}

    assertTrue(source.wasStreamClosed());
    assertEquals(SPLIT_LINES, lines);
  }

  public void testCopyTo_appendable() throws IOException {
    StringBuilder builder = new StringBuilder();

    assertEquals(STRING.length(), source.copyTo(builder));
    assertTrue(source.wasStreamOpened() && source.wasStreamClosed());

    assertEquals(STRING, builder.toString());
  }

    @Override
    public List<Character> create(Character[] elements) {
      char[] chars = Chars.toArray(asList(elements));
      StringBuilder str = new StringBuilder();
      str.append(chars);
      return charactersOf(str);
    }
  }

  private abstract static class TestUnhashableListGenerator

    @Override
    public List<Character> create(Character[] elements) {
      char[] chars = Chars.toArray(asList(elements));
      StringBuilder str = new StringBuilder();
      str.append(chars);
      return charactersOf(str);
    }
  }

  private abstract static class TestUnhashableListGenerator

   *
   * <p>To create a {@code HashCode} from its string representation, see {@link #fromString}.
   */
  @Override
  public final String toString() {
    byte[] bytes = getBytesInternal();
    StringBuilder sb = new StringBuilder(2 * bytes.length);
    for (byte b : bytes) {
      sb.append(hexDigits[(b >> 4) & 0xf]).append(hexDigits[b & 0xf]);
    }
    return sb.toString();
  }

   *
   * <p>To create a {@code HashCode} from its string representation, see {@link #fromString}.
   */
  @Override
  public final String toString() {
    byte[] bytes = getBytesInternal();
    StringBuilder sb = new StringBuilder(2 * bytes.length);
    for (byte b : bytes) {
      sb.append(hexDigits[(b >> 4) & 0xf]).append(hexDigits[b & 0xf]);
    }
    return sb.toString();
  }

    checkNotNull(separator);
    if (array.length == 0) {
      return "";
    }

    // For pre-sizing a builder, just get the right order of magnitude
    StringBuilder builder = new StringBuilder(array.length * 5);
    builder.append(toString(array[0]));
    for (int i = 1; i < array.length; i++) {
      builder.append(separator).append(toString(array[i]));
    }
    return builder.toString();

    checkNotNull(separator);
    if (array.length == 0) {
      return "";
    }

    // For pre-sizing a builder, just get the right order of magnitude
    StringBuilder builder = new StringBuilder(array.length * 5);
    builder.append(toString(array[0]));
    for (int i = 1; i < array.length; i++) {
      builder.append(separator).append(toString(array[i]));
    }
    return builder.toString();

   * The iterator will be left exhausted: its {@code hasNext()} method will return {@code false}.
   */
  public static String toString(Iterator<?> iterator) {
    StringBuilder sb = new StringBuilder().append('[');
    boolean first = true;
    while (iterator.hasNext()) {
      if (!first) {
        sb.append(", ");
      }
      first = false;
      sb.append(iterator.next());
    }

            .withFeatures(CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_QUERIES)
            .createTestSuite());

    return suite;
  }

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

            .withFeatures(CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_QUERIES)
            .createTestSuite());

    return suite;
  }

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