Reuse node.EncodeAndHash inside trie.Hash

lib/trie/database.go

@@ -377,16 +377,6 @@ func (t *Trie) writeDirty(db chaindb.Batch, n Node) error {
 			n.GetHash(), err)
 	}
 
-	if n == t.root {
-		// hash root node even if its encoding is under 32 bytes
-		encodingDigest, err := common.Blake2bHash(encoding)
-		if err != nil {
-			return fmt.Errorf("cannot hash root node encoding: %w", err)
-		}
-
-		hash = encodingDigest[:]
-	}
-
 	err = db.Put(hash, encoding)
 	if err != nil {
 		return fmt.Errorf(
@@ -446,23 +436,13 @@ func (t *Trie) getInsertedNodeHashes(n Node, hashes map[common.Hash]struct{}) (e
 		return nil
 	}
 
-	encoding, hash, err := n.EncodeAndHash(n == t.root)
+	_, hash, err := n.EncodeAndHash(n == t.root)
 	if err != nil {
 		return fmt.Errorf(
 			"cannot encode and hash node with hash 0x%x: %w",
 			n.GetHash(), err)
 	}
 
-	if n == t.root && len(encoding) < 32 {
-		// hash root node even if its encoding is under 32 bytes
-		encodingDigest, err := common.Blake2bHash(encoding)
-		if err != nil {
-			return fmt.Errorf("cannot hash root node encoding: %w", err)
-		}
-
-		hash = encodingDigest[:]
-	}
-
 	hashes[common.BytesToHash(hash)] = struct{}{}
 
 	switch n.Type() {

lib/trie/trie.go

@@ -9,7 +9,6 @@ import (
 
 	"github.com/ChainSafe/gossamer/internal/trie/codec"
 	"github.com/ChainSafe/gossamer/internal/trie/node"
-	"github.com/ChainSafe/gossamer/internal/trie/pools"
 	"github.com/ChainSafe/gossamer/lib/common"
 )
 
@@ -155,16 +154,8 @@ func (t *Trie) MustHash() common.Hash {
 
 // Hash returns the hashed root of the trie.
 func (t *Trie) Hash() (rootHash common.Hash, err error) {
-	buffer := pools.EncodingBuffers.Get().(*bytes.Buffer)
-	buffer.Reset()
-	defer pools.EncodingBuffers.Put(buffer)
-
-	err = encodeRoot(t.root, buffer)
-	if err != nil {
-		return [32]byte{}, err
-	}
-
-	return common.Blake2bHash(buffer.Bytes()) // TODO optimisation: use hashers sync pools
+	_, hash, err := t.root.EncodeAndHash(true)
+	return common.BytesToHash(hash), err
 }
 
 // Entries returns all the key-value pairs in the trie as a map of keys to values