util: use Object.keys() in _.extend

yyx990803 · yyx990803 · commit 559768d6e388 · 2015-10-03T13:35:34.000-04:00
diff --git a/src/util/lang.js b/src/util/lang.js
@@ -163,8 +163,10 @@ exports.toArray = function (list, start) {
  */
 
 exports.extend = function (to, from) {
-  for (var key in from) {
-    to[key] = from[key]
+  var keys = Object.keys(from)
+  var i = keys.length
+  while (i--) {
+    to[keys[i]] = from[keys[i]]
   }
   return to
 }

Original file line number	Diff line number	Diff line change
`@@ -163,8 +163,10 @@ exports.toArray = function (list, start) {`
`163`	`163`	`*/`
`164`	`164`
`165`	`165`	`exports.extend = function (to, from) {`
`166`		`- for (var key in from) {`
`167`		`- to[key] = from[key]`
	`166`	`+ var keys = Object.keys(from)`
	`167`	`+ var i = keys.length`
	`168`	`+ while (i--) {`
	`169`	`+ to[keys[i]] = from[keys[i]]`
`168`	`170`	`}`
`169`	`171`	`return to`
`170`	`172`	`}`