Strengthen asserts to verify actual locking has taken place

- Add test case to verify that a change in lock mode will avoid reusing cached query.

Author: oskarb

src/NHibernate.Test/Linq/QueryLock.cs

@@ -1,47 +1,115 @@
 using System.Linq;
-using NHibernate.AdoNet;
-using NHibernate.Cfg;
-using NHibernate.Engine;
+using System.Transactions;
+using NHibernate.Dialect;
+using NHibernate.DomainModel.Northwind.Entities;
+using NHibernate.Exceptions;
 using NHibernate.Linq;
 using NUnit.Framework;
 
+
 namespace NHibernate.Test.Linq
 {
 	public class QueryLock : LinqTestCase
 	{
-
 		[Test]
 		public void CanSetLockLinqQueries()
 		{
-			var result = (from e in db.Customers
-						  where e.CompanyName == "Corp"
-						  select e).SetLockMode(LockMode.Upgrade).ToList();
+			using (session.BeginTransaction())
+			{
+				var result = (from e in db.Customers
+				              select e).SetLockMode(LockMode.Upgrade).ToList();
 
+				Assert.That(result, Has.Count.EqualTo(91));
+				Assert.That(session.GetCurrentLockMode(result[0]), Is.EqualTo(LockMode.Upgrade));
+				AssertSeparateTransactionIsLockedOut(result[0].CustomerId);
+			}
 		}
 
 
 		[Test]
 		public void CanSetLockOnLinqPagingQuery()
 		{
-			var result = (from e in db.Customers
-						  where e.CompanyName == "Corp"
-						  select e).Skip(5).Take(5).SetLockMode(LockMode.Upgrade).ToList();
-		}
+			using (session.BeginTransaction())
+			{
+				var result = (from e in db.Customers
+				              select e).Skip(5).Take(5).SetLockMode(LockMode.Upgrade).ToList();
 
+				Assert.That(result, Has.Count.EqualTo(5));
+				Assert.That(session.GetCurrentLockMode(result[0]), Is.EqualTo(LockMode.Upgrade));
+				AssertSeparateTransactionIsLockedOut(result[0].CustomerId);
+			}
+		}
 
 		[Test]
 		public void CanLockBeforeSkipOnLinqOrderedPageQuery()
 		{
-			var result = (from e in db.Customers
-						  orderby e.CompanyName
-						  select e)
-				.SetLockMode(LockMode.Upgrade).Skip(5).Take(5).ToList();
+			using (session.BeginTransaction())
+			{
+				var result = (from e in db.Customers
+				              orderby e.CompanyName
+				              select e)
+				             .SetLockMode(LockMode.Upgrade).Skip(5).Take(5).ToList();
 
+				Assert.That(result, Has.Count.EqualTo(5));
+				Assert.That(session.GetCurrentLockMode(result[0]), Is.EqualTo(LockMode.Upgrade));
+				AssertSeparateTransactionIsLockedOut(result[0].CustomerId);
+			}
+		}
 
+		private void AssertSeparateTransactionIsLockedOut(string customerId)
+		{
+			using (new TransactionScope(TransactionScopeOption.Suppress))
+			using (var s2 = OpenSession())
+			using (s2.BeginTransaction())
+			{
+				// TODO: We should try to verify that the exception actually IS a locking failure and not something unrelated.
+				Assert.Throws<GenericADOException>(
+					() =>
+					{
+						var result2 = (
+								from e in s2.Query<Customer>()
+								where e.CustomerId == customerId
+								select e
+							).SetLockMode(LockMode.UpgradeNoWait)
+							 .WithOptions(o => o.SetTimeout(5))
+							 .ToList();
+						Assert.That(result2, Is.Not.Null);
+					},
+					"Expected an exception to indicate locking failure due to already locked.");
+			}
 		}
 
+		[Test]
+		[Description("Verify that different lock modes are respected even if the query is otherwise exactly the same.")]
+		public void CanChangeLockModeForQuery()
+		{
+			// Limit to a few dialects where we know the "nowait" keyword is used to make life easier.
+			Assume.That(Dialect is MsSql2000Dialect || Dialect is Oracle8iDialect || Dialect is PostgreSQL81Dialect);
+
+			using (session.BeginTransaction())
+			{
+				var result = BuildQueryableAllCustomers(db.Customers, LockMode.Upgrade).ToList();
+				Assert.That(result, Has.Count.EqualTo(91));
 
-	}
+				using (var logSpy = new SqlLogSpy())
+				{
+					// Only difference in query is the lockmode - make sure it gets picked up.
+					var result2 = BuildQueryableAllCustomers(session.Query<Customer>(), LockMode.UpgradeNoWait)
+						.ToList();
+					Assert.That(result2, Has.Count.EqualTo(91));
+
+					Assert.That(logSpy.GetWholeLog().ToLower(), Does.Contain("nowait"));
+				}
+			}
+		}
 
+		private static IQueryable<Customer> BuildQueryableAllCustomers(
+			IQueryable<Customer> dbCustomers,
+			LockMode lockMode)
+		{
+			return (from e in dbCustomers select e).SetLockMode(lockMode).WithOptions(o => o.SetTimeout(5));
+		}
+	}
 }
 
+