From ea9d49b15ef99c3460a0dc03f49183c9bc2c0aee Mon Sep 17 00:00:00 2001
From: Toby Zerner <toby.zerner@gmail.com>
Date: Sat, 2 May 2015 08:46:38 +0930
Subject: [PATCH] Allow extensions to easily override a function and call super

---
 js/lib/extension-utils.js | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/js/lib/extension-utils.js b/js/lib/extension-utils.js
index c54bcfc06..55712bace 100644
--- a/js/lib/extension-utils.js
+++ b/js/lib/extension-utils.js
@@ -1,8 +1,16 @@
 export function extend(object, func, extension) {
   var oldFunc = object[func];
   object[func] = function() {
-    var value = oldFunc.apply(this, arguments);
     var args = [].slice.apply(arguments);
+    var value = oldFunc.apply(this, args);
     return extension.apply(this, [value].concat(args));
   }
 };
+
+export function override(object, func, override) {
+  var parent = object[func];
+  object[func] = function() {
+    var args = [].slice.apply(arguments);
+    return override.apply(this, [parent].concat(args));
+  }
+}