const val FLAG_ACK = 0x1 // Used for settings and ping.
  const val FLAG_END_STREAM = 0x1 // Used for headers and data.
  const val FLAG_END_HEADERS = 0x4 // Used for headers and continuation.
  const val FLAG_END_PUSH_PROMISE = 0x4
  const val FLAG_PADDED = 0x8 // Used for headers and data.
  const val FLAG_PRIORITY = 0x20 // Used for headers.
  const val FLAG_COMPRESSED = 0x20 // Used for data.

  /** Lookup table for valid frame types. */

      .isEqualTo("<< 0x00000003 10000 CONTINUATION  END_HEADERS")
    assertThat(frameLog(true, 4, 10000, TYPE_PUSH_PROMISE, 0x4))
      .isEqualTo("<< 0x00000004 10000 PUSH_PROMISE  END_PUSH_PROMISE")
  }

  @Test
  fun flagOverlapOn0x20() {
    assertThat(frameLog(true, 3, 10000, TYPE_HEADERS, 0x20))
      .isEqualTo("<< 0x00000003 10000 HEADERS       PRIORITY")

    val headerBytes = literalHeaders(pushPromise)
    writeMedium(frame, (headerBytes.size + 4).toInt())
    frame.writeByte(Http2.TYPE_PUSH_PROMISE)
    frame.writeByte(Http2.FLAG_END_PUSH_PROMISE)
    frame.writeInt(expectedStreamId and 0x7fffffff)
    frame.writeInt(expectedPromisedStreamId and 0x7fffffff)
    frame.writeAll(headerBytes)