Do not offer to convert typeof to nameof on a generic type

src/Analyzers/CSharp/Analyzers/ConvertTypeofToNameof/CSharpConvertTypeOfToNameOfDiagnosticAnalyzer.cs

@@ -19,9 +19,6 @@ internal sealed class CSharpConvertTypeOfToNameOfDiagnosticAnalyzer()
 {
     private static readonly string s_title = CSharpAnalyzersResources.typeof_can_be_converted_to_nameof;
 
-    protected override bool SupportsUnboundGenerics(ParseOptions options)
-        => options.LanguageVersion().IsCSharp14OrAbove();
-
     protected override bool IsValidTypeofAction(OperationAnalysisContext context)
     {
         var node = context.Operation.Syntax;

src/Analyzers/CSharp/Tests/ConvertTypeOfToNameOf/ConvertTypeOfToNameOfTests.cs

@@ -267,19 +267,7 @@ class Goo<T>
                     { 
                         void M() 
                         {
-                            _ = [|typeof(Goo<int>).Name|];
-                        }
-                    }
-                }
-                """,
-            FixedCode = """
-                class Test
-                {
-                    class Goo<T> 
-                    { 
-                        void M() 
-                        {
-                            _ = nameof(Goo<>);
+                            _ = typeof(Goo<int>).Name;
                         }
                     }
                 }
@@ -321,19 +309,7 @@ class Goo<T>
                     { 
                         void M() 
                         {
-                            _ = [|typeof(Goo<>).Name|];
-                        }
-                    }
-                }
-                """,
-            FixedCode = """
-                class Test
-                {
-                    class Goo<T> 
-                    { 
-                        void M() 
-                        {
-                            _ = nameof(Goo<>);
+                            _ = typeof(Goo<>).Name;
                         }
                     }
                 }

src/Analyzers/Core/Analyzers/ConvertTypeofToNameof/AbstractConvertTypeOfToNameOfDiagnosticAnalyzer.cs

@@ -20,12 +20,8 @@ public override DiagnosticAnalyzerCategory GetAnalyzerCategory()
 
     protected abstract bool IsValidTypeofAction(OperationAnalysisContext context);
 
-    protected abstract bool SupportsUnboundGenerics(ParseOptions options);
-
     protected override void InitializeWorker(AnalysisContext context)
-    {
-        context.RegisterOperationAction(AnalyzeAction, OperationKind.TypeOf);
-    }
+        => context.RegisterOperationAction(AnalyzeAction, OperationKind.TypeOf);
 
     protected void AnalyzeAction(OperationAnalysisContext context)
     {
@@ -47,7 +43,7 @@ protected void AnalyzeAction(OperationAnalysisContext context)
 
     }
 
-    private bool IsValidOperation(IOperation operation)
+    private static bool IsValidOperation(IOperation operation)
     {
         // Cast to a typeof operation & check parent is a property reference and member access
         var typeofOperation = (ITypeOfOperation)operation;
@@ -69,11 +65,10 @@ private bool IsValidOperation(IOperation operation)
         if (typeofOperation.TypeOperand is not INamedTypeSymbol namedType)
             return false;
 
-        // Non-generic types are always convertible.  typeof(X).Name can always be converted to nameof(X)
-        if (namedType.TypeArguments.Length == 0)
-            return true;
-
-        // Generic types are convertible if the lang supports it.  e.g. typeof(X<Y>).Name can be converted to nameof(X<>).
-        return SupportsUnboundGenerics(operation.Syntax.SyntaxTree.Options);
+        // Note: generic names like `typeof(List<int>)` are not convertible (since the name will be List`1). However,
+        // it's fine if an outer part of the name is generic (like `typeof(List<int>.Enumerator)`). as that will be
+        // convertible to `nameof(List<>.Enumerator)`.  So we only need to check the type arguments directly on the type
+        // here, not on any containing types.
+        return namedType.TypeArguments.Length == 0;
     }
 }

src/Analyzers/VisualBasic/Analyzers/ConvertTypeofToNameof/VisualBasicConvertTypeOfToNameOfDiagnosticAnalyzer.vb

@@ -18,10 +18,6 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.ConvertTypeOfToNameOf
             MyBase.New(s_title)
         End Sub
 
-        Protected Overrides Function SupportsUnboundGenerics(options As ParseOptions) As Boolean
-            Return False
-        End Function
-
         Protected Overrides Function IsValidTypeofAction(context As OperationAnalysisContext) As Boolean
             Dim node = context.Operation.Syntax
             Dim compilation = context.Compilation