def test_add_already_added(self):
        prio_set_list = event._PrioritizedSetList()
        obj = object()
        prio_set_list.add(0, obj)

        with pytest.raises(ValueError) as excinfo:
            prio_set_list.add(0, obj)
        excinfo.match(r"has already been added")

        with pytest.raises(ValueError) as excinfo:
            prio_set_list.add(1, obj)
        excinfo.match(r"has already been added")
def on_select_row(self, treeview=None):
        """When a row is selected, displays the corresponding editing panel

        @var treeview: not used
        """
        self.dialog.on_backend_selected(self.get_selected_backend_id())