}
  }

  @Test fun addThrowsOnMultiColon() {
    assertFailsWith<IllegalArgumentException> {
      Headers.Builder().add(":status: 200 OK")
    }
  }

  @Test fun addUnsafeNonAsciiRejectsUnicodeName() {
    assertFailsWith<IllegalArgumentException> {
      Headers.Builder()
        .addUnsafeNonAscii("héader1", "value1")
        .build()
    }.also { expected ->