refactor($controller): Add $controller service for instantiating controllers

So that we can allow user to override this service and use BC hack:
https://gist.github.com/1649788

angularFiles.js

@@ -13,6 +13,7 @@ angularFiles = {
     'src/service/browser.js',
     'src/service/cacheFactory.js',
     'src/service/compiler.js',
+    'src/service/controller.js',
     'src/service/cookieStore.js',
     'src/service/cookies.js',
     'src/service/defer.js',

src/AngularPublic.js

@@ -70,6 +70,7 @@ function publishExternalAPI(angular){
       $provide.service('$browser', $BrowserProvider);
       $provide.service('$cacheFactory', $CacheFactoryProvider);
       $provide.service('$compile', $CompileProvider);
+      $provide.service('$controller', $ControllerProvider);
       $provide.service('$cookies', $CookiesProvider);
       $provide.service('$cookieStore', $CookieStoreProvider);
       $provide.service('$defer', $DeferProvider);

src/directives.js

@@ -160,12 +160,12 @@ angularDirective("ng:init", function(expression){
  */
 angularDirective("ng:controller", function(expression) {
   this.scope(true);
-  return ['$injector', '$window', function($injector, $window) {
+  return ['$controller', '$window', function($controller, $window) {
     var scope = this,
         Controller = getter(scope, expression, true) || getter($window, expression, true);
 
     assertArgFn(Controller, expression);
-    $injector.instantiate(Controller, {$scope: scope});
+    $controller(Controller, scope);
   }];
 });
 

src/service/controller.js

@@ -0,0 +1,26 @@
+'use strict';
+
+function $ControllerProvider() {
+  this.$get = ['$injector', function($injector) {
+
+    /**
+     * @ngdoc function
+     * @name angular.module.ng.$controller
+     * @requires $injector
+     *
+     * @param {Function} Class Constructor function of a controller to instantiate.
+     * @param {Object} scope Related scope.
+     * @return {Object} Instance of given controller.
+     *
+     * @description
+     * `$controller` service is responsible for instantiating controllers.
+     *
+     * It's just simple call to {@link angular.module.AUTO.$injector $injector}, but extracted into
+     * a service, so that one can override this service with {@link https://gist.github.com/1649788
+     * BC version}.
+     */
+    return function(Class, scope) {
+      return $injector.instantiate(Class, {$scope: scope});
+    };
+  }];
+}

src/service/formFactory.js

@@ -102,8 +102,8 @@
 
 function $FormFactoryProvider() {
   var $parse;
-  this.$get = ['$rootScope', '$parse', '$injector',
+  this.$get = ['$rootScope', '$parse', '$controller',
-      function($rootScope, $parse_, $injector) {
+      function($rootScope, $parse_, $controller) {
     $parse = $parse_;
     /**
      * @ngdoc proprety
@@ -136,7 +136,7 @@ function $FormFactoryProvider() {
 
     function formFactory(parent) {
       var scope = (parent || formFactory.rootForm).$new();
-      $injector.instantiate(FormController, {$scope: scope});
+      $controller(FormController, scope);
       return scope;
     }
 

src/service/route.js

@@ -63,8 +63,8 @@
     </doc:example>
  */
 function $RouteProvider(){
-  this.$get = ['$rootScope', '$location', '$routeParams', '$injector',
+  this.$get = ['$rootScope', '$location', '$routeParams', '$controller',
-      function( $rootScope,  $location,  $routeParams, $injector) {
+      function( $rootScope,  $location,  $routeParams, $controller) {
     /**
      * @ngdoc event
      * @name angular.module.ng.$route#$beforeRouteChange
@@ -280,7 +280,7 @@ function $RouteProvider(){
             copy(next.params, $routeParams);
             next.scope = parentScope.$new();
             if (next.controller) {
-              $injector.instantiate(next.controller, {$scope: next.scope});
+              $controller(next.controller, next.scope);
             }
           }
         }

test/service/controllerSpec.js

@@ -0,0 +1,38 @@
+'use strict';
+
+describe('$controller', function() {
+  var $controller;
+
+  beforeEach(inject(function($injector) {
+    $controller = $injector.get('$controller');
+  }));
+
+  it('should return instance of given controller class', function() {
+    var MyClass = function() {},
+        ctrl = $controller(MyClass);
+
+    expect(ctrl).toBeDefined();
+    expect(ctrl instanceof MyClass).toBe(true);
+  });
+
+  it('should inject arguments', inject(function($http) {
+    var MyClass = function($http) {
+      this.$http = $http;
+    };
+
+    var ctrl = $controller(MyClass);
+    expect(ctrl.$http).toBe($http);
+  }));
+
+
+  it('should inject given scope', function() {
+    var MyClass = function($scope) {
+      this.$scope = $scope;
+    };
+
+    var scope = {},
+        ctrl = $controller(MyClass, scope);
+
+    expect(ctrl.$scope).toBe(scope);
+  });
+});