Less eagerly extract local function

Author: GrahamTheCoder

CodeConverter/CSharp/ExpressionNodeVisitor.cs

@@ -5,6 +5,7 @@
 using ICSharpCode.CodeConverter.Shared;
 using ICSharpCode.CodeConverter.Util;
 using ICSharpCode.CodeConverter.Util.FromRoslyn;
+using ICSharpCode.CodeConverter.VB;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
@@ -827,7 +828,7 @@ public override async Task<CSharpSyntaxNode> VisitInvocationExpression(
                 if (withinLocalFunction) {
                     return await HoistAndCallLocalFunction(node, invocationSymbol, (ExpressionSyntax)convertedInvocation);
                 }
-                return await ConvertInvocation(node, invocationSymbol);
+                return convertedInvocation;
             } finally {
                 if (withinLocalFunction) {
                     _additionalLocals.PopExpressionScope();
@@ -956,9 +957,20 @@ private static bool IsDefinitelyExecutedInStatement(VBSyntax.InvocationExpressio
             do {
                 parentStatement = parentStatement.GetAncestor<VBSyntax.StatementSyntax>();
             } while (parentStatement is VBSyntax.ElseIfStatementSyntax);
-            return parentStatement.FollowProperty(n => n.ChildNodes().FirstOrDefault()).Contains(invocation);
+            return parentStatement.FollowProperty(n => GetLeftMostWithPossibleExitPoints(n)).Contains(invocation);
         }
 
+        /// <summary>
+        /// It'd be great to use _semanticModel.AnalyzeControlFlow(invocation).ExitPoints, but that doesn't account for the possibility of exceptions
+        /// </summary>
+        /// <param name="n"></param>
+        /// <returns></returns>
+        private static SyntaxNode GetLeftMostWithPossibleExitPoints(SyntaxNode n) => n switch
+        {
+            VBSyntax.VariableDeclaratorSyntax vds => vds.Initializer,
+            _ => n.ChildNodes().FirstOrDefault()
+        };
+
         public override async Task<CSharpSyntaxNode> VisitSingleLineLambdaExpression(VBasic.Syntax.SingleLineLambdaExpressionSyntax node)
         {
             IReadOnlyCollection<StatementSyntax> convertedStatements;

Tests/CSharp/ExpressionTests/ByRefTests.cs

@@ -353,7 +353,7 @@ Public Sub UsesRef(someBool As Boolean, someInt As Integer)
         TakesRefVoid(1) 'Requires variable before
         TakesRefVoid(Prop2) ' Requires variable before, and to assign back after
                 
-        Dim a =TakesRef(someInt) ' Convert directly
+        Dim a = TakesRef(someInt) ' Convert directly
         Dim b = TakesRef(2) 'Requires variable before
         Dim c = TakesRef(Prop) ' Requires variable before, and to assign back after
 
@@ -366,7 +366,8 @@ Else If TakesRef(Prop) ' Requires variable before, and to assign back after (in
         End If
         Console.WriteLine(someInt)
     End Sub
-End Class", @"
+End Class", @"using System;
+
 public partial class MyTestClass
 {
     private int Prop { get; set; }
@@ -389,25 +390,18 @@ public void UsesRef(bool someBool, int someInt)
         int argvrbTst = 1;
         TakesRefVoid(ref argvrbTst); // Requires variable before
         int argvrbTst1 = Prop2;
-        TakesRefVoid(ref argvrbTst1); // Requires variable before, and to assign back after
+        TakesRefVoid(ref argvrbTst1);
+        Prop2 = argvrbTst1; // Requires variable before, and to assign back after
         bool a = TakesRef(ref someInt); // Convert directly
         int argvrbTst2 = 2;
         bool b = TakesRef(ref argvrbTst2); // Requires variable before
         int argvrbTst3 = Prop;
-        bool c = TakesRef(ref argvrbTst3); // Requires variable before, and to assign back after
+        bool c = TakesRef(ref argvrbTst3);
+        Prop = argvrbTst3; // Requires variable before, and to assign back after
+        bool localTakesRef1() { int argvrbTst = Prop; var ret = TakesRef(ref argvrbTst); Prop = argvrbTst; return ret; }
+
+        bool localTakesRef2() { int argvrbTst = 3; var ret = TakesRef(ref argvrbTst); return ret; }
 
-        bool localTakesRef1() {
-            int argvrbTst4 = 3;
-            var ret = TakesRef(ref argvrbTst4);
-            return ret;
-        }
-        bool localTakesRef2() {
-            int argvrbTst5 = Prop;
-            var ret = TakesRef(ref argvrbTst5);
-            Prop = argvrbTst5;
-            return ret;
-        }
-            
         if (16 > someInt || TakesRef(ref someInt)) // Convert directly
         {
             Console.WriteLine(1);