From 5fb7e6e375ebe4cc49342f3ef3ebce9a0bc0879f Mon Sep 17 00:00:00 2001
From: Andrej730 <azhilenkov@gmail.com>
Date: Mon, 3 Jun 2024 12:37:56 +0500
Subject: [PATCH] resource.remove_resource - fix issue removing resources in
 ifc2x3

---
 .../api/resource/remove_resource.py           |  5 +++--
 .../test/api/resource/test_remove_resource.py | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)
 create mode 100644 src/ifcopenshell-python/test/api/resource/test_remove_resource.py

diff --git a/src/ifcopenshell-python/ifcopenshell/api/resource/remove_resource.py b/src/ifcopenshell-python/ifcopenshell/api/resource/remove_resource.py
index e5356a9dd9..bf5c46e6f7 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/resource/remove_resource.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/resource/remove_resource.py
@@ -74,8 +74,9 @@ def remove_resource(file: ifcopenshell.file, resource: ifcopenshell.entity_insta
                 file.remove(inverse)
                 if history:
                     ifcopenshell.util.element.remove_deep2(file, history)
-    if settings["resource"].Usage:
-        file.remove(settings["resource"].Usage)
+    # Usage was added in IFC4.
+    if usage := getattr(settings["resource"], "Usage", None):
+        file.remove(usage)
     if settings["resource"].BaseQuantity:
         ifcopenshell.api.run(
             "resource.remove_resource_quantity",
diff --git a/src/ifcopenshell-python/test/api/resource/test_remove_resource.py b/src/ifcopenshell-python/test/api/resource/test_remove_resource.py
new file mode 100644
index 0000000000..514c8bc16f
--- /dev/null
+++ b/src/ifcopenshell-python/test/api/resource/test_remove_resource.py
@@ -0,0 +1,19 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2024 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/>.
+
+# remove_resource tests is partially covered by test_add_resource_quantity.