Disable Use Object Initializer diagnostic prior to C# 3

src/EditorFeatures/CSharpTest/UseObjectInitializer/UseObjectInitializerTests.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.CodeFixes;
+using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.UseObjectInitializer;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.Diagnostics;
@@ -193,6 +194,23 @@ void M()
 }");
         }
 
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseObjectInitializer)]
+        public async Task TestMissingBeforeCSharp3()
+        {
+            await TestMissingAsync(
+@"
+class C
+{
+    int i;
+    int j;
+    void M()
+    {
+        var c = [||]new C();
+        c.j = 1;
+    }
+}", parseOptions: CSharpParseOptions.Default.WithLanguageVersion(LanguageVersion.CSharp2));
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsUseObjectInitializer)]
         public async Task TestFixAllInDocument()
         {

src/Features/CSharp/Portable/UseObjectInitializer/CSharpUseObjectInitializerDiagnosticAnalyzer.cs

@@ -21,6 +21,13 @@ internal class CSharpUseObjectInitializerDiagnosticAnalyzer :
     {
         protected override bool FadeOutOperatorToken => true;
 
+        protected override bool AreObjectInitializersSupported(SyntaxNodeAnalysisContext context)
+        {
+            // object initializers are only available in C# 3.0 and above.  Don't offer this refactoring
+            // in projects targeting a lesser version.
+            return ((CSharpParseOptions)context.Node.SyntaxTree.Options).LanguageVersion >= LanguageVersion.CSharp3;
+        }
+
         protected override SyntaxKind GetObjectCreationSyntaxKind() => SyntaxKind.ObjectCreationExpression;
 
         protected override ISyntaxFactsService GetSyntaxFactsService() => CSharpSyntaxFactsService.Instance;

src/Features/Core/Portable/UseObjectInitializer/AbstractUseObjectInitializerDiagnosticAnalyzer.cs

@@ -44,8 +44,15 @@ public override void Initialize(AnalysisContext context)
 
         protected abstract TSyntaxKind GetObjectCreationSyntaxKind();
 
+        protected abstract bool AreObjectInitializersSupported(SyntaxNodeAnalysisContext context);
+
         private void AnalyzeNode(SyntaxNodeAnalysisContext context)
         {
+            if (!AreObjectInitializersSupported(context))
+            {
+                return;
+            }
+
             var objectCreationExpression = (TObjectCreationExpressionSyntax)context.Node;
             var language = objectCreationExpression.Language;
 

src/Features/VisualBasic/Portable/UseObjectInitializer/VisualBasicUseObjectInitializerDiagnosticAnalyzer.vb

@@ -23,6 +23,11 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.UseObjectInitializer
             End Get
         End Property
 
+        Protected Overrides Function AreObjectInitializersSupported(context As SyntaxNodeAnalysisContext) As Boolean
+            'Object Initializers are supported in all the versions of Visual Basic we support
+            Return True
+        End Function
+
         Protected Overrides Function GetObjectCreationSyntaxKind() As SyntaxKind
             Return SyntaxKind.ObjectCreationExpression
         End Function