fix(ngValue): set value property instead of attr

in case of input element set value using property instead of attribute
fixed #13984

Author: m-amr

src/ng/directive/input.js

@@ -1756,12 +1756,25 @@ var ngValueDirective = function() {
     compile: function(tpl, tplAttr) {
       if (CONSTANT_VALUE_REGEXP.test(tplAttr.ngValue)) {
         return function ngValueConstantLink(scope, elm, attr) {
-          attr.$set('value', scope.$eval(attr.ngValue));
+          var value = scope.$eval(attr.ngValue);
+          /**
+           *  input use 'value attribute' as default value if 'value property has no value'
+           *  but once set the 'value property' it will not read value from 'value attribute'
+           *  so we set both the value attribute and property here to avoid this problem.
+           */
+          attr.$set('value', value);
+          elm[0].value = value;
         };
       } else {
         return function ngValueLink(scope, elm, attr) {
           scope.$watch(attr.ngValue, function valueWatchAction(value) {
+            /**
+             *  input use 'value attribute' as default value if 'value property has no value'
+             *  but once set the 'value property' it will not read value from 'value attribute'
+             *  so we set both the value attribute and property here to avoid this problem.
+             */
             attr.$set('value', value);
+            elm[0].value = value;
           });
         };
       }

test/ng/directive/inputSpec.js

@@ -3046,6 +3046,23 @@ describe('input', function() {
       expect(inputElm[0].getAttribute('value')).toBe('something');
     });
 
+    it('should update the input "value" property and attribute after change the "value" property', function() {
+      var inputElm = helper.compileInput('<input type="text" ng-value="value">');
+
+      $rootScope.$apply(function() {
+        $rootScope.value = 'something';
+      });
+      expect(inputElm[0].value).toBe('something');
+      expect(inputElm[0].getAttribute('value')).toBe('something');
+
+      helper.changeInputValueTo('newValue');
+
+      $rootScope.$apply(function() {
+        $rootScope.value = 'anotherValue';
+      });
+      expect(inputElm[0].value).toBe('anotherValue');
+      expect(inputElm[0].getAttribute('value')).toBe('anotherValue');
+    });
 
     it('should evaluate and set constant expressions', function() {
       var inputElm = helper.compileInput('<input type="radio" ng-model="selected" ng-value="true">' +