Add `change` when serializing transaction

lib/address.js

@@ -112,6 +112,8 @@ Address.prototype._classifyArguments = function(data, network, type) {
     return Address._transformScript(data, network);
   } else if (typeof(data) === 'string') {
     return Address._transformString(data, network, type);
+  } else if (_.isObject(data)) {
+    return Address._transformObject(data);
   } else {
     throw new TypeError('First argument is an unrecognized data format.');
   }
@@ -139,6 +141,23 @@ Address._transformHash = function(hash){
   return info;
 };
 
+/**
+ * Deserializes an address serialized through `Address#toObject()`
+ * @param {Object} data
+ * @param {string} data.hash - the hash that this address encodes
+ * @param {string} data.type - either 'pubkeyhash' or 'scripthash'
+ * @param {Network=} data.network - the name of the network associated
+ * @return {Address}
+ */
+Address._transformObject = function(data) {
+  $.checkArgument(data.hash, 'Must provide a `hash` property');
+  $.checkArgument(data.type, 'Must provide a `type` property');
+  data.hashBuffer = new Buffer(data.hash, 'hex');
+  data.network = Networks.get(data.network) || Networks.defaultNetwork;
+
+  return data;
+};
+
 /**
  * Internal function to discover the network and type based on the first data byte
  *

lib/transaction/transaction.js

@@ -202,6 +202,9 @@ Transaction.prototype.fromJSON = function(json) {
   outputs.forEach(function(output) {
     self.outputs.push(Output.fromJSON(output));
   });
+  if (json.change) {
+    this.change(json.change);
+  }
   this.version = json.version;
   this.nLockTime = json.nLockTime;
   return this;
@@ -217,6 +220,7 @@ Transaction.prototype.toObject = function toObject() {
     outputs.push(output.toObject());
   });
   return {
+    change: this._change ? this._change.toObject() : undefined,
     version: this.version,
     inputs: inputs,
     outputs: outputs,
@@ -232,6 +236,9 @@ Transaction.prototype.fromObject = function(transaction) {
   _.each(transaction.outputs, function(output) {
     self.addOutput(new Output(output));
   });
+  if (transaction.change) {
+    this.change(transaction.change);
+  }
   this.nLockTime = transaction.nLockTime;
   this.version = transaction.version;
 };

test/address.js

@@ -233,7 +233,7 @@ describe('Address', function() {
     it('should error because of unrecognized data format', function() {
       (function() {
         return new Address(new Error());
-      }).should.throw('First argument is an unrecognized data format.');
+      }).should.throw(bitcore.errors.InvalidArgument);
     });
 
     it('should error because of incorrect format for pubkey hash', function() {

test/transaction/transaction.js

@@ -213,6 +213,16 @@ describe('Transaction', function() {
     });
   });
 
+  describe('serialization', function() {
+    it('stores the change address correctly', function() {
+      var serialized = new Transaction()
+        .change(changeAddress)
+        .toObject();
+      var deserialized = new Transaction(serialized);
+      expect(deserialized._change.toString()).to.equal(changeAddress);
+    });
+  });
+
   describe('checked serialize', function() {
     it('fails if no change address was set', function() {
       var transaction = new Transaction()