}
	if readHash.Sum32() != wroteHash.Sum32() {
		t.Fatalf("expect read hash 0x%08x but got 0x%08x", readHash.Sum32(), wroteHash.Sum32())
	}
}

func TestRingBuffer_ByteInterface(t *testing.T) {
	defer timeout(5 * time.Second)()
	rb := New(2)

	// write one
	err := rb.WriteByte('a')
	if err != nil {
		t.Fatalf("WriteByte failed: %v", err)
	}
	if rb.Length() != 1 {