如何在不设置nhibernate会话的情况下测试软删除事件列表器

我已根据此源重写默认nHibernate DefaultDeleteEventListener: http://nhibernate.info/blog/2008/09/06/soft-deletes.html

所以我有

 protected override void DeleteEntity(
        IEventSource session,
        object entity,
        EntityEntry entityEntry,
        bool isCascadeDeleteEnabled,
        IEntityPersister persister,
        ISet transientEntities)
    {
        if (entity is ISoftDeletable)
        {
            var e = (ISoftDeletable)entity;
            e.DateDeleted = DateTime.Now;
            CascadeBeforeDelete(session, persister, entity, entityEntry, transientEntities);
            CascadeAfterDelete(session, persister, entity, transientEntities);
        }
        else
        {
            base.DeleteEntity(session, entity, entityEntry, isCascadeDeleteEnabled, persister, transientEntities);
        }
    }

如何只测试这段代码,而不配置nhibernate会话?