assertTrue(set.isEmpty());
    set.add(new DerivedComparable("foo"), 2);
    set.add(new DerivedComparable("bar"), 3);
    assertThat(set)
        .containsExactly(
            new DerivedComparable("bar"),
            new DerivedComparable("bar"),
            new DerivedComparable("bar"),
            new DerivedComparable("foo"),
            new DerivedComparable("foo"))
        .inOrder();
  }

    @Override
    public SampleElements<Entry<String, Integer>> samples() {
      return new SampleElements<>(
          Maps.immutableEntry("bar", 1),
          Maps.immutableEntry("bar", 2),
          Maps.immutableEntry("foo", 3),
          Maps.immutableEntry("bar", 3),
          Maps.immutableEntry("cat", 2));
    }

    @Override
    public Collection<Entry<String, Integer>> create(Object... elements) {

    multimap.put(new DerivedComparable("bar"), new DerivedComparable("b"));
    multimap.put(new DerivedComparable("bar"), new DerivedComparable("a"));
    multimap.put(new DerivedComparable("bar"), new DerivedComparable("r"));
    assertThat(multimap.keySet())
        .containsExactly(new DerivedComparable("bar"), new DerivedComparable("foo"))
        .inOrder();
    assertThat(multimap.values())

        return Lists.asList("foo", new String[] {"bar", "baz"}).iterator();
      }
    }.test();
  }

  private void checkFooBarBazList(List<String> list) {
    assertThat(list).containsExactly("foo", "bar", "baz").inOrder();
    assertEquals(3, list.size());
    assertIndexIsOutOfBounds(list, -1);
    assertEquals("foo", list.get(0));
    assertEquals("bar", list.get(1));
    assertEquals("baz", list.get(2));

          "",
          " ",
          "127.0.0.1",
          "::1",
          "13",
          "abc.12c",
          "foo-.com",
          "_bar.quux",
          "foo+bar.com",
          "foo!bar.com",
          ".foo.com",
          "..bar.com",
          "baz..com",
          "..quiffle.com",
          "fleeb.com..",
          ".",
          "..",
          "...",

    Predicate<CharSequence> isFoobar = Predicates.containsPattern("^Fo.*o.*bar$");
    assertTrue(isFoobar.apply("Foxyzoabcbar"));
    assertFalse(isFoobar.apply("Foobarx"));
  }

  @GwtIncompatible // Predicates.containsPattern
  public void testContains_apply() {
    Predicate<CharSequence> isFoobar = Predicates.contains(Pattern.compile("^Fo.*o.*bar$"));

    assertTrue(isFoobar.apply("Foxyzoabcbar"));

    multimap.put(new DerivedComparable("bar"), new DerivedComparable("b"));
    multimap.put(new DerivedComparable("bar"), new DerivedComparable("a"));
    multimap.put(new DerivedComparable("bar"), new DerivedComparable("r"));
    assertThat(multimap.keySet())
        .containsExactly(new DerivedComparable("bar"), new DerivedComparable("foo"))
        .inOrder();
    assertThat(multimap.values())

    multiset.add("foo", 2);
    multiset.add("bar");
    assertEquals(3, multiset.size());
    assertEquals(2, multiset.count("foo"));
    assertEquals("[foo x 2, bar]", multiset.toString());
  }

  public void testCreateFromIterable() {
    Multiset<String> multiset = TreeMultiset.create(Arrays.asList("foo", "bar", "foo"));
    assertEquals(3, multiset.size());
    assertEquals(2, multiset.count("foo"));

  public void testDontConvertCharSequenceToString() {
    assertEquals("foo,foo", Joiner.on(",").join(new DontStringMeBro(), new DontStringMeBro()));
    assertEquals(
        "foo,bar,foo",
        Joiner.on(",").useForNull("bar").join(new DontStringMeBro(), null, new DontStringMeBro()));
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNullPointers() {

  public void testControlsArraySize() {
    ImmutableSet.Builder<String> builder = new ImmutableSet.Builder<String>();
    for (int i = 0; i < 10; i++) {
      builder.add("foo");
    }
    builder.add("bar");
    RegularImmutableSet<String> set = (RegularImmutableSet<String>) builder.build();
    assertTrue(set.elements.length <= 2 * set.size());
  }

  @GwtIncompatible("internals")
  public void testReusedBuilder() {