public void Username_Duplicated()
{
var userFirst = testCtx.UserAuthentications.First();
var userLast = testCtx.UserAuthentications.Last();
userFirst.Username = un;
userLast.Username = un;
testCtx.SaveChanges();
var result = uManager.AddPasswordAsync(new NuApplicationUser(un), pwd).Result;
Assert.IsFalse(result.Succeeded);
Assert.AreEqual(result.Errors.Count(), 1);
Assert.AreEqual(AppMessages.DuplicateUsername(un), result.Errors.First().Description);
}
