Transaction: initialize to ZERO earlier

src/transaction.js

@@ -306,8 +306,6 @@ Transaction.prototype.hashForSignature = function (inIndex, prevOutScript, hashT
 Transaction.prototype.hashForWitnessV0 = function (inIndex, prevOutScript, amount, hashType) {
   typeforce(types.tuple(types.UInt32, types.Buffer, types.Satoshi, types.UInt32), arguments)
 
-  var hashOutputs, hashPrevouts, hashSequence
-
   var tbuffer, toffset
   function writeSlice (slice) { toffset += slice.copy(tbuffer, toffset) }
   function writeUInt32 (i) { toffset = tbuffer.writeUInt32LE(i, toffset) }
@@ -315,6 +313,10 @@ Transaction.prototype.hashForWitnessV0 = function (inIndex, prevOutScript, amoun
   function writeVarInt (i) { toffset += bufferutils.writeVarInt(tbuffer, i, toffset) }
   function writeVarSlice (slice) { writeVarInt(slice.length); writeSlice(slice) }
 
+  var hashOutputs = ZERO
+  var hashPrevouts = ZERO
+  var hashSequence = ZERO
+
   if (!(hashType & Transaction.SIGHASH_ANYONECANPAY)) {
     tbuffer = new Buffer(36 * this.ins.length)
     toffset = 0
@@ -366,10 +368,6 @@ Transaction.prototype.hashForWitnessV0 = function (inIndex, prevOutScript, amoun
     hashOutputs = bcrypto.hash256(tbuffer)
   }
 
-  hashPrevouts = hashPrevouts || ZERO
-  hashSequence = hashSequence || ZERO
-  hashOutputs = hashOutputs || ZERO
-
   tbuffer = new Buffer(156 + varSliceSize(prevOutScript))
   toffset = 0