fix(ngBindHtml): clear contents when model is falsy

Closes #864

Author: IgorMinar

src/ng/directive/ngBind.js

@@ -73,7 +73,7 @@ var ngBindDirective = ngDirective(function(scope, element, attr) {
 var ngBindHtmlUnsafeDirective = ngDirective(function(scope, element, attr) {
   element.addClass('ng-binding').data('$binding', attr.ngBindHtmlUnsafe);
   scope.$watch(attr.ngBindHtmlUnsafe, function(value) {
-    element.html(value == undefined ? '' : value);
+    element.html(value || '');
   });
 });
 
@@ -96,9 +96,8 @@ var ngBindHtmlDirective = ['$sanitize', function($sanitize) {
   return function(scope, element, attr) {
     element.addClass('ng-binding').data('$binding', attr.ngBindHtml);
     scope.$watch(attr.ngBindHtml, function(value) {
-      if (value = $sanitize(value)) {
-        element.html(value);
-      }
+      value = $sanitize(value);
+      element.html(value || '');
     });
   }
 }];

test/ng/directive/ngBindSpec.js

@@ -82,6 +82,21 @@ describe('ng-bind-*', function() {
       $rootScope.$digest();
       expect(lowercase(element.html())).toEqual('<div>hello</div>');
     }));
+
+
+    it('should reset html when value is null or undefined', inject(function($compile, $rootScope) {
+      element = $compile('<div ng-bind-html="html"></div>')($rootScope);
+
+      forEach([null, undefined, ''], function(val) {
+        $rootScope.html = 'some val';
+        $rootScope.$digest();
+        expect(lowercase(element.html())).toEqual('some val');
+
+        $rootScope.html = val;
+        $rootScope.$digest();
+        expect(lowercase(element.html())).toEqual('');
+      });
+    }));
   });