}

  @Test
  fun headerForbidsControlCharacters() {
    assertForbiddenHeader("\u0000")
    assertForbiddenHeader("\r")
    assertForbiddenHeader("\n")
    assertForbiddenHeader("\u001f")
    assertForbiddenHeader("\u007f")
    assertForbiddenHeader("\u0080")
    assertForbiddenHeader("\ud83c\udf69")
  }

  private fun assertForbiddenHeader(s: String) {
    val builder = Request.Builder()