Minmal Repro for NHibernate issues (SSCCE / MCVE)

NHibernateUnitTests.cs

/* Gist for minimal repro for NHibernate issues
 * 
 * 1. Create new (e.g. .NET 4.5.1) class library;
 * 2. Add NHibernate (e.g. 4.0.3) via NuGet;
 * 3. Add FluentNHibernate (e.g. 2.0.1) via NuGet;
 * 4. Add NUnit (e.g. 2.6.4) via NuGet;
 * 5. Create database "NhTestDb" on Sql Server "localhost" (or adjust for your specific situation);
 * 6. Compile;
 * 7. Run tests (should be green).
 * 
*/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using FluentNHibernate.Cfg;
using FluentNHibernate.Cfg.Db;
using FluentNHibernate.Mapping;
using NHibernate;
using NHibernate.Tool.hbm2ddl;
using NUnit.Framework;

namespace MyTestLibrary
{
    public class Item
    {
        public virtual int Id { get; set; }
    }

    public class ItemMap : ClassMap<Item>
    {
        public ItemMap()
        {
            Id(i => i.Id);
        }
    }

    [TestFixture]
    public class MyTestFixture
    {
        const string connectionString = @"data source=localhost; Integrated Security=SSPI; Initial Catalog=NhTestDb";

        private ISessionFactory sessionFactory;

        [TestFixtureSetUp]
        public void TestFixtureSetUp()
        {
            sessionFactory = Fluently.Configure()
                .Database(MsSqlConfiguration.MsSql2012.ConnectionString(connectionString))
                .Mappings(m => m.FluentMappings.AddFromAssembly(Assembly.GetExecutingAssembly()))
                .ExposeConfiguration(cfg => new SchemaExport(cfg).Create(true, true))
                .BuildSessionFactory();
        }

        [Test]
        public void MyTest001()
        {
            var session = sessionFactory.OpenSession();
            var item = new Item();

            using (var transaction = session.BeginTransaction())
            {
                session.Save(item);
                transaction.Commit();
            }

            Assert.That(item.Id, Is.Not.EqualTo(default(int)));
        }
    }
}