expectedSubgraph.addEdge(N4, N4, E44);

    assertThat(inducedSubgraph(directedGraph, nodeSubset)).isEqualTo(expectedSubgraph);
  }

  @Test
  public void inducedSubgraph_nodeNotInGraph() {
    MutableNetwork<Integer, String> undirectedGraph = NetworkBuilder.undirected().build();

    assertThrows(
        IllegalArgumentException.class,
        () -> inducedSubgraph(undirectedGraph, ImmutableSet.of(N1)));
  }

  @Test