val response = call.execute()
    val inputStream = response.body.byteStream()
    assertThat(inputStream.read().toChar()).isEqualTo('A')
    call.cancel()
    assertFailsWith<IOException> {
      // Reading 'B' may succeed if it's buffered.
      inputStream.read()

      // But 'C' shouldn't be buffered (the response is throttled) and this should fail.
      inputStream.read()
    }
    inputStream.close()