_topology_representation(self):
+        context = self.setup_context()
+        face = self.file.create_entity("IfcFaceSurface")
+        rep = ifcopenshell.api.geometry.add_topology_representation(self.file, context=context, item=face)
+        assert rep.is_a("IfcTopologyRepresentation")
+        assert rep.ContextOfItems == context
+        assert face in rep.Items
+
+    def test_infers_face_representation_type(self):
+        context = self.setup_context()
+        face = self.file.create_entity("IfcFaceSurface")
+        rep = ifcopenshell.api.geometry.add_topology_representation(self.file, context=context, item=face)
+        assert rep.RepresentationType == "Face"
+
+    def test_infers_edge_representation_type(self):
+        context = self.setup_context()
+        edge = self.file.create_entity("IfcEdge")
+        rep = ifcopenshell.api.geometry.add_topology_representation(self.file, context=context, item=edge)
+        assert rep.RepresentationType == "Edge"
+
+    def test_defaults_representation_identifier_to_context_identifier(self):
+        context = self.setup_context()
+        face = self.file.create_entity("IfcFaceSurface")
+        rep = ifcopenshell.api.geometry.add_topology_representation(self.file, context=context, item=face)
+        assert rep.RepresentationIdentifier == context.ContextIdentifier
+
+    def test_custom_representation_identifier(self):
+        context = self.setup_context()
+        face = self.file.create_entity("IfcFaceSurface")
+        rep = ifcopenshell.api.geometry.add_topology_representation(
+            self.file, context=context, item=face, representation_identifier="Body"
+        )
+        assert rep.RepresentationIdentifier == "Body"
+
+    def test_custom_representation_type_overrides_inferred(self):
+        context = self.setup_context()
+        face = self.file.create_entity("IfcFaceSurface")
+        rep = ifcopenshell.api.geometry.add_topology_representation(
+            self.file, context=context, item=face, representation_type="Undefined"
+        )
+        assert rep.RepresentationType == "Undefined"
+
+
+class TestAddTopologyRepresentationIFC2X3(test.bootstrap.IFC2X3, TestAddTopologyRepresentation):
+    pass

src/ifcopenshell-python/test/api/structural/test_assign_product.py

@@ -0,0 +1,56 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2026 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of IfcOpenShell.
+#
+# IfcOpenShell is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# IfcOpenShell is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
+# This file was generated with the assistance of an AI coding tool.
+
+import ifcopenshell.api.root
+import ifcopenshell.api.structural
+import test.bootstrap
+
+
+class TestAssignProduct(test.bootstrap.IFC4):
+    def test_creating_a_new_relationship(self):
+        member = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcStructuralSurfaceMember")
+        wall = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
+        rel = ifcopenshell.api.structural.assign_product(self.file, relating_product=member, related_object=wall)
+        assert rel.is_a("IfcRelAssignsToProduct")
+        assert rel.RelatingProduct == member
+        assert wall in rel.RelatedObjects
+
+    def test_adding_a_second_object_to_an_existing_relationship(self):
+        member = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcStructuralSurfaceMember")
+        wall1 = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
+        wall2 = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
+        rel1 = ifcopenshell.api.structural.assign_product(self.file, relating_product=member, related_object=wall1)
+        rel2 = ifcopenshell.api.structural.assign_product(self.file, relating_product=member, related_object=wall2)
+        assert rel1 == rel2
+        assert len(self.file.by_type("IfcRelAssignsToProduct")) == 1
+        assert wall1 in rel1.RelatedObjects
+        assert wall2 in rel1.RelatedObjects
+
+    def test_does_not_duplicate_an_existing_assignment(self):
+        member = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcStructuralSurfaceMember")
+        wall = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
+        ifcopenshell.api.structural.assign_product(self.file, relating_product=member, related_object=wall)
+        ifcopenshell.api.structural.assign_product(self.file, relating_product=member, related_object=wall)
+        assert len(self.file.by_type("IfcRelAssignsToProduct")) == 1
+        rels = self.file.by_type("IfcRelAssignsToProduct")
+        assert len(rels[0].RelatedObjects) == 1
+
+
+class TestAssignProductIFC2X3(test.bootstrap.IFC2X3, TestAssignProduct):
+    pass

src/ifcopenshell-python/test/api/structural/test_assign_to_building.py

@@ -0,0 +1,62 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2026 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of IfcOpenShell.
+#
+# IfcOpenShell is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# IfcOpenShell is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
+# This file was generated with the assistance of an AI coding tool.
+
+import ifcopenshell.api.root
+import ifcopenshell.api.structural
+import test.bootstrap
+
+
+class TestAssignToBuilding(test.bootstrap.IFC4):
+    def test_creating_a_new_relationship(self):
+        model = ifcopenshell.api.structural.add_structural_analysis_model(self.file)
+        building = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcBuilding")
+        rel = ifcopenshell.api.structural.assign_to_building(
+            self.file, structural_analysis_model=model, building=building
+        )
+        assert rel.is_a("IfcRelServicesBuildings")
+        assert rel.RelatingSystem == model
+        assert building in rel.RelatedBuildings
+
+    def test_adding_a_second_building_to_an_existing_relationship(self):
+        model = ifcopenshell.api.structural.add_structural_analysis_model(self.file)
+        building1 = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcBuilding")
+        building2 = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcBuilding")
+        rel1 = ifcopenshell.api.structural.assign_to_building(
+            self.file, structural_analysis_model=model, building=building1
+        )
+        rel2 = ifcopenshell.api.structural.assign_to_building(
+            self.file, structural_analysis_model=model, building=building2
+        )
+        assert rel1 == rel2
+        assert len(self.file.by_type("IfcRelServicesBuildings")) == 1
+        assert building1 in rel1.RelatedBuildings
+        assert building2 in rel1.RelatedBuildings
+
+    def test_does_not_duplicate_an_existing_assignment(self):
+        model = ifcopenshell.api.structural.add_structural_analysis_model(self.file)
+        building = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcBuilding")
+        ifcopenshell.api.structural.assign_to_building(self.file, structural_analysis_model=model, building=building)
+        ifcopenshell.api.structural.assign_to_building(self.file, structural_analysis_model=model, building=building)
+        assert len(self.file.by_type("IfcRelServicesBuildings")) == 1
+        rels = self.file.by_type("IfcRelServicesBuildings")
+        assert len(rels[0].RelatedBuildings) == 1
+
+
+class TestAssignToBuildingIFC2X3(test.bootstrap.IFC2X3, TestAssignToBuilding):
+    pass