Test case adjustment: Supports connection strings set via connection.connection_string_name property (#517)

Author: AndrewShepherd

src/NHibernate.Test/NHSpecificTest/NH2420/Fixture.cs

@@ -2,12 +2,15 @@
 using System.Data;
 using System.Data.Odbc;
 using System.Data.SqlClient;
+using System.Configuration;
 using System.Transactions;
 using NHibernate.Dialect;
 using NHibernate.Driver;
 using NHibernate.Engine;
 using NUnit.Framework;
 
+using Environment = NHibernate.Cfg.Environment;
+
 namespace NHibernate.Test.NHSpecificTest.NH2420
 {
 	[TestFixture]
@@ -23,12 +26,35 @@ protected override bool AppliesTo(Dialect.Dialect dialect)
 			return (dialect is MsSql2005Dialect);
 		}
 
+		private string FetchConnectionStringFromConfiguration()
+		{
+			string connectionString;
+			if (cfg.Properties.TryGetValue(Environment.ConnectionString, out connectionString))
+			{
+				Assert.IsNotNullOrEmpty(connectionString);
+				return connectionString;
+			}
+			string connectionStringName;
+			if (cfg.Properties.TryGetValue(Environment.ConnectionStringName, out connectionStringName))
+			{
+				var connectionStringSettings = ConfigurationManager.ConnectionStrings[connectionStringName];
+				Assert.IsNotNull(connectionStringSettings);
+				connectionString = connectionStringSettings.ConnectionString;
+				Assert.IsNotNullOrEmpty(connectionString);
+				return connectionString;
+			}
+			else
+			{
+				Assert.Fail("Unable to find a connection string or connection string name");
+				return string.Empty;
+			}
+		}
+
 		[Test]
 		public void ShouldBeAbleToReleaseSuppliedConnectionAfterDistributedTransaction()
 		{
-			string connectionString = cfg.GetProperty("connection.connection_string");
+			string connectionString = FetchConnectionStringFromConfiguration();
 			ISession s;
-
 			using (var ts = new TransactionScope())
 			{
 				// Enlisting DummyEnlistment as a durable resource manager will start