multisig.input.encodestack - replace OP_0 (permitted by partialSignature) with EMPTY_BUFFER

src/templates/multisig/input.js

@@ -39,7 +39,12 @@ function encodeStack (signatures, scriptPubKey) {
     }
   }
 
-  return [].concat(EMPTY_BUFFER, signatures)
+  return [].concat(EMPTY_BUFFER, signatures.map(function (sig) {
+    if (sig === OPS.OP_0) {
+      return EMPTY_BUFFER
+    }
+    return sig
+  }))
 }
 
 function encode (signatures, scriptPubKey) {

src/transaction_builder.js

@@ -389,14 +389,14 @@ function buildStack (type, signatures, pubKeys, allowIncomplete) {
   } else if (type === scriptTypes.MULTISIG) {
     if (signatures.length > 0) {
       signatures = signatures.map(function (signature) {
-        return signature || Buffer.from('', 'hex')
+        return signature || ops.OP_0
       })
       if (!allowIncomplete) {
         // remove blank signatures
-        signatures = signatures.filter(function (x) { return x.length !== 0 })
+        signatures = signatures.filter(function (x) { return x !== ops.OP_0 })
       }
 
-      return [].concat(Buffer.from('', 'hex'), signatures)
+      return bscript.multisig.input.encodeStack(signatures)
     }
   } else {
     throw new Error('Not yet supported')