assertEquals(Ordering.natural(), copyFromHash.valueComparator());
  }

  /** Test that creating one TreeMultimap from a SortedSetMultimap uses natural ordering. */
  public void testCreateFromSortedSetMultimap() {
    SortedSetMultimap<Double, Double> tree = TreeMultimap.create(KEY_COMPARATOR, VALUE_COMPARATOR);
    tree.put(1.0, 2.0);
    tree.put(2.0, 3.0);
    tree.put(3.0, 4.0);
    tree.put(4.0, 5.0);