Down integrate to GitHub
diff --git a/js/map.js b/js/map.js
index b9a48af..589a293 100644
--- a/js/map.js
+++ b/js/map.js
@@ -461,15 +461,21 @@
* The BinaryReader parsing callback for type V, if V is a message type
*
* @param {K=} opt_defaultKey
- * The default value for the type of map keys. Accepting map
- * entries with unset keys is required for maps to be backwards compatible
- * with the repeated message representation described here: goo.gl/zuoLAC
+ * The default value for the type of map keys. Accepting map entries with
+ * unset keys is required for maps to be backwards compatible with the
+ * repeated message representation described here: goo.gl/zuoLAC
+ *
+ * @param {V=} opt_defaultValue
+ * The default value for the type of map values. Accepting map entries with
+ * unset values is required for maps to be backwards compatible with the
+ * repeated message representation described here: goo.gl/zuoLAC
*
*/
jspb.Map.deserializeBinary = function(map, reader, keyReaderFn, valueReaderFn,
- opt_valueReaderCallback, opt_defaultKey) {
+ opt_valueReaderCallback, opt_defaultKey,
+ opt_defaultValue) {
var key = opt_defaultKey;
- var value = undefined;
+ var value = opt_defaultValue;
while (reader.nextField()) {
if (reader.isEndGroup()) {
@@ -484,7 +490,11 @@
// Value.
if (map.valueCtor_) {
goog.asserts.assert(opt_valueReaderCallback);
- value = new map.valueCtor_();
+ if (!value) {
+ // Old generator still doesn't provide default value message.
+ // Need this for backward compatibility.
+ value = new map.valueCtor_();
+ }
valueReaderFn.call(reader, value, opt_valueReaderCallback);
} else {
value =
