NH-4026 - Firebird locks table till connection are actually closed, not only returned to pool. Clearing the pool as a solution.

Author: fredericDelaporte

src/NHibernate.Test/NHSpecificTest/NH1908ThreadSafety/Fixture.cs

@@ -2,7 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
-using NHibernate.Util;
+using NHibernate.Dialect;
 using NUnit.Framework;
 
 namespace NHibernate.Test.NHSpecificTest.NH1908ThreadSafety
@@ -12,29 +12,12 @@ public class Fixture : BugTestCase
 	{
 		protected override bool AppliesTo(Dialect.Dialect dialect)
 		{
-			return !(dialect is Dialect.Oracle8iDialect);
+			return !(dialect is Oracle8iDialect);
 			// Oracle sometimes causes: ORA-12520: TNS:listener could not find available handler for requested type of server
 			// Following links bizarrely suggest it's an Oracle limitation under load:
 			// http://www.orafaq.com/forum/t/60019/2/ & http://www.ispirer.com/wiki/sqlways/troubleshooting-guide/oracle/import/tns_listener
 		}
 
-		protected override void OnTearDown()
-		{
-			base.OnTearDown();
-
-			if (!(Dialect is Dialect.FirebirdDialect))
-				return;
-
-			// Firebird will pool each connection created during the test and will not drop the created tables
-			// which will result in other tests failing when they try to create tables with same name
-			// By clearing the connection pool the tables will get dropped. This is done by the following code.
-			var fbConnectionType = ReflectHelper.TypeFromAssembly("FirebirdSql.Data.FirebirdClient.FbConnection", "FirebirdSql.Data.FirebirdClient", false);
-			var clearPool = fbConnectionType.GetMethod("ClearPool");
-			var sillyConnection = Sfi.ConnectionProvider.GetConnection();
-			clearPool.Invoke(null, new object[] { sillyConnection });
-			Sfi.ConnectionProvider.CloseConnection(sillyConnection);
-		}
-
 		[Test]
 		public void UsingFiltersIsThreadSafe()
 		{

src/NHibernate.Test/TestCase.cs

@@ -14,6 +14,8 @@
 using NHibernate.Hql.Ast.ANTLR;
 using NUnit.Framework.Interfaces;
 using System.Text;
+using NHibernate.Dialect;
+using NHibernate.Util;
 
 namespace NHibernate.Test
 {
@@ -269,6 +271,27 @@ protected virtual void CreateSchema()
 
 		protected virtual void DropSchema()
 		{
+			if (Dialect is FirebirdDialect)
+			{
+				// Firebird will pool each connection created during the test and will marked as used any table
+				// referenced by queries. It will at best delays those tables drop until connections are actually
+				// closed, or immediately fail dropping them.
+				// This results in other tests failing when they try to create tables with same name.
+				// By clearing the connection pool the tables will get dropped. This is done by the following code.
+				// Moved from NH1908 test case, contributed by Amro El-Fakharany.
+				var clearConnection = Sfi.ConnectionProvider.GetConnection();
+				try
+				{
+					var fbConnectionType = clearConnection.GetType();
+					var clearPool = fbConnectionType.GetMethod("ClearPool");
+					clearPool.Invoke(null, new object[] {clearConnection});
+				}
+				finally
+				{
+					Sfi.ConnectionProvider.CloseConnection(clearConnection);
+				}
+			}
+
 			new SchemaExport(cfg).Drop(OutputDdl, true);
 		}