User name and email uniqueness should be enforced

[orchardbot]

@bradmi created:
https://orchard.codeplex.com/workitem/14887

Symptom: Log in throws System.InvalidOperationException: Sequence contains more than one element

1. Click Log In link
2. Click Register to create a new account and sign in
3. Click Log Out link to sign out
4. Click Log In link again
5. Attempt to sign in with previously specified credentials

RESULT:

Sequence contains more than one element
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidOperationException: Sequence contains more than one element

Source Error:

Line 97:
Line 98: public virtual T Get(Expression<Func<T, bool>> predicate) {
Line 99: return Fetch(predicate).SingleOrDefault();
Line 100: }
Line 101:

Source File: C:\Orchard\trunk\src\Orchard\Data\Repository.cs Line: 99

Stack Trace:
[InvalidOperationException: Sequence contains more than one element]
System.Linq.Enumerable.SingleOrDefault(IEnumerable1 source) +733860 NHibernate.Linq.Visitors.ImmediateResultsVisitor1.HandleSingleOrDefaultCall(MethodCallExpression call) +62
NHibernate.Linq.Visitors.ImmediateResultsVisitor1.VisitMethodCall(MethodCallExpression call) +408 NHibernate.Linq.Visitors.ExpressionVisitor.Visit(Expression exp) +341 NHibernate.Linq.Visitors.NHibernateExpressionVisitor.Visit(Expression exp) +204 NHibernate.Linq.Visitors.ImmediateResultsVisitor1.GetResults(MethodCallExpression expr) +12
NHibernate.Linq.Visitors.RootVisitor.HandleImmediateResultsCall(MethodCallExpression call) +174
NHibernate.Linq.Visitors.RootVisitor.VisitMethodCall(MethodCallExpression expr) +703
NHibernate.Linq.Visitors.ExpressionVisitor.Visit(Expression exp) +341

[orchardbot]

@loudej commented:

The problem is a user name is not unique. For now, use the admin interface to change one of the user's names.