我有myService
使用myOtherService
,它可以进行远程调用,并返回promise:
angular.module('app.myService', ['app.myOtherService'])
.factory('myService', [
myOtherService,
function(myOtherService) {
function makeRemoteCall() {
return myOtherService.makeRemoteCallReturningPromise();
}
return {
makeRemoteCall: makeRemoteCall
};
}
])
要对myService
我进行单元测试,需要模拟myOtherService
,以便其makeRemoteCallReturningPromise
方法返回promise。这是我的方法:
describe('Testing remote call returning promise', function() {
var myService;
var myOtherServiceMock = {};
beforeEach(module('app.myService'));
// I have to inject mock when calling module(),
// and module() should come before any inject()
beforeEach(module(function ($provide) {
$provide.value('myOtherService', myOtherServiceMock);
}));
// However, in order to properly construct my mock
// I need $q, which can give me a promise
beforeEach(inject(function(_myService_, $q){
myService = _myService_;
myOtherServiceMock = {
makeRemoteCallReturningPromise: function() {
var deferred = $q.defer();
deferred.resolve('Remote call result');
return deferred.promise;
}
};
}
// Here the value of myOtherServiceMock is not
// updated, and it is still {}
it('can do remote call', inject(function() {
myService.makeRemoteCall() // Error: makeRemoteCall() is not defined on {}
.then(function() {
console.log('Success');
});
}));
从上面可以看到,我的模拟的定义取决于$q
,我必须使用来加载inject()
。此外,应该在中进行注入模拟module()
,这应该在之前进行inject()
。但是,一旦更改,该模拟的值就不会更新。
正确的方法是什么?
我不确定为什么您的方法行不通,但是我通常使用此spyOn
功能。像这样:
describe('Testing remote call returning promise', function() {
var myService;
beforeEach(module('app.myService'));
beforeEach(inject( function(_myService_, myOtherService, $q){
myService = _myService_;
spyOn(myOtherService, "makeRemoteCallReturningPromise").and.callFake(function() {
var deferred = $q.defer();
deferred.resolve('Remote call result');
return deferred.promise;
});
}
it('can do remote call', inject(function() {
myService.makeRemoteCall()
.then(function() {
console.log('Success');
});
}));
还要记住,您将需要$digest
调用要调用的then
函数。请参阅$ q文档的“测试”部分。
- - - 编辑 - - -
在仔细查看您的操作之后,我认为我在您的代码中看到了问题。在中beforeEach
,您将设置myOtherServiceMock
为一个新对象。将$provide
永远不会看到这个参考。您只需要更新现有参考:
beforeEach(inject( function(_myService_, $q){
myService = _myService_;
myOtherServiceMock.makeRemoteCallReturningPromise = function() {
var deferred = $q.defer();
deferred.resolve('Remote call result');
return deferred.promise;
};
}
我们还可以直接通过间谍编写茉莉的实现诺言的实现。
spyOn(myOtherService, "makeRemoteCallReturningPromise").andReturn($q.when({}));
对于茉莉花2:
spyOn(myOtherService, "makeRemoteCallReturningPromise").and.returnValue($q.when({}));
(摘自评论,感谢ccnokes)
describe('testing a method() on a service', function () {
var mock, service
function init(){
return angular.mock.inject(function ($injector,, _serviceUnderTest_) {
mock = $injector.get('service_that_is_being_mocked');;
service = __serviceUnderTest_;
});
}
beforeEach(module('yourApp'));
beforeEach(init());
it('that has a then', function () {
//arrange
var spy= spyOn(mock, 'actionBeingCalled').and.callFake(function () {
return {
then: function (callback) {
return callback({'foo' : "bar"});
}
};
});
//act
var result = service.actionUnderTest(); // does cleverness
//assert
expect(spy).toHaveBeenCalled();
});
});
您可以使用诸如sinon之类的存根库来模拟您的服务。然后,您可以返回$ q.when()作为您的承诺。如果范围对象的值来自promise结果,则需要调用scope。$ root。$ digest()。
var scope, controller, datacontextMock, customer;
beforeEach(function () {
module('app');
inject(function ($rootScope, $controller,common, datacontext) {
scope = $rootScope.$new();
var $q = common.$q;
datacontextMock = sinon.stub(datacontext);
customer = {id:1};
datacontextMock.customer.returns($q.when(customer));
controller = $controller('Index', { $scope: scope });
})
});
it('customer id to be 1.', function () {
scope.$root.$digest();
expect(controller.customer.id).toBe(1);
});
使用sinon
:
const mockAction = sinon.stub(MyService.prototype,'actionBeingCalled')
.returns(httpPromise(200));
已知httpPromise
可以是:
const httpPromise = (code) => new Promise((resolve, reject) =>
(code >= 200 && code <= 299) ? resolve({ code }) : reject({ code, error:true })
);
老实说..您通过依赖注入来模拟服务而不是模块来解决这种错误的方法。另外,在beforeEach中调用inject是一种反模式,因为它会使每个测试的模拟变得困难。
这就是我要怎么做...
module(function ($provide) {
// By using a decorator we can access $q and stub our method with a promise.
$provide.decorator('myOtherService', function ($delegate, $q) {
$delegate.makeRemoteCallReturningPromise = function () {
var dfd = $q.defer();
dfd.resolve('some value');
return dfd.promise;
};
});
});
现在,当您注入服务时,它将具有正确模拟的使用方法。
我发现有用的,刺入的服务功能为sinon.stub()。returns($ q.when({})):
this.myService = {
myFunction: sinon.stub().returns( $q.when( {} ) )
};
this.scope = $rootScope.$new();
this.angularStubs = {
myService: this.myService,
$scope: this.scope
};
this.ctrl = $controller( require( 'app/bla/bla.controller' ), this.angularStubs );
控制器:
this.someMethod = function(someObj) {
myService.myFunction( someObj ).then( function() {
someObj.loaded = 'bla-bla';
}, function() {
// failure
} );
};
并测试
const obj = {
field: 'value'
};
this.ctrl.someMethod( obj );
this.scope.$digest();
expect( this.myService.myFunction ).toHaveBeenCalled();
expect( obj.loaded ).toEqual( 'bla-bla' );
代码段:
spyOn(myOtherService, "makeRemoteCallReturningPromise").and.callFake(function() {
var deferred = $q.defer();
deferred.resolve('Remote call result');
return deferred.promise;
});
可以用更简洁的形式编写:
spyOn(myOtherService, "makeRemoteCallReturningPromise").and.returnValue(function() {
return $q.resolve('Remote call result');
});
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