def test_missing_aggregation_raises_exception(
      self, use_edges, use_nodes, edges_reducer,
      nodes_reducer):
    """Checks that missing a required aggregation argument raises an error."""
    with self.assertRaisesRegexp(ValueError, "should not be None"):
      blocks.GlobalBlock(
          global_model_fn=self._global_model_fn,
          use_edges=use_edges,
          use_nodes=use_nodes,
          use_globals=False,
          edges_reducer=edges_reducer,
          nodes_reducer=nodes_reducer)