Update SA1113 for target-typed new

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers.Test.CSharp9/ReadabilityRules/SA1113CSharp9UnitTests.cs

@@ -3,9 +3,58 @@
 
 namespace StyleCop.Analyzers.Test.CSharp9.ReadabilityRules
 {
+    using System.Threading;
+    using System.Threading.Tasks;
+    using Microsoft.CodeAnalysis.Testing;
     using StyleCop.Analyzers.Test.CSharp8.ReadabilityRules;
+    using StyleCop.Analyzers.Test.Helpers;
+    using Xunit;
+    using static StyleCop.Analyzers.Test.Verifiers.StyleCopCodeFixVerifier<
+        StyleCop.Analyzers.ReadabilityRules.SA1113CommaMustBeOnSameLineAsPreviousParameter,
+        StyleCop.Analyzers.SpacingRules.TokenSpacingCodeFixProvider>;
 
     public partial class SA1113CSharp9UnitTests : SA1113CSharp8UnitTests
     {
+        [Fact]
+        [WorkItem(3972, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/3972")]
+        public async Task TestTargetTypedNewCommaPlacementAsync()
+        {
+            var testCode = @"
+class TestClass
+{
+    public TestClass(int first, int second)
+    {
+    }
+}
+
+class Test
+{
+    void M()
+    {
+        TestClass value = new(1
+            {|#0:,|} 2);
+    }
+}";
+
+            var fixedCode = @"
+class TestClass
+{
+    public TestClass(int first, int second)
+    {
+    }
+}
+
+class Test
+{
+    void M()
+    {
+        TestClass value = new(1,
+            2);
+    }
+}";
+
+            var expected = Diagnostic().WithLocation(0);
+            await VerifyCSharpFixAsync(testCode, expected, fixedCode, CancellationToken.None).ConfigureAwait(false);
+        }
     }
 }

StyleCop.Analyzers/StyleCop.Analyzers/ReadabilityRules/SA1113CommaMustBeOnSameLineAsPreviousParameter.cs

@@ -63,6 +63,7 @@ internal class SA1113CommaMustBeOnSameLineAsPreviousParameter : DiagnosticAnalyz
         private static readonly Action<SyntaxNodeAnalysisContext> LocalFunctionStatementAction = HandleLocalFunctionStatement;
         private static readonly Action<SyntaxNodeAnalysisContext> InvocationExpressionAction = HandleInvocationExpression;
         private static readonly Action<SyntaxNodeAnalysisContext> ObjectCreationExpressionAction = HandleObjectCreationExpression;
+        private static readonly Action<SyntaxNodeAnalysisContext> ImplicitObjectCreationExpressionAction = HandleImplicitObjectCreationExpression;
         private static readonly Action<SyntaxNodeAnalysisContext> IndexerDeclarationAction = HandleIndexerDeclaration;
         private static readonly Action<SyntaxNodeAnalysisContext> ElementAccessExpressionAction = HandleElementAccessExpression;
         private static readonly Action<SyntaxNodeAnalysisContext> AnonymousMethodExpressionAction = HandleAnonymousMethodExpression;
@@ -87,6 +88,7 @@ public override void Initialize(AnalysisContext context)
             context.RegisterSyntaxNodeAction(LocalFunctionStatementAction, SyntaxKindEx.LocalFunctionStatement);
             context.RegisterSyntaxNodeAction(InvocationExpressionAction, SyntaxKind.InvocationExpression);
             context.RegisterSyntaxNodeAction(ObjectCreationExpressionAction, SyntaxKind.ObjectCreationExpression);
+            context.RegisterSyntaxNodeAction(ImplicitObjectCreationExpressionAction, SyntaxKindEx.ImplicitObjectCreationExpression);
             context.RegisterSyntaxNodeAction(IndexerDeclarationAction, SyntaxKind.IndexerDeclaration);
             context.RegisterSyntaxNodeAction(ElementAccessExpressionAction, SyntaxKind.ElementAccessExpression);
             context.RegisterSyntaxNodeAction(AnonymousMethodExpressionAction, SyntaxKind.AnonymousMethodExpression);
@@ -187,6 +189,12 @@ private static void HandleObjectCreationExpression(SyntaxNodeAnalysisContext con
             HandleBaseArgumentListSyntax(context, objectCreationExpression.ArgumentList);
         }
 
+        private static void HandleImplicitObjectCreationExpression(SyntaxNodeAnalysisContext context)
+        {
+            var implicitObjectCreation = (ImplicitObjectCreationExpressionSyntaxWrapper)context.Node;
+            HandleBaseArgumentListSyntax(context, implicitObjectCreation.ArgumentList);
+        }
+
         private static void HandleInvocationExpression(SyntaxNodeAnalysisContext context)
         {
             var invocationEpression = (InvocationExpressionSyntax)context.Node;

documentation/SA1113.md

@@ -23,6 +23,8 @@ A comma between two parameters in a call to a C# method or indexer, or in the de
 
 A violation of this rule occurs when a comma between two parameters to a method or indexer is not placed on the same line as the previous parameter. The following examples show correct placement of the comma:
 
+The same guidance applies to constructor invocations and object creation expressions, including target-typed `new` introduced in C# 9. Commas separating arguments to `new(...)` must appear on the same line as the preceding argument.
+
 ```csharp
 public string JoinName(string first, string last)
 {