fixup: Object.assign()

Author: Trott

lib/zlib.js

@@ -454,7 +454,7 @@ Zlib.prototype.flush = function(kind, callback) {
 };
 
 Zlib.prototype.close = function(callback, options) {
-  options = options || {};
+  options = Object.assign({sync: false}, options);
 
   if (callback)
     process.nextTick(callback);