assertEquals("", joiner.join(set));
    assertEquals("", joiner.join(set.iterator()));

    Object[] array = Lists.newArrayList(set).toArray(new Integer[0]);
    assertEquals("", joiner.join(array));

    StringBuilder sb1FromIterable = new StringBuilder();
    assertSame(sb1FromIterable, joiner.appendTo(sb1FromIterable, set));
    assertEquals(0, sb1FromIterable.length());

    assertEquals(Collections.singleton(array), set);
  }

  @GwtIncompatible // ImmutableSet.chooseTableSize
  public void testChooseTableSize() {
    assertEquals(8, ImmutableSet.chooseTableSize(3));
    assertEquals(8, ImmutableSet.chooseTableSize(4));

    assertEquals(1 << 29, ImmutableSet.chooseTableSize(1 << 28));
    assertEquals(1 << 29, ImmutableSet.chooseTableSize((1 << 29) * 3 / 5));

    Set<String> all = Sets.union(friends, enemies);
    assertEquals(5, all.size());

    ImmutableSet<String> immut = Sets.union(friends, enemies).immutableCopy();
    HashSet<String> mut = Sets.union(friends, enemies).copyInto(new HashSet<String>());

    enemies.add("Buck");
    assertEquals(6, all.size());
    assertEquals(5, immut.size());
    assertEquals(5, mut.size());
  }

  public void testIntersection() {

    assertEquals(Ordering.natural(), asMap.comparator());
    assertEquals("foo", asMap.firstKey());
    assertEquals("tree", asMap.lastKey());
    Set<Integer> fooValues = ImmutableSet.of(1, 3, 7);
    Set<Integer> googleValues = ImmutableSet.of(2, 6);
    Set<Integer> treeValues = ImmutableSet.of(4, 0);

    // the underlying supplier hasn't executed yet
    assertEquals(0, countingSupplier.calls);

    assertEquals(10, (int) memoizedSupplier.get());

    // now it has
    assertEquals(1, countingSupplier.calls);

    assertEquals(10, (int) memoizedSupplier.get());

    // it still should only have executed once due to memoization
    assertEquals(1, countingSupplier.calls);
  }

  public void testMemoize() {

    // the underlying supplier hasn't executed yet
    assertEquals(0, countingSupplier.calls);

    assertEquals(10, (int) memoizedSupplier.get());

    // now it has
    assertEquals(1, countingSupplier.calls);

    assertEquals(10, (int) memoizedSupplier.get());

    // it still should only have executed once due to memoization
    assertEquals(1, countingSupplier.calls);
  }

  public void testMemoize() {

        assertEquals(mutable, copy);
      }

      ImmutableRangeSet<Integer> built = builder.build();
      assertEquals(mutable, built);
      assertEquals(ImmutableRangeSet.copyOf(mutable), built);
      assertEquals(mutable.complement(), built.complement());

      for (int i = 0; i <= 11; i++) {
        assertEquals(mutable.contains(i), built.contains(i));
      }

    assertMapsEqual(expected, map);
    assertEquals(expected.get("a"), map.get("a"));
    assertEquals(expected.containsKey("a"), map.containsKey("a"));
    assertEquals(expected.get("b"), map.get("b"));
    assertEquals(expected.containsKey("b"), map.containsKey("b"));
    assertEquals(expected.get("c"), map.get("c"));
    assertEquals(expected.containsKey("c"), map.containsKey("c"));
  }

    assertTrue(bimap.isEmpty());
    assertEquals("{}", bimap.toString());
    assertEquals(HashBiMap.create(), bimap);
    bimap.put(Currency.DOLLAR, Country.CANADA);
    assertEquals(Country.CANADA, bimap.get(Currency.DOLLAR));
    assertEquals(Currency.DOLLAR, bimap.inverse().get(Country.CANADA));
  }

  public void testCreateFromMap() {

    assertTrue(bimap.isEmpty());
    assertEquals("{}", bimap.toString());
    assertEquals(HashBiMap.create(), bimap);
    bimap.put(Currency.DOLLAR, Country.CANADA);
    assertEquals(Country.CANADA, bimap.get(Currency.DOLLAR));
    assertEquals(Currency.DOLLAR, bimap.inverse().get(Country.CANADA));
  }

  public void testCreateFromMap() {