public void ReturnCorrectFriendsIds() { // Arrange int userId = 10; var mockedUserFriendRepository = new Mock <IEFRepository <UserFriend> >(); var friendShips = new List <UserFriend>() { new UserFriend() { UserId = userId, FriendId = 2 }, new UserFriend() { UserId = 50, FriendId = 1 }, new UserFriend() { UserId = userId, FriendId = 3 } }.AsQueryable(); mockedUserFriendRepository.Setup(x => x.All).Returns(friendShips); var mockedUserRepository = new Mock <IEFRepository <CustomUser> >(); var mockedUserFriendFactory = new Mock <IUserFriendFactory>(); var mockedUnitOfWork = new Mock <IUnitOfWork>(); var friendService = new FriendService( mockedUserFriendRepository.Object, mockedUserRepository.Object, mockedUserFriendFactory.Object, mockedUnitOfWork.Object); var expected = new List <int>() { 2, 3 }; // Act var result = friendService.GetAllUserFriendsIds(userId); // Assert CollectionAssert.AreEqual(result, expected); }