fail();
    } catch (NullPointerException ok) {
    }
  }

  public void testAsOutputStream() throws Exception {
    PrimitiveSink sink = mock(PrimitiveSink.class);
    OutputStream out = Funnels.asOutputStream(sink);
    byte[] bytes = {1, 2, 3, 4};
    out.write(255);
    out.write(bytes);
    out.write(bytes, 1, 2);
    verify(sink).putByte((byte) 255);
    verify(sink).putBytes(bytes);

   * @throws IOException if an I/O error occurs while reading from this source
   */
  public HashCode hash(HashFunction hashFunction) throws IOException {
    Hasher hasher = hashFunction.newHasher();
    copyTo(Funnels.asOutputStream(hasher));
    return hasher.hash();
  }

  /**
   * Checks that the contents of this byte source are equal to the contents of the given byte
   * source.
   *