fun assertPing(payload: ByteString) {
    assertThat(nextEvent()).isEqualTo(Ping(payload))
  }

  fun assertPong(payload: ByteString) {
    assertThat(nextEvent()).isEqualTo(Pong(payload))
  }

  fun assertClosing(
    code: Int,
    reason: String,
  ) {
    assertThat(nextEvent()).isEqualTo(Closing(code, reason))
  }

  fun assertClosed(
    code: Int,
    reason: String,
  ) {