Support auto detection of unit type when adding imperial units

src/ifcopenshell-python/test/api/unit/test_remove_unit.py

@@ -0,0 +1,31 @@
+import test.bootstrap
+import ifcopenshell.api
+
+
+class TestRemoveUnit(test.bootstrap.IFC4):
+    def test_remove_a_single_unit(self):
+        unit = self.file.createIfcContextDependentUnit()
+        ifcopenshell.api.run("unit.remove_unit", self.file, unit=unit)
+        assert len(self.file.by_type("IfcContextDependentUnit")) == 0
+
+    def test_remove_the_only_assigned_unit(self):
+        self.file.createIfcProject()
+        unit = self.file.createIfcContextDependentUnit()
+        ifcopenshell.api.run("unit.assign_unit", self.file, units=[unit])
+        ifcopenshell.api.run("unit.remove_unit", self.file, unit=unit)
+        assert len(self.file.by_type("IfcContextDependentUnit")) == 0
+        assert len(self.file.by_type("IfcUnitAssignment")) == 0
+
+    def test_remove_an_assigned_unit(self):
+        self.file.createIfcProject()
+        unit1 = self.file.createIfcContextDependentUnit()
+        unit2 = self.file.createIfcSIUnit()
+        assignment = ifcopenshell.api.run("unit.assign_unit", self.file, units=[unit1, unit2])
+        ifcopenshell.api.run("unit.remove_unit", self.file, unit=unit1)
+        assert len(self.file.by_type("IfcContextDependentUnit")) == 0
+        assert assignment.Units == (unit2,)
+
+    def test_removing_a_unit_deeply(self):
+        unit = ifcopenshell.api.run("unit.add_conversion_based_unit", self.file, name="foot")
+        ifcopenshell.api.run("unit.remove_unit", self.file, unit=unit)
+        assert len([e for e in self.file]) == 0