Add support for combination of manual and automatic bindings to Backbone ModelBinder

gistfile1.diff

diff --git a/static/js/lib/Backbone.ModelBinder.js b/static/js/lib/Backbone.ModelBinder.js
index b321c37..53881b1 100644
--- a/static/js/lib/Backbone.ModelBinder.js
+++ b/static/js/lib/Backbone.ModelBinder.js
@@ -25,6 +25,10 @@
 
             this._model = model;
             this._rootEl = rootEl;
+            this._attributeBindings = {};
+            this._options = { // TODO: set this properly
+                alwaysDefaultBindings: true
+            };
 
             if (!this._model) throw 'model must be specified';
             if (!this._rootEl) throw 'rootEl must be specified';
@@ -54,10 +58,7 @@
         _initializeAttributeBindings:function () {
             var attributeBindingKey, inputBinding, attributeBinding, elementBindingCount, elementBinding;
 
-            if(!this._attributeBindings){
-                this._initializeDefaultAttributeBindings();
-            }
-            else {
+            if(this._attributeBindings){
                 for (attributeBindingKey in this._attributeBindings) {
                     inputBinding = this._attributeBindings[attributeBindingKey];
 
@@ -86,13 +87,24 @@
 
                 this._initializeElBindings();
             }
+
+            if(!this._attributeBindings || this._options.alwaysDefaultBindings){
+                this._initializeDefaultAttributeBindings();
+            }
         },
 
         _initializeDefaultAttributeBindings: function(){
             var elCount, namedEls, namedEl, name;
-            this._attributeBindings = {};
             namedEls = $('[name]', this._rootEl);
 
+            // If we're using combination of default and manual bindings, prevent manual ones from having defaults applied
+            if(this._options.alwaysDefaultBindings){
+                namedEls = _.filter(namedEls, function(namedEl){
+                    var name = $(namedEl).attr('name');
+                    return !(name in this);
+                }, this._attributeBindings);
+            }
+
             for(elCount = 0; elCount < namedEls.length; elCount++){
                 namedEl = namedEls[elCount];
                 name = $(namedEl).attr('name');