From bee1fac1301dcc222eb8e1a0e79010e680274752 Mon Sep 17 00:00:00 2001
From: Quentin McGaw <quentin.mcgaw@gmail.com>
Date: Fri, 12 Nov 2021 13:19:53 +0000
Subject: [PATCH] Do not copy when not needed

---
 lib/trie/node.go | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/lib/trie/node.go b/lib/trie/node.go
index 8fcaa0c715..efe88c2df9 100644
--- a/lib/trie/node.go
+++ b/lib/trie/node.go
@@ -243,13 +243,13 @@ func (b *branch) encodeAndHash() (encoding, hash []byte, err error) {
 	b.encoding = make([]byte, len(bufferBytes))
 	encoding = make([]byte, len(bufferBytes))
 	copy(b.encoding, bufferBytes)
-	copy(encoding, bufferBytes)
+	encoding = b.encoding // no need to copy
 
 	if buffer.Len() < 32 {
 		b.hash = make([]byte, len(bufferBytes))
 		hash = make([]byte, len(bufferBytes))
 		copy(b.hash, bufferBytes)
-		copy(hash, bufferBytes)
+		hash = b.hash // no need to copy
 		return encoding, hash, nil
 	}
 
@@ -259,7 +259,7 @@ func (b *branch) encodeAndHash() (encoding, hash []byte, err error) {
 		return nil, nil, err
 	}
 	b.hash = hashArray[:]
-	hash = hashArray[:]
+	hash = b.hash // no need to copy
 
 	return encoding, hash, nil
 }
@@ -281,15 +281,13 @@ func (l *leaf) encodeAndHash() (encoding, hash []byte, err error) {
 	bufferBytes := buffer.Bytes()
 
 	l.encoding = make([]byte, len(bufferBytes))
-	encoding = make([]byte, len(bufferBytes))
 	copy(l.encoding, bufferBytes)
-	copy(encoding, bufferBytes)
+	encoding = l.encoding // no need to copy
 
 	if len(bufferBytes) < 32 {
 		l.hash = make([]byte, len(bufferBytes))
-		hash = make([]byte, len(bufferBytes))
 		copy(l.hash, bufferBytes)
-		copy(hash, bufferBytes)
+		hash = l.hash
 		return encoding, hash, nil
 	}
 
@@ -300,7 +298,7 @@ func (l *leaf) encodeAndHash() (encoding, hash []byte, err error) {
 	}
 
 	l.hash = hashArray[:]
-	hash = hashArray[:]
+	hash = l.hash // no need to copy
 
 	return encoding, hash, nil
 }