Sergey,
I don't think that I agree with you here.
I do want to test the persistence. Not so much to verify that NHibernate works, but to verify that I am mapping all the properties that I think I should, that I can get assoication correctly, that the mapping is valid, etc.
Additionally, there is an issue when I want to use NHibernate for queries that contains business logic.
GetAllOutstandingLoads() - for instance, is something that you really should test, especially since most of the time it just construct a query and execute it.
s1mm0t,
There are several ways to test NHiberante:
Here is a favorite of mine:
http://www.ayende.com/Blog/archive/7183.aspx
Because of issues with SQLite data/time handling, and sharing several session on the same database, I moved to using SQL Server CE (embedded SQL).
Which still has the same properties as the previous test, even though it touches the filesystem