assertThat(network.edges()).containsExactly("p", "i", "e").inOrder();
    assertThat(network.nodeOrder()).isEqualTo(unordered());
    assertThat(network.nodes()).containsExactly(4, 1, 3);
  }

  // Sorting of user-defined classes

  @Test
  public void customComparator() {
    Comparator<NonComparableSuperClass> comparator =
        new Comparator<NonComparableSuperClass>() {

"2.4 OK"
"2.5 OK"
"2.6 OK"
"2.7 OK"
"2.8 OK"
"2.9 OK"
"3.1 OK"
"3.2 NON-STRICT"
"3.3 NON-STRICT"
"3.4 NON-STRICT"
"3.5 OK"
"3.6 OK"
"3.7 OK"
"4.1.1 OK"
"4.1.2 OK"
"4.1.3 NON-STRICT"
"4.1.4 NON-STRICT"
"4.1.5 OK"
"4.2.1 OK"
"4.2.2 OK"
"4.2.3 NON-STRICT"
"4.2.4 OK"
"4.2.5 OK"
"5.1 OK"
"5.10 OK"
"5.11 OK"
"5.12 OK"
"5.13 OK"
"5.14 OK"
"5.15 OK"