refactor(): create $mdUtil.fakeNgModel() for when no ngModel supplied

Author: ajoslin

src/components/checkbox/checkbox.js

@@ -46,9 +46,8 @@ angular.module('material.components.checkbox', [
  * </hljs>
  *
  */
-function MdCheckboxDirective(inputDirective, $mdInkRipple, $mdAria, $mdConstant, $mdTheming) {
+function MdCheckboxDirective(inputDirective, $mdInkRipple, $mdAria, $mdConstant, $mdTheming, $mdUtil) {
   inputDirective = inputDirective[0];
-
   var CHECKED_CSS = 'md-checked';
 
   return {
@@ -74,18 +73,10 @@ function MdCheckboxDirective(inputDirective, $mdInkRipple, $mdAria, $mdConstant,
     tElement.attr('role', tAttrs.type);
 
     return function postLink(scope, element, attr, ngModelCtrl) {
+      ngModelCtrl = ngModelCtrl || $mdUtil.fakeNgModel();
       var checked = false;
       $mdTheming(element);
 
-      // Create a mock ngModel if the user doesn't provide one
-      ngModelCtrl = ngModelCtrl || {
-        $setViewValue: function(value) {
-          this.$viewValue = value;
-        },
-        $parsers: [],
-        $formatters: []
-      };
-
       $mdAria.expectWithText(tElement, 'aria-label');
 
       // Reuse the original input[type=checkbox] directive from Angular core.

src/components/radioButton/radioButton.js

@@ -61,10 +61,8 @@ function mdRadioGroupDirective($mdUtil, $mdConstant, $mdTheming) {
 
   function linkRadioGroup(scope, element, attr, ctrls) {
     $mdTheming(element);
-    var rgCtrl = ctrls[0],
-      ngModelCtrl = ctrls[1] || {
-        $setViewValue: angular.noop
-      };
+    var rgCtrl = ctrls[0];
+    var ngModelCtrl = ctrls[1] || $mdUtil.fakeNgModel();
 
     function keydownListener(ev) {
       if (ev.keyCode === $mdConstant.KEY_CODE.LEFT_ARROW || ev.keyCode === $mdConstant.KEY_CODE.UP_ARROW) {

src/core/util/util.js

@@ -23,6 +23,18 @@ angular.module('material.core')
      */
     iterator: iterator,
 
+    fakeNgModel: function() {
+      return {
+        $setViewValue: function(value) {
+          this.$viewValue = value;
+          this.$render(value);
+        },
+        $parsers: [],
+        $formatters: [],
+        $render: angular.noop
+      };
+    },
+
     /**
      * @see cacheFactory below
      */