trie: replace custom logic with bytes.HasPrefix (#30771)

in `trie`
- Replace custom logic with `bytes.HasPrefix`
- Remove unnecessary code in `GetNode`

trie/proof.go

@@ -48,7 +48,7 @@ func (t *Trie) Prove(key []byte, proofDb ethdb.KeyValueWriter) error {
 	for len(key) > 0 && tn != nil {
 		switch n := tn.(type) {
 		case *shortNode:
-			if len(key) < len(n.Key) || !bytes.Equal(n.Key, key[:len(n.Key)]) {
+			if !bytes.HasPrefix(key, n.Key) {
 				// The trie doesn't contain the key.
 				tn = nil
 			} else {
@@ -371,7 +371,7 @@ func unset(parent node, child node, key []byte, pos int, removeLeft bool) error
 		}
 		return unset(cld, cld.Children[key[pos]], key, pos+1, removeLeft)
 	case *shortNode:
-		if len(key[pos:]) < len(cld.Key) || !bytes.Equal(cld.Key, key[pos:pos+len(cld.Key)]) {
+		if !bytes.HasPrefix(key[pos:], cld.Key) {
 			// Find the fork point, it's a non-existent branch.
 			if removeLeft {
 				if bytes.Compare(cld.Key, key[pos:]) < 0 {
@@ -434,7 +434,7 @@ func hasRightElement(node node, key []byte) bool {
 			}
 			node, pos = rn.Children[key[pos]], pos+1
 		case *shortNode:
-			if len(key)-pos < len(rn.Key) || !bytes.Equal(rn.Key, key[pos:pos+len(rn.Key)]) {
+			if !bytes.HasPrefix(key[pos:], rn.Key) {
 				return bytes.Compare(rn.Key, key[pos:]) > 0
 			}
 			node, pos = rn.Val, pos+len(rn.Key)
@@ -589,7 +589,7 @@ func get(tn node, key []byte, skipResolved bool) ([]byte, node) {
 	for {
 		switch n := tn.(type) {
 		case *shortNode:
-			if len(key) < len(n.Key) || !bytes.Equal(n.Key, key[:len(n.Key)]) {
+			if !bytes.HasPrefix(key, n.Key) {
 				return nil, nil
 			}
 			tn = n.Val

trie/trie.go

@@ -163,7 +163,7 @@ func (t *Trie) get(origNode node, key []byte, pos int) (value []byte, newnode no
 	case valueNode:
 		return n, n, false, nil
 	case *shortNode:
-		if len(key)-pos < len(n.Key) || !bytes.Equal(n.Key, key[pos:pos+len(n.Key)]) {
+		if !bytes.HasPrefix(key[pos:], n.Key) {
 			// key not found in trie
 			return nil, n, false, nil
 		}
@@ -219,9 +219,6 @@ func (t *Trie) GetNode(path []byte) ([]byte, int, error) {
 	if resolved > 0 {
 		t.root = newroot
 	}
-	if item == nil {
-		return nil, resolved, nil
-	}
 	return item, resolved, nil
 }
 
@@ -254,7 +251,7 @@ func (t *Trie) getNode(origNode node, path []byte, pos int) (item []byte, newnod
 		return nil, nil, 0, nil
 
 	case *shortNode:
-		if len(path)-pos < len(n.Key) || !bytes.Equal(n.Key, path[pos:pos+len(n.Key)]) {
+		if !bytes.HasPrefix(path[pos:], n.Key) {
 			// Path branches off from short node
 			return nil, n, 0, nil
 		}