Merge pull request #254 from icsharpcode/raise-event

C# -> VB: Improve conversions to RaiseEvent

Author: GrahamTheCoder

CHANGELOG.md

@@ -1,7 +1,12 @@
 # Change Log
 All notable changes to the code converter will be documented here.
 
-# 6.5.0 TBC
+# 6.6.0 TBC
+
+### C# -> VB
+* Improve event identifier conversion
+
+# 6.5.0 03/03/2019
 * Avoid fatal error converting a project in a solution containing a website project (#243)
 * Improve best-effort conversion in the presence of errors
 * Improved nuget package and web converter's snippet detection

ICSharpCode.CodeConverter/Shared/ProjectConversion.cs

@@ -19,8 +19,6 @@ public class ProjectConversion
     {
         private readonly Compilation _sourceCompilation;
         private readonly IEnumerable<SyntaxTree> _syntaxTreesToConvert;
-        // ReSharper disable once StaticMemberInGenericType - Stateless
-        private static readonly AdhocWorkspace AdhocWorkspace = new AdhocWorkspace();
         private readonly ConcurrentDictionary<string, string> _errors = new ConcurrentDictionary<string, string>();
         private readonly Dictionary<string, SyntaxTree> _firstPassResults = new Dictionary<string, SyntaxTree>();
         private readonly ILanguageConversion _languageConversion;
@@ -147,12 +145,13 @@ private Dictionary<string, SyntaxNode> Convert()
         private Dictionary<string, SyntaxNode> SecondPass()
         {
             var secondPassByFilePath = new Dictionary<string, SyntaxNode>();
+            var adhocWorkspace = new AdhocWorkspace();
             foreach (var firstPassResult in _firstPassResults) {
                 var treeFilePath = firstPassResult.Key;
                 try {
-                    secondPassByFilePath.Add(treeFilePath, SingleSecondPass(firstPassResult));
+                    secondPassByFilePath.Add(treeFilePath, SingleSecondPass(firstPassResult, adhocWorkspace));
                 }  catch (Exception e) {
-                    secondPassByFilePath.Add(treeFilePath, Format(firstPassResult.Value.GetRoot()));
+                    secondPassByFilePath.Add(treeFilePath, Format(firstPassResult.Value.GetRoot(), adhocWorkspace));
                     _errors.TryAdd(treeFilePath, e.ToString());
                 }
             }
@@ -169,10 +168,10 @@ private void AddProjectWarnings()
             }
         }
 
-        private SyntaxNode SingleSecondPass(KeyValuePair<string, SyntaxTree> cs)
+        private SyntaxNode SingleSecondPass(KeyValuePair<string, SyntaxTree> cs, AdhocWorkspace workspace)
         {
             var secondPassNode = _languageConversion.SingleSecondPass(cs);
-            return Format(secondPassNode);
+            return Format(secondPassNode, workspace);
         }
 
         private void FirstPass()
@@ -237,10 +236,11 @@ private static async Task<SyntaxTree> GetSyntaxTreeWithAnnotatedSelection(Syntax
             return root.WithAnnotatedNode(selectedNode, AnnotationConstants.SelectedNodeAnnotationKind);
         }
 
-        private SyntaxNode Format(SyntaxNode resultNode)
+        private SyntaxNode Format(SyntaxNode resultNode, Workspace workspace)
         {
             SyntaxNode selectedNode = _handlePartialConversion ? GetSelectedNode(resultNode) : resultNode;
-            return Formatter.Format(selectedNode ?? resultNode, AdhocWorkspace);
+            SyntaxNode nodeToFormat = selectedNode ?? resultNode;
+            return Formatter.Format(nodeToFormat, workspace);
         }
 
         private SyntaxNode GetSelectedNode(SyntaxNode resultNode)

ICSharpCode.CodeConverter/VB/CommonConversions.cs

@@ -9,6 +9,7 @@
 using Microsoft.CodeAnalysis.VisualBasic;
 using Microsoft.CodeAnalysis.VisualBasic.Syntax;
 using AttributeListSyntax = Microsoft.CodeAnalysis.VisualBasic.Syntax.AttributeListSyntax;
+using BinaryExpressionSyntax = Microsoft.CodeAnalysis.CSharp.Syntax.BinaryExpressionSyntax;
 using CSharpExtensions = Microsoft.CodeAnalysis.CSharp.CSharpExtensions;
 using CSSyntaxKind = Microsoft.CodeAnalysis.CSharp.SyntaxKind;
 using ExpressionSyntax = Microsoft.CodeAnalysis.VisualBasic.Syntax.ExpressionSyntax;
@@ -206,7 +207,7 @@ public ExpressionSyntax ReduceArrayUpperBoundExpression(Microsoft.CodeAnalysis.C
 
         public LambdaExpressionSyntax ConvertLambdaExpression(AnonymousFunctionExpressionSyntax node, CSharpSyntaxNode body, IEnumerable<ParameterSyntax> parameters, SyntaxTokenList modifiers)
         {
-            var symbol = ModelExtensions.GetSymbolInfo(_semanticModel, node).Symbol as IMethodSymbol;
+            var symbol = (IMethodSymbol) ModelExtensions.GetSymbolInfo(_semanticModel, node).Symbol;
             var parameterList = SyntaxFactory.ParameterList(SyntaxFactory.SeparatedList(parameters.Select(p => (Microsoft.CodeAnalysis.VisualBasic.Syntax.ParameterSyntax)p.Accept(_nodesVisitor))));
             LambdaHeaderSyntax header;
             EndBlockStatementSyntax endBlock;
@@ -233,7 +234,8 @@ public LambdaExpressionSyntax ConvertLambdaExpression(AnonymousFunctionExpressio
                 var vbThrowExpression = (ExpressionSyntax)csThrowExpression.Expression.Accept(_nodesVisitor);
                 var vbThrowStatement = SyntaxFactory.ThrowStatement(SyntaxFactory.Token(SyntaxKind.ThrowKeyword), vbThrowExpression);
 
-                return SyntaxFactory.MultiLineFunctionLambdaExpression(header, SyntaxFactory.SingletonList<StatementSyntax>(vbThrowStatement), endBlock);
+                return SyntaxFactory.MultiLineFunctionLambdaExpression(header,
+                    SyntaxFactory.SingletonList<StatementSyntax>(vbThrowStatement), endBlock);
             } else {
                 statements = InsertRequiredDeclarations(
                     SyntaxFactory.SingletonList<StatementSyntax>(
@@ -396,19 +398,25 @@ public VisualBasicSyntaxNode ConvertTopLevelExpression(Microsoft.CodeAnalysis.CS
             return topLevelExpression.Accept(_nodesVisitor);
         }
 
-        private static ModifiedIdentifierSyntax ExtractIdentifier(Microsoft.CodeAnalysis.CSharp.Syntax.VariableDeclaratorSyntax v)
+        private ModifiedIdentifierSyntax ExtractIdentifier(Microsoft.CodeAnalysis.CSharp.Syntax.VariableDeclaratorSyntax v)
         {
             return SyntaxFactory.ModifiedIdentifier(ConvertIdentifier(v.Identifier));
         }
 
-        public static SyntaxToken ConvertIdentifier(SyntaxToken id)
+        public SyntaxToken ConvertIdentifier(SyntaxToken id)
         {
-            var idText = id.ValueText;
+            CSharpSyntaxNode parent = (CSharpSyntaxNode) id.Parent;
+            var idText = IsEventHandlerIdentifier(parent) && !IsEventHandlerAssignLhs(parent) ? id.ValueText + "Event" : id.ValueText;
             // Underscore is a special character in VB lexer which continues lines - not sure where to find the whole set of other similar tokens if any
             // Rather than a complicated contextual rename, just add an extra dash to all identifiers and hope this method is consistently used
+            bool keywordRequiresEscaping = KeywordRequiresEscaping(id);
+            return Identifier(idText, keywordRequiresEscaping);
+        }
+
+        public static SyntaxToken Identifier(string idText, bool keywordRequiresEscaping = false)
+        {
             if (idText.All(c => c == '_')) idText += "_";
-            
-            return KeywordRequiresEscaping(id) ? SyntaxFactory.Identifier($"[{idText}]") : SyntaxFactory.Identifier(idText);
+            return keywordRequiresEscaping ? SyntaxFactory.Identifier($"[{idText}]") : SyntaxFactory.Identifier(idText);
         }
 
         private static bool KeywordRequiresEscaping(SyntaxToken id)
@@ -530,5 +538,31 @@ private static string UppercaseFirstLetter(string sourceText)
         {
             return sourceText.Substring(0, 1).ToUpper() + sourceText.Substring(1);
         }
+
+        public bool IsEventHandlerIdentifier(CSharpSyntaxNode syntax)
+        {
+            return GetSymbol(syntax).IsKind(SymbolKind.Event);
+        }
+
+        private static bool IsEventHandlerAssignLhs(CSharpSyntaxNode syntax)
+        {
+            var assignmentExpressionSyntax = syntax.GetAncestor<AssignmentExpressionSyntax>();
+            return assignmentExpressionSyntax != null && assignmentExpressionSyntax.IsKind(CSSyntaxKind.AddAssignmentExpression, CSSyntaxKind.SubtractAssignmentExpression)
+                       && assignmentExpressionSyntax.Left.DescendantNodes().Contains(syntax);
+        }
+
+        private ISymbol GetSymbol(CSharpSyntaxNode syntax)
+        {
+            return syntax.SyntaxTree == _semanticModel.SyntaxTree
+                ? _semanticModel.GetSymbolInfo(syntax).Symbol
+                : null;
+        }
+
+        private ITypeSymbol GetTypeSymbol(CSharpSyntaxNode syntax)
+        {
+            return syntax.SyntaxTree == _semanticModel.SyntaxTree
+                ? _semanticModel.GetTypeInfo(syntax).Type
+                : null;
+        }
     }
 }