fix more compile issues

frontend/service.go

@@ -374,7 +374,7 @@ func (s *lwdStreamer) GetMempoolStream(_empty *walletrpc.Empty, resp walletrpc.C
 var mempoolMap *map[string]*walletrpc.CompactTx
 var mempoolList []string
 
-// Last time we pulled a copy of the mempool from zcashd.
+// Last time we pulled a copy of the mempool from hushd
 var lastMempool time.Time
 
 func (s *lwdStreamer) GetMempoolTx(exclude *walletrpc.Exclude, resp walletrpc.CompactTxStreamer_GetMempoolTxServer) error {
@@ -419,7 +419,7 @@ func (s *lwdStreamer) GetMempoolTx(exclude *walletrpc.Exclude, resp walletrpc.Co
 				return err
 			}
 
-			// conver to binary
+			// convert to binary
 			txBytes, err := hex.DecodeString(txStr)
 			if err != nil {
 				return err

parser/block.go

@@ -1,3 +1,7 @@
+// Copyright (c) 2019-2022 The Hush developers
+// Copyright (c) 2019-2020 The Zcash developers
+
+// Package parser deserializes blocks from hushd
 package parser
 
 import (

parser/transaction.go

@@ -126,6 +126,13 @@ func (p *spend) ParseFromSlice(data []byte) ([]byte, error) {
 	return []byte(s), nil
 }
 
+// HasSaplingElements indicates whether a transaction has
+// at least one sapling shielded input or output.
+func (tx *Transaction) HasSaplingElements() bool {
+	nshielded := len(tx.shieldedSpends) + len(tx.shieldedOutputs)
+	return tx.version >= 4 && nshielded > 0
+}
+
 func (p *spend) ToCompact() *walletrpc.CompactSpend {
 	return &walletrpc.CompactSpend{
 		Nf: p.nullifier,