Fixed typo in control.assign_control, added tests

src/ifcopenshell-python/ifcopenshell/api/control/assign_control.py

@@ -40,8 +40,9 @@ class Usecase:
         :type relating_control: ifcopenshell.entity_instance.entity_instance
         :param related_object: The IfcObjectDefinition that is being controlled
         :type related_object: ifcopenshell.entity_instance.entity_instance
-        :return: The newly created IfcRelAssignsToControl
+        :return: The newly created IfcRelAssignsToControl. If relationship already
-        :rtype: ifcopenshell.entity_instance.entity_instance
+            existed before and wasn't changed then returns None.
+        :rtype: ifcopenshell.entity_instance.entity_instance, None
 
         Example:
 
@@ -76,7 +77,7 @@ class Usecase:
         if self.settings["related_object"].HasAssignments:
             for assignment in self.settings["related_object"].HasAssignments:
                 if (
-                    assignment.is_a("IfclRelAssignsToControl")
+                    assignment.is_a("IfcRelAssignsToControl")
                     and assignment.RelatingControl == self.settings["relating_control"]
                 ):
                     return
@@ -86,6 +87,8 @@ class Usecase:
             controls = self.settings["relating_control"].Controls[0]
 
         if controls:
+            if self.settings["related_object"] in controls.RelatedObjects:
+                return
             related_objects = set(controls.RelatedObjects)
             related_objects.add(self.settings["related_object"])
             controls.RelatedObjects = list(related_objects)

src/ifcopenshell-python/test/api/control/test_assign_control.py

@@ -0,0 +1,50 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2022 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/>.
+
+import test.bootstrap
+import ifcopenshell.api
+
+
+class TestAssignControl(test.bootstrap.IFC4):
+    def test_run(self):
+        wall = self.file.createIfcWall()
+        control = ifcopenshell.api.run("cost.add_cost_schedule", self.file)
+
+        # simple assignment
+        relation = ifcopenshell.api.run(
+            "control.assign_control", self.file, relating_control=control, related_object=wall
+        )
+        assert len(self.file.by_type("IfcRelAssignsToControl")) == 1
+        assert relation.RelatingControl == control
+        assert relation.RelatedObjects == (wall,)
+
+        # trying to establish existing relationship
+        relation = ifcopenshell.api.run(
+            "control.assign_control", self.file, relating_control=control, related_object=wall
+        )
+        assert relation is None
+
+        # assigning same control to another object
+        wall1 = self.file.createIfcWall()
+        relation = ifcopenshell.api.run(
+            "control.assign_control", self.file, relating_control=control, related_object=wall1
+        )
+        assert relation is not None
+        assert len(self.file.by_type("IfcRelAssignsToControl")) == 1
+        assert relation.RelatingControl == control
+        assert set(relation.RelatedObjects) == set((wall, wall1))

src/ifcopenshell-python/test/api/control/test_unassign_control.py

@@ -0,0 +1,43 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2022 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/>.
+
+import test.bootstrap
+import ifcopenshell.api
+
+
+class TestUnassignControl(test.bootstrap.IFC4):
+    def test_run(self):
+        wall = self.file.createIfcWall()
+        control = ifcopenshell.api.run("cost.add_cost_schedule", self.file)
+
+        # assign and unassign
+        relation = ifcopenshell.api.run(
+            "control.assign_control", self.file, relating_control=control, related_object=wall
+        )
+        ifcopenshell.api.run("control.unassign_control", self.file, relating_control=control, related_object=wall)
+        assert len(self.file.by_type("IfcRelAssignsToControl")) == 0
+
+        # 1 control 2 related objects
+        wall1 = self.file.createIfcWall()
+        relation = ifcopenshell.api.run(
+            "control.assign_control", self.file, relating_control=control, related_object=wall
+        )
+        ifcopenshell.api.run("control.assign_control", self.file, relating_control=control, related_object=wall1)
+        ifcopenshell.api.run("control.unassign_control", self.file, relating_control=control, related_object=wall1)
+        assert len(self.file.by_type("IfcRelAssignsToControl")) == 1
+        assert relation.RelatedObjects == (wall,)