Reuse SchemaExport in tests

Author: bahusoid

src/NHibernate.Test/Async/NHSpecificTest/NH1635/Fixture.cs

@@ -62,7 +62,7 @@ protected override bool AppliesTo(Dialect.Dialect dialect)
 		protected override void CreateSchema()
 		{
 			var script = new StringBuilder();
-			new SchemaExport(cfg).Create(sl=> script.Append(sl) , true);
+			SchemaExport.Create(sl => script.Append(sl), true);
 			Assert.That(script.ToString(), Does.Not.Contain("LatestMessage"));
 		}
 

src/NHibernate.Test/Async/NHSpecificTest/NH1939/Fixture.cs

@@ -40,7 +40,7 @@ public async Task Can_Parameterise_Auxiliary_Database_ObjectsAsync()
 		{
 			schemaBuilder = new StringBuilder();
 
-			SchemaExport schemaExport = new SchemaExport(cfg);
+			SchemaExport schemaExport = SchemaExport;
 			await (schemaExport.ExecuteAsync(AddString, false, false));
 
 			string schema = schemaBuilder.ToString();

src/NHibernate.Test/NHSpecificTest/NH1635/Fixture.cs

@@ -50,7 +50,7 @@ private void CleanUp()
 		protected override void CreateSchema()
 		{
 			var script = new StringBuilder();
-			new SchemaExport(cfg).Create(sl=> script.Append(sl) , true);
+			SchemaExport.Create(sl => script.Append(sl), true);
 			Assert.That(script.ToString(), Does.Not.Contain("LatestMessage"));
 		}
 

src/NHibernate.Test/NHSpecificTest/NH1939/Fixture.cs

@@ -29,7 +29,7 @@ public void Can_Parameterise_Auxiliary_Database_Objects()
 		{
 			schemaBuilder = new StringBuilder();
 
-			SchemaExport schemaExport = new SchemaExport(cfg);
+			SchemaExport schemaExport = SchemaExport;
 			schemaExport.Execute(AddString, false, false);
 
 			string schema = schemaBuilder.ToString();

src/NHibernate.Test/TestCase.cs

@@ -22,6 +22,7 @@ public abstract class TestCase
 		private const bool OutputDdl = false;
 		protected Configuration cfg;
 		private DebugSessionFactory _sessionFactory;
+		private SchemaExport _schemaExport;
 
 		private static readonly ILog log = LogManager.GetLogger(typeof(TestCase));
 
@@ -48,6 +49,8 @@ protected virtual string MappingsAssembly
 			get { return "NHibernate.DomainModel"; }
 		}
 
+		protected SchemaExport SchemaExport => _schemaExport ?? (_schemaExport = new SchemaExport(cfg));
+
 		static TestCase()
 		{
 			// Configure log4net here since configuration through an attribute doesn't always work.
@@ -281,12 +284,12 @@ protected virtual void AddMappings(Configuration configuration)
 
 		protected virtual void CreateSchema()
 		{
-			new SchemaExport(cfg).Create(OutputDdl, true);
+			SchemaExport.Create(OutputDdl, true);
 		}
 
 		protected virtual void DropSchema()
 		{
-			DropSchema(OutputDdl, new SchemaExport(cfg), Sfi);
+			DropSchema(OutputDdl, SchemaExport, Sfi);
 		}
 
 		public static void DropSchema(bool useStdOut, SchemaExport export, ISessionFactoryImplementor sfi)
@@ -315,6 +318,7 @@ private void Cleanup()
 			Sfi?.Close();
 			_sessionFactory = null;
 			cfg = null;
+			_schemaExport = null;
 		}
 
 		public int ExecuteStatement(string sql)