assertThat(network.edges()).containsExactly("i", "e", "p").inOrder();
    assertThat(network.nodeOrder()).isEqualTo(ElementOrder.insertion()); // default
  }

  @Test
  public void edgeOrder_natural() {
    MutableNetwork<Integer, String> network =
        NetworkBuilder.directed().edgeOrder(ElementOrder.<String>natural()).build();

    addEdges(network);