.containsExactlyElementsIn(network.edgesConnecting(adjacentNode, node));
      }
    }
  }

  @Override
  @Test
  public void nodes_checkReturnedSetMutability() {
    Set<Integer> nodes = network.nodes();
    assertThrows(UnsupportedOperationException.class, () -> nodes.add(N2));
    addNode(N1);
    assertThat(network.nodes()).containsExactlyElementsIn(nodes);
  }

  @Override
  @Test

      Set<Object> expected = new HashMap<>(cache.asMap()).keySet();
      assertThat(keys).containsExactlyElementsIn(expected);
      assertThat(keys.toArray()).asList().containsExactlyElementsIn(expected);
      assertThat(keys.toArray(new Object[0])).asList().containsExactlyElementsIn(expected);

      new EqualsTester()
          .addEqualityGroup(cache.asMap().keySet(), keys)

    double[] dataset = Doubles.toArray(SIXTEEN_SQUARES_DOUBLES);
    assertThat(median().computeInPlace(dataset)).isWithin(ALLOWED_ERROR).of(SIXTEEN_SQUARES_MEDIAN);
    assertThat(dataset).usingExactEquality().containsExactlyElementsIn(SIXTEEN_SQUARES_DOUBLES);
  }

  public void testQuartiles_index_compute_doubleCollection() {
    assertThat(quartiles().index(1).compute(SIXTEEN_SQUARES_DOUBLES))
        .isWithin(ALLOWED_ERROR)

    double[] dataset = Doubles.toArray(SIXTEEN_SQUARES_DOUBLES);
    assertThat(median().computeInPlace(dataset)).isWithin(ALLOWED_ERROR).of(SIXTEEN_SQUARES_MEDIAN);
    assertThat(dataset).usingExactEquality().containsExactlyElementsIn(SIXTEEN_SQUARES_DOUBLES);
  }

  public void testQuartiles_index_compute_doubleCollection() {
    assertThat(quartiles().index(1).compute(SIXTEEN_SQUARES_DOUBLES))
        .isWithin(ALLOWED_ERROR)

    assertThat(actual.getLowerBounds())
        .asList()
        .containsExactlyElementsIn(asList(expected.getLowerBounds()))
        .inOrder();
    assertThat(actual.getUpperBounds())
        .asList()
        .containsExactlyElementsIn(asList(expected.getUpperBounds()))
        .inOrder();
  }

  private static class WithTypeVariable {

        List<Integer> target = new ArrayList<>(contents);
        target.add(4);
        C addThenFilter = filter(createUnfiltered(target), EVEN);

        assertThat(filterThenAdd).containsExactlyElementsIn(addThenFilter);
      }
    }

    public void testAdd() {
      for (List<Integer> contents : SAMPLE_INPUTS) {
        for (int toAdd = 0; toAdd < 10; toAdd++) {

      Set<Object> expected = new HashMap<>(cache.asMap()).keySet();
      assertThat(keys).containsExactlyElementsIn(expected);
      assertThat(keys.toArray()).asList().containsExactlyElementsIn(expected);
      assertThat(keys.toArray(new Object[0])).asList().containsExactlyElementsIn(expected);

      new EqualsTester()
          .addEqualityGroup(cache.asMap().keySet(), keys)

    ImmutableSortedSet<String> set = ImmutableSortedSet.copyOf(strings);
    sort(strings);
    for (int i = 0; i < strings.length; i++) {
      assertThat(set.headSet(strings[i], true))
          .containsExactlyElementsIn(sortedNumberNames(0, i + 1))
          .inOrder();
    }
  }

  public void testHeadSetExclusive() {
    String[] strings = NUMBER_NAMES.toArray(new String[0]);

    addNode(N1);
    ImmutableSet<Integer> nodes = ImmutableSet.copyOf(graph.nodes());
    assertThat(graphAsMutableGraph.addNode(N1)).isFalse();
    assertThat(graph.nodes()).containsExactlyElementsIn(nodes);
  }

  @Test
  public void removeNode_existingNode() {
    assume().that(graphIsMutable()).isTrue();

    putEdge(N1, N2);
    putEdge(N4, N1);

    }
    List<String> actualKeys = new ArrayList<>();
    multimap.keys().spliterator().forEachRemaining(actualKeys::add);
    assertThat(actualKeys)
        .containsExactlyElementsIn(transform(expectedEntries, Entry::getKey))
        .inOrder();
  }

  public void testEntriesSpliterator() {
    List<Entry<String, Integer>> expectedEntries =
        asList(