def test_no_input_raises_exception(self):
    """Checks that receiving no input raises an exception."""
    with self.assertRaisesRegex(ValueError, "At least one of "):
      blocks.EdgeBlock(
          edge_model_fn=self._edge_model_fn,
          use_edges=False,
          use_receiver_nodes=False,
          use_sender_nodes=False,
          use_globals=False)
Checks that receiving no input raises an exception.
graph_nets/tests_tf2/blocks_test.py