zb0001Len--
		zb0001Mask |= 0x10
	}
	// variable map header, size zb0001Len
	o = append(o, 0x80|uint8(zb0001Len))

	// skip if no fields are to be emitted
	if zb0001Len != 0 {
		// string "BaseOptions"
		o = append(o, 0xab, 0x42, 0x61, 0x73, 0x65, 0x4f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x73)
		// map header, size 0
		_ = z.BaseOptions
		o = append(o, 0x80)
		// string "r"
		o = append(o, 0xa1, 0x72)

    assertFailsWith<IllegalArgumentException> {
      Request.Builder().addHeader("a b", "c")
    }.also { expected ->
      assertThat(expected.message).isEqualTo("Unexpected char 0x20 at 1 in header name: a b")
    }
  }

  @Test
  fun requestHeaderNameWithTabForbidden() {
    assertFailsWith<IllegalArgumentException> {
      Request.Builder().addHeader("a\tb", "c")