+ "field1=This is string., field2=[abc, def, ghi], field3={abc=1, def=2, ghi=3}}";

    assertEquals(expected, toTest);
  }

  public void testToStringLenient_complexFields() {
    Map<String, Integer> map =
        ImmutableMap.<String, Integer>builder().put("abc", 1).put("def", 2).put("ghi", 3).build();
    String toTest =
        MoreObjects.toStringHelper(new TestClass())
            .add("field1", "This is string.")

    assertEquals(java.util.Optional.of("abc"), Optional.toJavaUtil(Optional.of("abc")));
  }

  public void testToJavaUtil_instance() {
    assertEquals(java.util.Optional.empty(), Optional.absent().toJavaUtil());
    assertEquals(java.util.Optional.of("abc"), Optional.of("abc").toJavaUtil());
  }

  public void testFromJavaUtil() {
    assertNull(Optional.fromJavaUtil(null));

    assertEqualCharNodes(traverser.depthFirstPreOrder(charactersOf("bc")), "bdc");
    assertEqualCharNodes(traverser.depthFirstPreOrder(charactersOf("a")), "abdc");
    assertEqualCharNodes(traverser.depthFirstPreOrder(charactersOf("acdb")), "abdc");
    assertEqualCharNodes(traverser.depthFirstPreOrder(charactersOf("db")), "db");
  }

  @Test
  public void forGraph_depthFirstPreOrder_multigraph() {

    assertFailsToDecode(base32(), "let's not talk of love or chains!");
    // An 8n+{1,3,6} length string is never legal base32.
    assertFailsToDecode(base32(), "A", "Invalid input length 1");
    assertFailsToDecode(base32(), "ABC");
    assertFailsToDecode(base32(), "ABCDEF");
    // These have a combination of invalid length, unrecognized characters and wrong padding.
    assertFailsToDecode(base32(), "AB=C", "Unrecognized character: =");

  public void testReadEmptyString() throws IOException {
    assertReadsCorrectly("");
  }

  public void testReadsStringsCorrectly() throws IOException {
    assertReadsCorrectly("abc");
    assertReadsCorrectly("abcde");
    assertReadsCorrectly("abcdefghijkl");
    assertReadsCorrectly(
        ""
            + "abcdefghijklmnopqrstuvwxyz\n"
            + "ABCDEFGHIJKLMNOPQRSTUVWXYZ\r"

  }

  @SuppressWarnings("unchecked") // functor classes have no type parameters
  public void testGet_functors() {
    assertEquals(0, ArbitraryInstances.get(Comparator.class).compare("abc", 123));
    assertTrue(ArbitraryInstances.get(Predicate.class).apply("abc"));
    assertTrue(ArbitraryInstances.get(Equivalence.class).equivalent(1, 1));
    assertFalse(ArbitraryInstances.get(Equivalence.class).equivalent(1, 2));
  }

  private static final ImmutableSet<String> VALID_NAME =
      ImmutableSet.of(
          "foo.com",
          "f-_-o.cOM",
          "f--1.com",
          "f11-1.com",
          "www",
          "abc.a23",
          "biz.com.ua",
          "x",
          "fOo",
          "f--o",
          "f_a",
          "foo.net.us\uFF61ocm",
          "woo.com.",
          "8server.shop",
          "123.cn",

                unfiltered.add("yyy");
                unfiltered.addAll(ImmutableList.copyOf(elements));
                unfiltered.add("zzz");
                unfiltered.add("abc");
                return Sets.filter(
                    Sets.filter(unfiltered, Collections2Test.LENGTH_1),
                    Collections2Test.NOT_YYY_ZZZ);
              }
            })

      String.valueOf(Character.MIN_LOW_SURROGATE),
      Character.MIN_LOW_SURROGATE + "xyz",
      "abc" + Character.MIN_LOW_SURROGATE,
      "abc" + Character.MIN_LOW_SURROGATE + "xyz",
      String.valueOf(Character.MAX_LOW_SURROGATE),
      Character.MAX_LOW_SURROGATE + "xyz",
      "abc" + Character.MAX_LOW_SURROGATE,
      "abc" + Character.MAX_LOW_SURROGATE + "xyz",
    };
    for (String s : BAD_STRINGS) {
      try {

            + "field1=This is string., field2=[abc, def, ghi], field3={abc=1, def=2, ghi=3}}";

    assertEquals(expected, toTest);
  }

  public void testToStringLenient_complexFields() {
    Map<String, Integer> map =
        ImmutableMap.<String, Integer>builder().put("abc", 1).put("def", 2).put("ghi", 3).build();
    String toTest =
        MoreObjects.toStringHelper(new TestClass())
            .add("field1", "This is string.")