testStreamingEncodingWithSeparators(enc, "foob", "Zm9vYg");
    testStreamingEncodingWithSeparators(enc, "fooba", "Zm9vYmE");
    testStreamingEncodingWithSeparators(enc, "foobar", "Zm9vYmFy");
  }

  public void testBase64Offset() {
    testEncodesWithOffset(base64(), "foobar", 0, 6, "Zm9vYmFy");
    testEncodesWithOffset(base64(), "foobar", 1, 5, "b29iYXI=");
    testEncodesWithOffset(base64(), "foobar", 2, 3, "b2Jh");