def test_iadd(self, evt):
        rval = event.ReturnValue(append_events=[evt])
        rval2 = event.ReturnValue(eat=True, append_events=[evt])
        rset = event.ResultSet()

        rset += rval
        rset += rval2
        rset += None
        assert rset.eat
        assert rset.append_events == [evt, evt]
def _on_item_widget_size_allocate(self, item_widget, allocation, item):
    if item in self._items_allocations:
      self._update_width(allocation.width - self._items_allocations[item].width)
      self._update_height(allocation.height - self._items_allocations[item].height)
    else:
      self._update_width(allocation.width)
      self._update_height(allocation.height + self._item_spacing)