feat($time): create time service

Add simple $time service to allow easier mocking dates in applications.

Closes angular#10402

Author: marcin-wosinek

angularFiles.js

@@ -37,6 +37,7 @@ var angularFiles = {
     'src/ng/sniffer.js',
     'src/ng/templateRequest.js',
     'src/ng/testability.js',
+    'src/ng/time.js',
     'src/ng/timeout.js',
     'src/ng/urlUtils.js',
     'src/ng/window.js',

src/AngularPublic.js

@@ -80,6 +80,7 @@
   $TemplateCacheProvider,
   $TemplateRequestProvider,
   $$TestabilityProvider,
+  $TimeProvider,
   $TimeoutProvider,
   $$RAFProvider,
   $$AsyncCallbackProvider,
@@ -234,6 +235,7 @@ function publishExternalAPI(angular) {
         $templateCache: $TemplateCacheProvider,
         $templateRequest: $TemplateRequestProvider,
         $$testability: $$TestabilityProvider,
+        $time: $TimeProvider,
         $timeout: $TimeoutProvider,
         $window: $WindowProvider,
         $$rAF: $$RAFProvider,

src/ng/time.js

@@ -0,0 +1,43 @@
+'use strict';
+
+/**
+ * @ngdoc service
+ * @name $time
+ * @requires $window
+ *
+ * @description
+ * Simple service for accessing time.
+ *
+ * The main purpose of this service is to simplify mocking time in tests.
+ *
+ * @example
+   <example module="timeExample">
+     <file name="script.js">
+       angular.module('timeExample', [])
+         .controller('TimeController', ['$scope', '$time', function($scope, $time) {
+           $scope.now = $time.now();
+         }]);
+     </file>
+     <file name="index.html">
+       <div ng-controller="TimeController">
+         <p>Time when the page was created: {{now | date}}</p>
+       </div>
+     </file>
+   </example>
+ */
+function $TimeProvider() {
+  var self = this;
+
+  this.$get = ['$window', function($window) {
+    return {
+      /**
+       * @ngdoc method
+       * @name $time#now
+       *
+       * @description
+       * Return current date getter
+       */
+      now: $window.Date.now
+    };
+  }];
+}

test/ng/timeSpec.js

@@ -0,0 +1,26 @@
+/* global $TimeProvider: false */
+'use strict';
+
+describe('$time', function() {
+  var $window;
+
+  beforeEach(module(function($provide) {
+    $window = {Date: {
+    }};
+
+    $provide.value('$window', $window);
+  }));
+
+  it('should return Date.new() when $time.now() is called', inject(
+    function() {
+      $window.Date.now = function() {
+        return 1418982310112;
+      };
+    },
+    function($time) {
+      var time = $time.now();
+      expect(time).toEqual(1418982310112);
+    }
+  ));
+
+});