From 8b285c6c830d84b39f355c72db3e931fdb785130 Mon Sep 17 00:00:00 2001
From: Brad Dunbar <dunbarb2@gmail.com>
Date: Tue, 14 Feb 2012 15:22:27 -0500
Subject: [PATCH] `on` is a noop if no callback is provided

---
 backbone.js    | 1 +
 test/events.js | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/backbone.js b/backbone.js
index a8127af0..d10093d6 100644
--- a/backbone.js
+++ b/backbone.js
@@ -86,6 +86,7 @@
     // function. Passing `"all"` will bind the callback to all events fired.
     on: function(events, callback, context) {
       var ev;
+      if (!callback) return this;
       events = events.split(/\s+/);
       var calls = this._callbacks || (this._callbacks = {});
       while (ev = events.shift()) {
diff --git a/test/events.js b/test/events.js
index bb2aeb05..2c8f3e15 100644
--- a/test/events.js
+++ b/test/events.js
@@ -145,4 +145,8 @@ $(document).ready(function() {
     equal(counter, 2, 'unbind does not alter callback list');
   });
 
+  test("if no callback is provided, `on` is a noop", function() {
+    _.extend({}, Backbone.Events).bind('test').trigger('test');
+  });
+
 });