feat(pkg/trie): Add merkle proof verification support for TrieDB (#4091)

pkg/trie/triedb/node.go

@@ -52,16 +52,16 @@ func NewEncodedValue(value nodeValue, partial []byte, childF onChildStoreFn) (co
 		// Check and get new new value hash
 		switch cr := childRef.(type) {
 		case HashChildReference:
-			if cr.hash == common.EmptyHash {
+			if common.Hash(cr) == common.EmptyHash {
 				panic("new external value are always added before encoding a node")
 			}
 
 			if v.hash != common.EmptyHash {
-				if v.hash != cr.hash {
+				if v.hash != common.Hash(cr) {
 					panic("hash mismatch")
 				}
 			} else {
-				v.hash = cr.hash
+				v.hash = common.Hash(cr)
 			}
 		default:
 			panic("value node can never be inlined")
@@ -241,9 +241,9 @@ func NewChildReferences(encodedChildren [codec.ChildrenCapacity]codec.MerkleValu
 
 		switch n := child.(type) {
 		case codec.InlineNode:
-			children[i] = NewInlineChildReference(n.Data)
+			children[i] = InlineChildReference(n.Data)
 		case codec.HashedNode:
-			children[i] = NewHashChildReference(common.Hash(n.Data))
+			children[i] = HashChildReference(common.Hash(n.Data))
 		}
 	}
 	return children
@@ -256,41 +256,29 @@ type ChildReference interface {
 
 type (
 	// HashChildReference is a reference to a child node that is not inlined
-	HashChildReference struct {
-		hash common.Hash
-	}
+	HashChildReference common.Hash
 	// InlineChildReference is a reference to an inlined child node
-	InlineChildReference struct {
-		encodedNode []byte
-	}
+	InlineChildReference []byte
 )
 
 func (h HashChildReference) getNodeData() []byte {
-	return h.hash.ToBytes()
+	return h[:]
 }
 func (i InlineChildReference) getNodeData() []byte {
-	return i.encodedNode
-}
-
-func NewHashChildReference(hash common.Hash) HashChildReference {
-	return HashChildReference{hash: hash}
-}
-
-func NewInlineChildReference(encodedNode []byte) InlineChildReference {
-	return InlineChildReference{encodedNode: encodedNode}
+	return i
 }
 
 type onChildStoreFn = func(node nodeToEncode, partialKey []byte, childIndex *byte) (ChildReference, error)
 
-const emptyTrieBytes = byte(0)
+const EmptyTrieBytes = byte(0)
 
 // NewEncodedNode creates a new encoded node from a node and a child store function and return its bytes
 func NewEncodedNode(node Node, childF onChildStoreFn) (encodedNode []byte, err error) {
 	encodingBuffer := bytes.NewBuffer(nil)
 
 	switch n := node.(type) {
 	case Empty:
-		return []byte{emptyTrieBytes}, nil
+		return []byte{EmptyTrieBytes}, nil
 	case Leaf:
 		pr := n.partialKey
 		value, err := NewEncodedValue(n.value, pr, childF)