如何使用 angularJS-karma-jasmine 测试指令的控制器？

Goal:

为以下内容编写一个通过测试waCarousel指令范围变量：self.awesomeThings。预计此测试通过时self.awsomeThings.length.toBe(3)是真的吗？

问题：

我怎样才能正确地编写这个测试？相反，我如何注入指令控制器？

指示：

angular.module('carouselApp')
    .directive('waCarousel', function() {
        return {
            templateUrl: '../../../views/carousel/wa.carousel.html',
            controller: function($scope) {
                var self = this;

                self.awesomeThings = [1, 2, 3];

                return $scope.carousel = self;
            }
        }
    });

单元测试：

describe('waCarousel Unit', function() {
  // am I missing a $controller & namespace variable init?
   var $compile,
      $rootScope;


  // Load the myApp module, which contains the directive
  beforeEach(module('carouselApp'));

  // Store references to $rootScope and $compile and $controller
  // so they are available to all tests in this describe block
  beforeEach(inject(function(_$compile_, _$rootScope_, _$controller_){
    // The injector unwraps the underscores (_) from around the parameter names when matching
    $compile = _$compile_;
    $rootScope = _$rootScope_;
    $controller = _$controller_;
     //   WaCarouselCtrl = $controller('WaCarouselCtrl', {
     //       $scope: scope
     //   });
  }));

  it('should have a list of awesomeThings', function() {
    // This wont pass       
    expect(scope.awesomeThings.length).toBe(3);
  });
});

这就是我对于典型视图而不是指令的做法：

describe('Controller: MainCtrl', function() {

    // load the controller's module
    beforeEach(module('carouselApp'));

    var MainCtrl,
        scope;

    // Initialize the controller and a mock scope
    beforeEach(inject(function($controller, $rootScope) {
        scope = $rootScope.$new();
        // !!*** this is how I would inject the typical controller of a view **!! //
        MainCtrl = $controller('MainCtrl', {
            $scope: scope
        });
    }));

    it('should attach a list of awesomeThings to the scope', function() {
        expect(scope.awesomeThings.length).toBe(3);
    });
});

我如何合并这两个概念以便我可以期望self.awesomeThings.length).toBe(3)?

UPDATE:

Compile https://docs.angularjs.org/api/ng/service/%24compile元素，并在调用后$digest() https://docs.angularjs.org/api/ng/type/%24rootScope.Scope#%24digest，您将有权访问包含以下内容的范围carousel对象与awesomeThings array:

describe('waCarousel Unit', function() {
    var scope;

    beforeEach(module('carouselApp'));
    beforeEach(inject(function($rootScope, $compile) {
        var element = '<test></test>';

        scope = $rootScope.$new();

        element = $compile(element)(scope);
        scope.$digest();
    }));

    it('should have a list of awesomeThings', function() {    
        expect(scope.carousel.awesomeThings.length).toBe(3);
    });
});

另外，这里还有一些有用的链接来测试 Angular 指令：

• 测试指令 https://docs.angularjs.org/guide/unit-testing#testing-directives
• 使用 Jasmine 和 Karma 测试 AngularJS 指令控制器 http://daginge.com/technology/2014/03/03/testing-angular-directive-controllers-with-jasmine-and-karma/
• 单元测试简介：指令 http://angular-tips.com/blog/2014/06/introduction-to-unit-test-directives/