}
	s.db = &cacheDB{
		updatedNodes: byteCache{cache: updateCache},
	}
	s.loadDefaultHashes()
	return s
}

func (s *smt) Root() []byte {
	s.rootMu.RLock()
	defer s.rootMu.RUnlock()
	return s.root
}

// loadDefaultHashes creates the default hashes
func (s *smt) loadDefaultHashes() {
	s.defaultHashes = make([][]byte, s.trieHeight+1)
	s.defaultHashes[0] = defaultLeaf
	var h []byte

	keys := getFreshData(10)
	values := getFreshData(10)
	_, err := smt.Update(keys, values)
	assert.NoError(t, err)
	smt.db.updatedNodes = byteCache{cache: cache.NewTTL(forever, time.Minute)}
	smt.loadDefaultHashes()

	// Check errors are raised is a keys is not in cache nor db
	for _, key := range keys {
		_, err := smt.Get(key)
		assert.Error(t, err)