assertFailsWith<ProtocolException> {
      clientReader.processNextFrame()
    }.also { expected ->
      assertThat(expected.message).isEqualTo("Unexpected rsv3 flag")
    }
  }

  @Test fun clientSentFramesMustBeMasked() {
    data.write("8100".decodeHex())
    assertFailsWith<ProtocolException> {
      serverReader.processNextFrame()
    }.also { expected ->
      assertThat(expected.message)