fix conversion of anonymous delegate-Expressions to VB lambdas

src/Libraries/NRefactory/Project/Src/PrettyPrinter/VBNet/VBNetOutputVisitor.cs

@@ -2512,7 +2512,7 @@ namespace ICSharpCode.NRefactory.PrettyPrinter
 		
 		public override object TrackedVisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression, object data)
 		{
-			OutputAnonymousMethodWithStatementBody(anonymousMethodExpression.Parameters, anonymousMethodExpression.Body);
+			UnsupportedNode(anonymousMethodExpression);
 			return null;
 		}
 		
@@ -2988,30 +2988,6 @@ namespace ICSharpCode.NRefactory.PrettyPrinter
 			}
 		}
 		
-		void OutputAnonymousMethodWithStatementBody(List<ParameterDeclarationExpression> parameters, Statement body)
-		{
-			Error("VB does not support anonymous methods/lambda expressions with a statement body", body.StartLocation);
-			
-			outputFormatter.PrintToken(Tokens.Function);
-			outputFormatter.PrintToken(Tokens.OpenParenthesis);
-			AppendCommaSeparatedList(parameters);
-			outputFormatter.PrintToken(Tokens.CloseParenthesis);
-			outputFormatter.Space();
-			outputFormatter.PrintToken(Tokens.Do);
-			outputFormatter.NewLine();
-			
-			++outputFormatter.IndentationLevel;
-			exitTokenStack.Push(Tokens.Function);
-			body.AcceptVisitor(this, null);
-			exitTokenStack.Pop();
-			--outputFormatter.IndentationLevel;
-			
-			outputFormatter.Indent();
-			outputFormatter.PrintToken(Tokens.End);
-			outputFormatter.Space();
-			outputFormatter.PrintToken(Tokens.Function);
-		}
-		
 		public override object TrackedVisitQueryExpressionVB(QueryExpressionVB queryExpression, object data)
 		{
 			outputFormatter.IndentationLevel++;

src/Libraries/NRefactory/Project/Src/Visitors/ToVBNetConvertVisitor.cs

@@ -19,7 +19,7 @@ namespace ICSharpCode.NRefactory.Visitors
 		// The following conversions are implemented:
 		//   Conflicting field/property names -> m_field
 		//   Conflicting variable names inside methods
-		//   Anonymous methods are put into new methods
+		//   Anonymous methods are converted to Sub/Function-lambdas
 		//   Simple event handler creation is replaced with AddressOfExpression
 		//   Move Imports-statements out of namespaces
 		//   Parenthesis around Cast expressions remove - these are syntax errors in VB.NET
@@ -134,17 +134,47 @@ namespace ICSharpCode.NRefactory.Visitors
 		public override object VisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression, object data)
 		{
 			base.VisitAnonymousMethodExpression(anonymousMethodExpression, data);
+			LambdaExpression lambda = new LambdaExpression();
+			lambda.Parameters = anonymousMethodExpression.Parameters;
 			if (anonymousMethodExpression.Body.Children.Count == 1) {
 				ReturnStatement rs = anonymousMethodExpression.Body.Children[0] as ReturnStatement;
-				if (rs != null) {
+				if (rs != null)
-					LambdaExpression lambda = new LambdaExpression();
 					lambda.ExpressionBody = rs.Expression;
-					lambda.Parameters = anonymousMethodExpression.Parameters;
+				else {
+					lambda.StatementBody = anonymousMethodExpression.Body.Children[0] as Statement;
+					lambda.ReturnType = new TypeReference("System.Void", true);
+				}
+			} else {
+				var visitor = new ReturnStatementVisitor();
+				anonymousMethodExpression.AcceptVisitor(visitor, null);
+				lambda.StatementBody = anonymousMethodExpression.Body;
+				if (!visitor.HasReturn)
+					lambda.ReturnType = new TypeReference("System.Void", true);
+			}
 			ReplaceCurrentNode(lambda);
+			return null;
+		}
+		
+		sealed class ReturnStatementVisitor : AbstractAstVisitor
+		{
+			public bool HasReturn { get; private set; }
+			
+			public override object VisitReturnStatement(ReturnStatement returnStatement, object data)
+			{
+				HasReturn = true;
+				return base.VisitReturnStatement(returnStatement, data);
 			}
+			
+			public override object VisitLambdaExpression(LambdaExpression lambdaExpression, object data)
+			{
+				return null;
 			}
+			
+			public override object VisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression, object data)
+			{
 				return null;
 			}
+		}
 		
 		public override object VisitAssignmentExpression(AssignmentExpression assignmentExpression, object data)
 		{