public async Task When__UserStore_Add_Login__Expect__Login_Added()
{
UserLoginInfo login = new UserLoginInfo("Google", "E5A1F645-088A-4984-A7CE-CA1D48D30F92");
int userId = 1;
ApplicationUser user = await _userStore.FindByIdAsync(userId).ConfigureAwait(false);
Assert.That(user, Is.Not.Null, "User not found");
await _userStore.AddLoginAsync(user, login).ConfigureAwait(false);
_context.SaveChanges();
IList <UserLoginInfo> logins = await _userStore.GetLoginsAsync(user).ConfigureAwait(false);
UserLoginInfo savedLogin = logins.Where(p =>
p.LoginProvider == login.LoginProvider &&
p.ProviderKey == login.ProviderKey).FirstOrDefault();
Assert.That(savedLogin, Is.Not.Null, "Login not added");
}