Clean up IfcIndexedColourMap removing representation #4138

Because we wasn't removing colour map, remove_representation was producing orphaned IfcPolygonalFaceSet that were referred by colour map.

src/ifcopenshell-python/ifcopenshell/api/geometry/remove_representation.py

@@ -30,10 +30,13 @@ class Usecase:
         styled_items = set()
         presentation_layer_assignments = set()
         textures = set()
+        colours = set()
         for subelement in self.file.traverse(self.settings["representation"]):
             if subelement.is_a("IfcRepresentationItem"):
                 [styled_items.add(s) for s in subelement.StyledByItem or []]
+                # IfcTesselatedFaceSet inverses
                 [textures.add(t) for t in getattr(subelement, "HasTextures", []) or []]
+                [colours.add(t) for t in getattr(subelement, "HasColours", []) or []]
             elif subelement.is_a("IfcRepresentation"):
                 for inverse in self.file.get_inverse(subelement):
                     if inverse.is_a("IfcPresentationLayerAssignment"):
@@ -42,12 +45,14 @@ class Usecase:
         ifcopenshell.util.element.remove_deep2(
             self.file,
             self.settings["representation"],
-            also_consider=list(styled_items | presentation_layer_assignments),
+            also_consider=list(styled_items | presentation_layer_assignments | colours),
             do_not_delete=self.file.by_type("IfcGeometricRepresentationContext"),
         )
 
         for texture in textures:
             ifcopenshell.util.element.remove_deep2(self.file, texture)
+        for colour in colours:
+            ifcopenshell.util.element.remove_deep2(self.file, colour)
 
         to_delete = getattr(self.file, "to_delete", ())
         for element in styled_items:

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

@@ -100,6 +100,14 @@ class TestRemoveRepresentation(test.bootstrap.IFC4):
         ifcopenshell.api.run("geometry.remove_representation", self.file, representation=representation)
         assert len(self.file.by_type("IfcGeometricRepresentationContext")) == 1
 
+    def test_purging_colour_map(self):
+        item = self.file.createIfcTriangulatedFaceSet()
+        representation = self.file.createIfcShapeRepresentation(Items=[item])
+        colour = self.file.createIfcIndexedColourMap(Colours=self.file.createIfcColourRgbList(), MappedTo=item)
+        ifcopenshell.api.run("geometry.remove_representation", self.file, representation=representation)
+        assert len(self.file.by_type("IfcIndexedColourMap")) == 0
+        assert len(self.file.by_type("IfcColourRgbList")) == 0
+
     def test_purging_texture_coordinates(self):
         item = self.file.createIfcTriangulatedFaceSet()
         representation = self.file.createIfcShapeRepresentation(Items=[item])