@Override
        public String toString() {
          return "ByteStreams.nullOutputStream()";
        }
      };

  /**
   * Returns an {@link OutputStream} that simply discards written bytes.
   *
   * <p><b>Java 11+ users:</b> use {@link OutputStream#nullOutputStream()} instead. Note that the
   * {@link ByteStreams} method returns a singleton stream whose {@code close} method has no effect,

        NullPointerException.class, () -> ByteStreams.readFully(newTestStream(10), null, 0, 10));

    assertThrows(NullPointerException.class, () -> ByteStreams.readFully(null, b, 0, 10));

    assertThrows(
        IndexOutOfBoundsException.class, () -> ByteStreams.readFully(newTestStream(10), b, -1, 10));

    assertThrows(
        IndexOutOfBoundsException.class, () -> ByteStreams.readFully(newTestStream(10), b, 0, -1));

        NullPointerException.class, () -> ByteStreams.readFully(newTestStream(10), null, 0, 10));

    assertThrows(NullPointerException.class, () -> ByteStreams.readFully(null, b, 0, 10));

    assertThrows(
        IndexOutOfBoundsException.class, () -> ByteStreams.readFully(newTestStream(10), b, -1, 10));

    assertThrows(
        IndexOutOfBoundsException.class, () -> ByteStreams.readFully(newTestStream(10), b, 0, -1));

    Closer closer = Closer.create();
    try {
      InputStream in = closer.register(openStream());
      Optional<Long> size = sizeIfKnown();
      return size.isPresent()
          ? ByteStreams.toByteArray(in, size.get())
          : ByteStreams.toByteArray(in);
    } catch (Throwable e) {
      throw closer.rethrow(e);
    } finally {
      closer.close();
    }
  }

  /**

 */
@NullUnmarked
public class TestWriter extends FilterWriter {

  private final TestOutputStream out;

  public TestWriter(TestOption... options) throws IOException {
    this(new TestOutputStream(ByteStreams.nullOutputStream(), options));
  }

  public TestWriter(TestOutputStream out) {
    super(new OutputStreamWriter(checkNotNull(out), UTF_8));
    this.out = out;
  }

  @Override

    InputStream in = source.openStream();
    try {
      byte[] readBytes = ByteStreams.toByteArray(in);
      assertExpectedBytes(readBytes);
    } finally {
      in.close();
    }
  }

  public void testOpenBufferedStream() throws IOException {
    InputStream in = source.openBufferedStream();
    try {
      byte[] readBytes = ByteStreams.toByteArray(in);
      assertExpectedBytes(readBytes);
    } finally {

    InputStream in = source.openStream();
    try {
      byte[] readBytes = ByteStreams.toByteArray(in);
      assertExpectedBytes(readBytes);
    } finally {
      in.close();
    }
  }

  public void testOpenBufferedStream() throws IOException {
    InputStream in = source.openBufferedStream();
    try {
      byte[] readBytes = ByteStreams.toByteArray(in);
      assertExpectedBytes(readBytes);
    } finally {

 */
@NullUnmarked
public class TestWriter extends FilterWriter {

  private final TestOutputStream out;

  public TestWriter(TestOption... options) throws IOException {
    this(new TestOutputStream(ByteStreams.nullOutputStream(), options));
  }

  public TestWriter(TestOutputStream out) {
    super(new OutputStreamWriter(checkNotNull(out), UTF_8));
    this.out = out;
  }

  @Override

    InputStream in = source.openBufferedStream();
    assertTrue(source.wasStreamOpened());
    assertFalse(source.wasStreamClosed());

    ByteArrayOutputStream out = new ByteArrayOutputStream();
    ByteStreams.copy(in, out);
    in.close();
    out.close();

    assertTrue(source.wasStreamClosed());
    assertArrayEquals(bytes, out.toByteArray());
  }

  public void testSize() throws IOException {

    throw new UnsupportedOperationException("readLine is not supported");
  }

  @Override
  public void readFully(byte[] b) throws IOException {
    ByteStreams.readFully(this, b);
  }

  @Override
  public void readFully(byte[] b, int off, int len) throws IOException {
    ByteStreams.readFully(this, b, off, len);
  }

  @Override
  public int skipBytes(int n) throws IOException {
    return (int) in.skip(n);
  }