Feature/disable backspace reset

src/common.js

@@ -104,7 +104,8 @@ var uis = angular.module('ui.select', [])
   generateId: function() {
     return latestId++;
   },
-  appendToBody: false
+  appendToBody: false,
+  disableBackspaceReset: false
 })
 
 // See Rename minErr and make it accessible from outside https://github.com/angular/angular.js/issues/6913

src/uiSelectDirective.js

@@ -82,6 +82,11 @@ uis.directive('uiSelect',
             $select.searchEnabled = searchEnabled !== undefined ? searchEnabled : uiSelectConfig.searchEnabled;
         });
 
+        scope.$watch('disableBackspaceReset', function() {
+          var disableBackspaceReset = scope.$eval(attrs.disableBackspaceReset);
+          $select.disableBackspaceReset = disableBackspaceReset !== undefined ? disableBackspaceReset : uiSelectConfig.disableBackspaceReset;
+        });
+
         scope.$watch('sortable', function() {
             var sortable = scope.$eval(attrs.sortable);
             $select.sortable = sortable !== undefined ? sortable : uiSelectConfig.sortable;

src/uiSelectSingleDirective.js

@@ -84,8 +84,7 @@ uis.directive('uiSelectSingle', ['$timeout','$compile', function($timeout, $comp
         });
       });
       focusser.bind("keydown", function(e){
-
-        if (e.which === KEY.BACKSPACE) {
+        if (e.which === KEY.BACKSPACE && $select.disableBackspaceReset === false) {
           e.preventDefault();
           e.stopPropagation();
           $select.select(undefined);