testing entity mapping of NHibernate - unit-testing

Question

i'm building some basic crud methods for my fluently mapped entities.
i just wanna know if there is a simple way to make the transaction to perform a rollback when i'm running the cud test methods ?
the code that being tested perform the commit inside
here is a create sample:
public int? Create(IIdentifiable entity)
{
int? newId = null;
using (ISession session = SessionFactoryProvider.NewSession)
using (ITransaction transaction = session.BeginTransaction())
{
object newObj = session.Save(entity);
newId = (int?)newObj;
transaction.Commit();
}
return (int?)newId;
}

Answer 1

If you're using xUnit.net, there's an AutoRollback attribute in the contrib project. If you're open to using System.Transactions then you can create a new transaction before the session.Open() and session should autoenlist (unless you've set ado.net to not autoenlist). Then just abandon at the end.
I did something similar to this a (long) while ago:
public class TransactionalTest
{
public TransactionalTest()
{
Transaction.Current = new CommittableTransaction();
}
~TransactionalTest()
{
if (Transaction.Current != null &&
Transaction.Current.TransactionInformation.Status !=
TransactionStatus.Committed)
{
Transaction.Current.Rollback();
}
}
}
Then just have your test extend TransactionalTest. But, I think NUnit, MbUnit and xUnit.net all support transactional tests out of the box or with a contrib project.

Answer 2

Check FUBUMVC Contrib for a great NHibernate CRUD testing method.

Answer 3

Hmm, I don't think that it is a good idea to let your method create a session and perform transaction handling .... Unless that method is also a service boundary.
Suppose you want to create multiple entities in one and the same transaction, how are you going to handle that ?

Answer 4

For integration testing, I use a session decorator to auto commit and evict the entity. You could adapt it for your situation:
public class AutoCommitAndEvictSession : SessionDecorator {
public AutoCommitAndEvictSession(ISession session)
: base(session) { }
public override object Save(object obj) {
object result;
using (var tx = Session.BeginTransaction()) {
result = Session.Save(obj);
tx.Commit();
}
Session.Evict(obj);
return result;
}
public override void Update(object obj) {
CommitAndEvict(base.Update, obj);
}
public override void Delete(object obj) {
CommitAndEvict(base.Delete, obj);
}
private void CommitAndEvict(Action<object> action, object entity) {
using (var tx = Session.BeginTransaction()) {
action.Invoke(entity);
tx.Commit();
}
Session.Evict(entity);
}
}
You can find more details on usage with examples here:
http://www.agileatwork.com/integration-testing-with-nhibernate/