Converts "default" keyword to "Nothing" keyword - fixes #428

CHANGELOG.md

@@ -41,6 +41,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ### C# -> VB
 
+* Converts "default" keyword to "Nothing" keyword [#428](https://github.com/icsharpcode/CodeConverter/issues/428)
 
 ## [7.9.0] - 2020-02-27
 

CodeConverter/VB/NodesVisitor.cs

@@ -820,8 +820,10 @@ public override VisualBasicSyntaxNode VisitParameter(CSS.ParameterSyntax node)
 
         public override VisualBasicSyntaxNode VisitLiteralExpression(CSS.LiteralExpressionSyntax node)
         {
-            // now this looks somehow hacky... is there a better way?
-            if (node.IsKind(CS.SyntaxKind.StringLiteralExpression) && node.Token.Text.StartsWith("@", StringComparison.Ordinal)) {
+            if (node.IsKind(CS.SyntaxKind.DefaultLiteralExpression)) {
+                return VisualBasicSyntaxFactory.NothingExpression;
+                // This looks somehow hacky... is there a better way to check whether it's a verbatim string?
+            } else if (node.IsKind(CS.SyntaxKind.StringLiteralExpression) && node.Token.Text.StartsWith("@", StringComparison.Ordinal)) {
                 return SyntaxFactory.StringLiteralExpression(
                     SyntaxFactory.StringLiteralToken(
                         node.Token.Text.Substring(1),

Tests/VB/ExpressionTests.cs

@@ -80,6 +80,30 @@ End Sub
 End Class");
         }
 
+        [Fact]
+        public async Task DefaultLiteralExpression()
+        {
+            await TestConversionCSharpToVisualBasic(@"public class DefaultLiteralExpression {
+
+    public bool Foo {
+        get {
+	        return (Bar == default);
+        }
+    }
+
+    public int Bar;
+
+}", @"Public Class DefaultLiteralExpression
+    Public ReadOnly Property Foo As Boolean
+        Get
+            Return Bar = Nothing
+        End Get
+    End Property
+
+    Public Bar As Integer
+End Class");
+        }
+
         [Fact]
         public async Task IsNullExpression()
         {