public void SearchUser() { var userManager = new UserManager<ApplicationUser>(new TestUserStore()); IEnumerable<ApplicationUser> fake = new List<ApplicationUser> { new ApplicationUser{Activated=true,Email="*****@*****.**",FirstName="user1",LastName="user1",RoleId=0}, new ApplicationUser{Activated=true,Email="*****@*****.**",FirstName="user2",LastName="user2",RoleId=0}, new ApplicationUser{Activated=true,Email="*****@*****.**",FirstName="user3",LastName="user3",RoleId=0}, new ApplicationUser{Activated=true,Email="*****@*****.**",FirstName="user4",LastName="user4",RoleId=0} }.AsEnumerable(); userRepository.Setup(x => x.GetMany(It.IsAny<Expression<Func<ApplicationUser, bool>>>())).Returns(fake); AccountController contr = new AccountController(userService, userProfileService, goalService, updateService, commentService, followRequestService, followUserService, securityTokenService, userManager); IEnumerable<ApplicationUser> result = contr.SearchUser("u") as IEnumerable<ApplicationUser>; Assert.IsNotNull(result); Assert.AreEqual(4, result.Count(), "not matching"); }