assertThat(undirectedMultigraph.edgesConnecting(N1, N2))
        .isEqualTo(ImmutableSet.of(E12, E12_A, E21));
  }

  @Test
  public void createDirected_expectedNodeCount() {
    MutableNetwork<Integer, String> directedGraph =
        NetworkBuilder.directed().expectedNodeCount(NODE_COUNT).build();
    assertThat(directedGraph.addEdge(N1, N2, E12)).isTrue();