public async void GetSpeakerSessionCollection_OkResult() { var sessionObject = new RootObject() { Collection = new Collection() { Items = new List<ResponseItem>() { new ResponseItem() { Id = 1 }, new ResponseItem() { Id = 2 }, new ResponseItem() { Id = 3 } } } }; var speakerObject = new RootObject() { Collection = new Collection() { Items = new List<ResponseItem>() { new ResponseItem() { Id = 1 }, new ResponseItem() { Id = 2 } } } }; httpClientService.GetAsync<RootObject>("sessions").Returns<RootObject>(sessionObject); httpClientService.GetAsync<RootObject>("speakers").Returns<RootObject>(speakerObject); var result = await conferenceService.GetCollectionAsync(); var model = Assert.IsAssignableFrom<SpeakerSessionCollection>( result); Assert.Equal(3, model.SessionsList.Count); Assert.Equal(2, model.SpeakersList.Count); }