@Override
        public int compare(Entry<String, Integer> left, Entry<String, Integer> right) {
          return left.getKey().compareTo(right.getKey());
        }
      }.sortedCopy(insertionOrder);
    }

    @Override
    public List<Entry<String, Integer>> create(Object... elements) {
      ImmutableSortedMap.Builder<String, Integer> builder = ImmutableSortedMap.naturalOrder();

                            .compare(
                                left.getValue(), right.getValue(), Ordering.natural().nullsFirst())
                            .result();
                      }
                    }.sortedCopy(insertionOrder);
                  }
                })
            .named("TreeMultimap nullsFirst")
            .withFeatures(
                MapFeature.ALLOWS_NULL_KEYS,

        @Override
        public int compare(Entry<String, Integer> left, Entry<String, Integer> right) {
          return left.getKey().compareTo(right.getKey());
        }
      }.sortedCopy(insertionOrder);
    }

    @Override
    public List<Entry<String, Integer>> create(Object... elements) {
      ImmutableSortedMap.Builder<String, Integer> builder = ImmutableSortedMap.naturalOrder();

                  }

                  @Override
                  public List<String> order(List<String> insertionOrder) {
                    return Ordering.natural().sortedCopy(insertionOrder);
                  }
                })
            .named("ForwardingSortedMultiset with standard impls")
            .withFeatures(
                CollectionSize.ANY,

  @SuppressWarnings("UnusedVariable") // intentionally weird Comparator
  public int compare(@Nullable Object left, @Nullable Object right) {
    return 0;
  }

  @Override
  public <E extends @Nullable Object> List<E> sortedCopy(Iterable<E> iterable) {
    return Lists.newArrayList(iterable);
  }

  @Override
  public <E> ImmutableList<E> immutableSortedCopy(Iterable<E> iterable) {
    return ImmutableList.copyOf(iterable);
  }

                  }

                  @Override
                  public List<String> order(List<String> insertionOrder) {
                    return Ordering.natural().sortedCopy(insertionOrder);
                  }
                })
            .named("ForwardingSortedMultiset with standard impls")
            .withFeatures(
                CollectionSize.ANY,

        @Override
        public int compare(Entry<AnEnum, String> left, Entry<AnEnum, String> right) {
          return left.getKey().compareTo(right.getKey());
        }
      }.sortedCopy(insertionOrder);
    }
  }

  public static class ImmutableMapValuesAsSingletonSetGenerator
      implements TestMapGenerator<String, Collection<Integer>> {

    @Override

                  public Iterable<Entry<Range<Integer>, String>> order(
                      List<Entry<Range<Integer>, String>> insertionOrder) {
                    return Range.<Integer>rangeLexOrdering().onKeys().sortedCopy(insertionOrder);
                  }

                  @SuppressWarnings("unchecked")
                  @Override
                  public Range<Integer>[] createKeyArray(int length) {

                  }

                  @Override
                  public List<String> order(List<String> insertionOrder) {
                    return Ordering.natural().sortedCopy(insertionOrder);
                  }
                })
            .withFeatures(
                CollectionSize.ANY,
                CollectionFeature.KNOWN_ORDER,
                CollectionFeature.GENERAL_PURPOSE,

      List<Integer> list = new LinkedList<>();
      for (int j = 0; j < i; j++) {
        list.add(j);
        allIntegers.add(j);
      }
      iterables.add(Ordering.<Integer>natural().sortedCopy(list));
    }

    verifyMergeSorted(iterables, allIntegers);
  }

  // Like the pyramid, but creates more unique values, along with repeated ones.
  public void testMergeSorted_skipping_pyramid() {