panic("didn't get enough data")
		}
		if numSplits >= okCount {
			return 0, nil, testError
		}
		numSplits++
		return 1, data[0:1], nil
	}
	// Read the data.
	const text = "abcdefghijklmnopqrstuvwxyz"
	buf := strings.NewReader(text)
	s := NewScanner(&slowReader{1, buf})
	s.Split(errorSplit)
	var i int
	for i = 0; s.Scan(); i++ {
		if len(s.Bytes()) != 1 || text[i] != s.Bytes()[0] {

    testMarkAndReset(TransferKind.END_OF_STREAM)
  }

  private fun testMarkAndReset(transferKind: TransferKind) {
    val builder = MockResponse.Builder()
    transferKind.setBody(builder, "ABCDEFGHIJKLMNOPQRSTUVWXYZ", 1024)
    server.enqueue(builder.build())
    server.enqueue(builder.build())
    val inputStream = getResponse(newRequest("/")).body.byteStream()

		t.Fatal("ReadByte at EOF: got no error")
	}
	if err := b.UnreadByte(); err == nil {
		t.Fatal("UnreadByte after ReadByte at EOF: got no error")
	}

	// check not at EOF
	b.WriteString("abcdefghijklmnopqrstuvwxyz")

	// after unsuccessful read
	if n, err := b.Read(nil); n != 0 || err != nil {
		t.Fatalf("Read(nil) = %d,%v; want 0,nil", n, err)
	}
	if err := b.UnreadByte(); err == nil {