javascript - Jasmine 测试AngularJS $ on

我想用茉莉花来测试我的打字稿角度代码，但是在运行它时出现此错误。


  TypeError：“未定义”不是对象（正在评估“ scope.LessonCtrl.statistic”）


我正在尝试测试以下代码：

export class LessonCtrl {
  scope: angular.IScope;
  statistic: Statistic;

  constructor($scope) {
    this.scope = $scope;
    this.statistic = new Statistic();
    this.scope.$on("timer-stopped", function(event, data) {
      var scope: any = event.currentScope;
      scope.LessonCtrl.statistic.calculateTypingSpeed(data.millis);
      scope.LessonCtrl.statistic.setTime(data.millis);
    });
  }
}

有了这个：

var scope, rootScope, lessonCtrl;

beforeEach(() => inject(($rootScope) => {
  scope = $rootScope.$new();
  rootScope = $rootScope;
  lessonCtrl = new Controllers.LessonCtrl(scope);
}));

it('on test', () => {
  rootScope.$broadcast('timer-stopped', [{millis: 1000}]);
  expect(true).toBe(true); // i will expect something else but i have errors
});

谁能帮我这个？

最佳答案

您将statistic分配给上下文（this），而不是scope.LessonCtrl。通过使用arrow function the context will be preserved inside the .$on callback


  箭头函数捕获封闭上下文的此值。

export class LessonCtrl {
  scope: angular.IScope;
  statistic: Statistic;

  constructor($scope) {
    this.scope = $scope;
    this.statistic = new Statistic();
    this.scope.$on("timer-stopped", (event, data) => {
      var scope: any = event.currentScope;
      this.statistic.calculateTypingSpeed(data.millis);
      this.statistic.setTime(data.millis);
    });
  }
}