assertEqualCharNodes(traverser.breadthFirst(charactersOf("")), "");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("bc")), "bcd");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("a")), "abcd");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("acdb")), "acdb");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("db")), "db");
  }

  @Test

    assertEqualCharNodes(traverser.breadthFirst(charactersOf("")), "");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("bc")), "bcd");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("a")), "abcd");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("acdb")), "acdb");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("db")), "db");
  }

  @Test

    @Override
    public List<Character> create(Character[] elements) {
      char[] chars = Chars.toArray(Arrays.asList(elements));
      return Lists.charactersOf(String.copyValueOf(chars));
    }
  }

  public static class CharactersOfCharSequenceGenerator extends TestCharacterListGenerator {
    @Override
    public List<Character> create(Character[] elements) {

    SpliteratorTester.of(
            () ->
                CollectSpliterators.flatMap(
                    Arrays.spliterator(new String[] {"abc", "", "de", "f", "g", ""}),
                    (String str) -> Lists.charactersOf(str).spliterator(),
                    Spliterator.SIZED | Spliterator.DISTINCT | Spliterator.NONNULL,
                    7))
        .expect('a', 'b', 'c', 'd', 'e', 'f', 'g');
  }

    @Override
    public List<Character> create(Character[] elements) {
      char[] chars = Chars.toArray(Arrays.asList(elements));
      return Lists.charactersOf(String.copyValueOf(chars));
    }
  }

  public static class CharactersOfCharSequenceGenerator extends TestCharacterListGenerator {
    @Override
    public List<Character> create(Character[] elements) {

            .named("Lists.charactersOf[CharSequence]")
            .withFeatures(CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_QUERIES)
            .createTestSuite());

    return suite;
  }

  public void testCharactersOfIsView() {
    StringBuilder builder = new StringBuilder("abc");
    List<Character> chars = Lists.charactersOf(builder);
    assertEquals(asList('a', 'b', 'c'), chars);

            .named("Lists.charactersOf[CharSequence]")
            .withFeatures(CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_QUERIES)
            .createTestSuite());

    return suite;
  }

  public void testCharactersOfIsView() {
    StringBuilder builder = new StringBuilder("abc");
    List<Character> chars = Lists.charactersOf(builder);
    assertEquals(asList('a', 'b', 'c'), chars);

   *
   * @param sequence the character sequence to view as a {@code List} of characters
   * @return an {@code List<Character>} view of the character sequence
   * @since 7.0
   */
  public static List<Character> charactersOf(CharSequence sequence) {
    return new CharSequenceAsList(checkNotNull(sequence));
  }

   0080-009F; [CONTROL CHARACTERS]
   06DD; ARABIC END OF AYAH
   070F; SYRIAC ABBREVIATION MARK
   180E; MONGOLIAN VOWEL SEPARATOR
   200C; ZERO WIDTH NON-JOINER
   200D; ZERO WIDTH JOINER
   2028; LINE SEPARATOR
   2029; PARAGRAPH SEPARATOR
   2060; WORD JOINER
   2061; FUNCTION APPLICATION
   2062; INVISIBLE TIMES
   2063; INVISIBLE SEPARATOR
   206A-206F; [CONTROL CHARACTERS]
   FEFF; ZERO WIDTH NO-BREAK SPACE

    }

    /**
     * Sets the replacement string for any characters outside the 'safe' range that have no explicit
     * replacement. If {@code unsafeReplacement} is {@code null} then no replacement will occur, if
     * it is {@code ""} then the unsafe characters are removed from the output.
     *
     * @param unsafeReplacement the string to replace unsafe characters
     * @return the builder instance
     */