Use isodate to parse iso durations #2783

Related #6585

Co-Authored-By: sboddy <12862430+sboddy@users.noreply.github.com>

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

@@ -0,0 +1,27 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2021 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 pytest
+import test.bootstrap
+import ifcopenshell.util.date as subject
+
+
+class TestIsoDuration:
+    def test_run(self):
+        assert subject.readable_ifc_duration("P2Y3M1W4DT5H45M30S") == "2 y 3 m 1 w 4 d 5 h 45 m 30 s"
+        assert subject.readable_ifc_duration("P2Y3MT30S") == "2 y 3 m 30 s"