g2.putEdge(N1, N2);

    assertThat(graph).isNotEqualTo(g2);
  }

  // Node/edge sets and node/edge connections are the same, but directedness differs.
  @Test
  public void equivalent_selfLoop_directedVsUndirected() {
    graph.putEdge(N1, N1);

    MutableGraph<Integer> g2 = createGraph(oppositeType(edgeType));
    g2.putEdge(N1, N1);

    assertThat(graph).isNotEqualTo(g2);
  }

    g2.putEdge(N1, N2);

    assertThat(graph).isNotEqualTo(g2);
  }

  // Node/edge sets and node/edge connections are the same, but directedness differs.
  @Test
  public void equivalent_selfLoop_directedVsUndirected() {
    graph.putEdge(N1, N1);

    MutableGraph<Integer> g2 = createGraph(oppositeType(edgeType));
    g2.putEdge(N1, N1);

    assertThat(graph).isNotEqualTo(g2);
  }