Add support for extract method in the PrimaryConstructor base list (#76371)

Author: CyrusNajmabadi

src/Features/CSharp/Portable/ExtractMethod/CSharpMethodExtractor.Analyzer.cs

@@ -25,6 +25,9 @@ public static AnalyzerResult Analyze(CSharpSelectionResult selectionResult, bool
         protected override bool TreatOutAsRef
             => false;
 
+        protected override bool IsInPrimaryConstructorBaseType()
+            => this.SelectionResult.GetContainingScopeOf<PrimaryConstructorBaseTypeSyntax>() != null;
+
         protected override VariableInfo CreateFromSymbol(
             Compilation compilation,
             ISymbol symbol,

src/Features/CSharp/Portable/ExtractMethod/CSharpMethodExtractor.CSharpCodeGenerator.CallSiteContainerRewriter.cs

@@ -426,6 +426,15 @@ public override SyntaxNode VisitCompilationUnit(CompilationUnitSyntax node)
                 return node.WithMembers(newMembers);
             }
 
+            public override SyntaxNode VisitBaseList(BaseListSyntax node)
+            {
+                if (node != ContainerOfStatementsOrFieldToReplace)
+                    return base.VisitBaseList(node);
+
+                var primaryConstructorBase = (PrimaryConstructorBaseTypeSyntax)_statementsOrMemberOrAccessorToInsert.Single();
+                return node.WithTypes(node.Types.Replace(node.Types[0], primaryConstructorBase));
+            }
+
             private SyntaxNode GetUpdatedTypeDeclaration(TypeDeclarationSyntax node)
             {
                 var newMembers = VisitList(ReplaceMembers(node.Members, global: false));

src/Features/CSharp/Portable/ExtractMethod/CSharpMethodExtractor.CSharpCodeGenerator.ExpressionCodeGenerator.cs

@@ -136,7 +136,9 @@ protected override SyntaxNode GetFirstStatementOrInitializerSelectedAtCallSite()
 
                 // This is similar to FieldDeclaration case but we only want to do this 
                 // if the member has an expression body.
-                scope ??= this.SelectionResult.GetContainingScopeOf<ArrowExpressionClauseSyntax>().Parent;
+                scope ??= this.SelectionResult.GetContainingScopeOf<ArrowExpressionClauseSyntax>()?.Parent;
+
+                scope ??= this.SelectionResult.GetContainingScopeOf<PrimaryConstructorBaseTypeSyntax>();
 
                 return scope;
             }

src/Features/CSharp/Portable/ExtractMethod/CSharpMethodExtractor.CSharpCodeGenerator.cs

@@ -146,7 +146,7 @@ private async Task<ImmutableArray<SyntaxNode>> CreateStatementsOrInitializerToIn
             var selectedNode = GetFirstStatementOrInitializerSelectedAtCallSite();
 
             // field initializer, constructor initializer, expression bodied member case
-            if (selectedNode is ConstructorInitializerSyntax or FieldDeclarationSyntax ||
+            if (selectedNode is ConstructorInitializerSyntax or FieldDeclarationSyntax or PrimaryConstructorBaseTypeSyntax ||
                 IsExpressionBodiedMember(selectedNode) ||
                 IsExpressionBodiedAccessor(selectedNode))
             {

src/Features/CSharp/Portable/ExtractMethod/CSharpMethodExtractor.cs

@@ -113,6 +113,10 @@ protected override SyntaxNode GetInsertionPointNode(
         else
         {
             var baseToken = root.FindToken(originalSpanStart);
+            var primaryConstructorBaseType = baseToken.GetAncestor<PrimaryConstructorBaseTypeSyntax>();
+            if (primaryConstructorBaseType != null)
+                return primaryConstructorBaseType;
+
             var memberNode = baseToken.GetAncestor<MemberDeclarationSyntax>();
             Contract.ThrowIfNull(memberNode);
             Contract.ThrowIfTrue(memberNode.Kind() == SyntaxKind.NamespaceDeclaration);

src/Features/CSharp/Portable/ExtractMethod/CSharpSelectionResult.cs

@@ -109,10 +109,9 @@ public override SyntaxNode GetOutermostCallSiteContainerToProcess(CancellationTo
             var container = this.GetInnermostStatementContainer();
 
             Contract.ThrowIfNull(container);
-            Contract.ThrowIfFalse(container.IsStatementContainerNode() ||
-                                  container is TypeDeclarationSyntax ||
-                                  container is ConstructorDeclarationSyntax ||
-                                  container is CompilationUnitSyntax);
+            Contract.ThrowIfFalse(
+                container.IsStatementContainerNode() ||
+                container is BaseListSyntax or TypeDeclarationSyntax or ConstructorDeclarationSyntax or CompilationUnitSyntax);
 
             return container;
         }
@@ -171,9 +170,7 @@ public SyntaxNode GetInnermostStatementContainer()
         foreach (var statement in statements)
         {
             if (statement.IsStatementContainerNode())
-            {
                 return statement;
-            }
 
             last = statement;
         }
@@ -190,16 +187,16 @@ public SyntaxNode GetInnermostStatementContainer()
         // constructor initializer case
         var constructorInitializer = GetContainingScopeOf<ConstructorInitializerSyntax>();
         if (constructorInitializer != null)
-        {
             return constructorInitializer.Parent;
-        }
 
         // field initializer case
         var field = GetContainingScopeOf<FieldDeclarationSyntax>();
         if (field != null)
-        {
             return field.Parent;
-        }
+
+        var primaryConstructorBaseType = GetContainingScopeOf<PrimaryConstructorBaseTypeSyntax>();
+        if (primaryConstructorBaseType != null)
+            return primaryConstructorBaseType.Parent;
 
         Contract.ThrowIfFalse(last.IsParentKind(SyntaxKind.GlobalStatement));
         Contract.ThrowIfFalse(last.Parent.IsParentKind(SyntaxKind.CompilationUnit));

src/Features/CSharp/Portable/ExtractMethod/CSharpSelectionValidator.cs

@@ -273,8 +273,10 @@ private static bool CheckTopLevel(SyntaxNode node, TextSpan span)
         {
             case BlockSyntax block:
                 return ContainsInBlockBody(block, span);
+
             case ArrowExpressionClauseSyntax expressionBodiedMember:
                 return ContainsInExpressionBodiedMemberBody(expressionBodiedMember, span);
+
             case FieldDeclarationSyntax field:
                 {
                     foreach (var variable in field.Declaration.Variables)
@@ -290,8 +292,12 @@ private static bool CheckTopLevel(SyntaxNode node, TextSpan span)
 
             case GlobalStatementSyntax:
                 return true;
+
             case ConstructorInitializerSyntax constructorInitializer:
                 return constructorInitializer.ContainsInArgument(span);
+
+            case PrimaryConstructorBaseTypeSyntax primaryConstructorBaseType:
+                return primaryConstructorBaseType.ArgumentList.Arguments.FullSpan.Contains(span);
         }
 
         return false;