assertThat(Longs.join(",", (long) 1, (long) 2)).isEqualTo("1,2");
    assertThat(Longs.join("", (long) 1, (long) 2, (long) 3)).isEqualTo("123");
  }

  public void testLexicographicalComparator() {
    List<long[]> ordered =
        Arrays.asList(
            new long[] {},
            new long[] {MIN_VALUE},
            new long[] {MIN_VALUE, MIN_VALUE},
            new long[] {MIN_VALUE, (long) 1},
            new long[] {(long) 1},

    assertThat(Doubles.join(",", 1.3, 2.4)).isEqualTo("1.3,2.4");
    assertThat(Doubles.join("", 1.4, 2.5, 3.6)).isEqualTo("1.42.53.6");
  }

  public void testLexicographicalComparator() {
    List<double[]> ordered =
        Arrays.asList(
            new double[] {},
            new double[] {LEAST},
            new double[] {LEAST, LEAST},
            new double[] {LEAST, (double) 1},
            new double[] {(double) 1},

    assertThat(Longs.join(",", (long) 1, (long) 2)).isEqualTo("1,2");
    assertThat(Longs.join("", (long) 1, (long) 2, (long) 3)).isEqualTo("123");
  }

  public void testLexicographicalComparator() {
    List<long[]> ordered =
        Arrays.asList(
            new long[] {},
            new long[] {MIN_VALUE},
            new long[] {MIN_VALUE, MIN_VALUE},
            new long[] {MIN_VALUE, (long) 1},
            new long[] {(long) 1},

            new RegularImmutableList<V>(values));
    }
  }

  /**
   * Returns a builder that creates immutable sorted maps whose keys are ordered by their natural
   * ordering. The sorted maps use {@link Ordering#natural()} as the comparator.
   */
  public static <K extends Comparable<?>, V> Builder<K, V> naturalOrder() {
    return new Builder<>(Ordering.natural());

 * @author George van den Driessche
 */
// TODO: Descriptive assertion messages, with hints as to probable fixes.
// TODO: Add another constructor parameter indicating whether the class under test is ordered, and
// check the order if so.
// TODO: Refactor to share code with SetTestBuilder etc.
@GwtCompatible
@ElementTypesAreNonnullByDefault

    /**
     * A queue of elements currently in the map, ordered by write time. Elements are added to the
     * tail of the queue on write.
     */
    @GuardedBy("this")
    final Queue<ReferenceEntry<K, V>> writeQueue;

    /**
     * A queue of elements currently in the map, ordered by access time. Elements are added to the

    EndpointPair<String> ordered = EndpointPair.ordered("source", "target");
    assertThat(ordered.isOrdered()).isTrue();
    assertThat(ordered).containsExactly("source", "target").inOrder();
    assertThat(ordered.source()).isEqualTo("source");
    assertThat(ordered.target()).isEqualTo("target");
    assertThat(ordered.nodeU()).isEqualTo("source");
    assertThat(ordered.nodeV()).isEqualTo("target");

    EndpointPair<String> ordered = EndpointPair.ordered("source", "target");
    assertThat(ordered.isOrdered()).isTrue();
    assertThat(ordered).containsExactly("source", "target").inOrder();
    assertThat(ordered.source()).isEqualTo("source");
    assertThat(ordered.target()).isEqualTo("target");
    assertThat(ordered.nodeU()).isEqualTo("source");
    assertThat(ordered.nodeV()).isEqualTo("target");

    populateStarShapedGraph();

    assertThat(graph.edges())
        .containsExactly(
            EndpointPair.ordered(2, 1),
            EndpointPair.ordered(1, 4),
            EndpointPair.ordered(1, 3),
            EndpointPair.ordered(1, 2),
            EndpointPair.ordered(3, 1),
            EndpointPair.ordered(5, 1))
        .inOrder();
  }

  @Test

    iter.remove();

    // forward map ordered by currency
    assertThat(bimap.keySet()).containsExactly(Currency.FRANC, Currency.PESO).inOrder();
    // forward map ordered by currency (even for country values)
    assertThat(bimap.values()).containsExactly(Country.SWITZERLAND, Country.CHILE).inOrder();
    // backward map ordered by country
    assertThat(bimap.inverse().keySet())