服务承诺不解决业力

service promise not resolving with karma

我有一个 service factory 可以连接 api 并与之交互以获取数据。这是服务:

angular.module('dbRequest', [])
  .factory('Request', ['$http', 'localConfig', function($http, localConfig){
    return {
      getDataRevision: function(){
        return $http({
          url: localConfig.dbDataUrl,
          method: "GET",
          crossDomain: true,
          headers: {
            'Content-Type': 'application/json; charset=utf-8'
          }
        })
      }
    }
  }]);

根据 this answer 的提示,这就是我测试该方法的方式:

describe('Service: Request', function () {
  var $scope, srvMock, $q, lc, $httpBackend;

  beforeEach(module('webApp'));

  beforeEach(inject(function($rootScope, Request, _$q_, _$httpBackend_, localConfig){
    $scope = $rootScope.$new();
    srvMock = Request;
    $q = _$q_;
    $httpBackend = _$httpBackend_;
    lc = localConfig;

    $httpBackend.expect('GET', lc.dbDataUrl);

    $httpBackend.when('GET', lc.dbDataUrl).respond({
      success: ["d1","d2", "d3"]
    });
  }));

  it('should return a promise', function(){
    expect(srvMock.getDataRevision().then).toBeDefined();
  });

  it('should resolve with data', function(){
    var data;
    var deferred = $q.defer();
    var promise = deferred.promise;

    promise.then(function(res){
      data = res.success;
    });

    srvMock.getDataRevision().then(function(res){
      deferred.resolve(res);
    });

    $scope.$digest();

    expect(data).toEqual(["d1","d2", "d3"]);
  })
});

should return a promise 通过,但下一个 should resolve with data 失败并出现此错误:

Expected undefined to equal [ 'd1', 'd2', 'd3' ].

然而,service 方法 getDataRevision 被调用,但未被测试中的模拟承诺解析。我该如何更正?

目前您希望模拟数据存在于 data 变量中而不刷新 httpRequests,但这不会发生,直到您 flush 所有 httpRequest秒。 $httpBackend.flush() 所做的是,它 returns 模拟您使用 $httpBackend.when('GET', lc.dbDataUrl).respond.

所做的特定请求的数据

此外,您不需要创建额外的承诺,这将是一项开销。您可以使用服务函数返回承诺本身,而不是自定义承诺,如下所示。

代码

it('should resolve with data', function(){
    var data;

    srvMock.getDataRevision().then(function(res){
      data = res.success;
    });

    $scope.$digest();
    $httpBackend.flush(); //making sure mocked response has been return
    //after .then evaluation only below code will get called.
    expect(data).toEqual(["d1","d2", "d3"]);
})