Fix issue where typeof/sizeof weren't classified properly in FindRefs (#79372)

Author: CyrusNajmabadi

src/EditorFeatures/Test2/FindReferences/FindReferencesTests.NamedTypeSymbols.vb

@@ -254,6 +254,66 @@ class var<T> { }
             Await TestAPIAndFeature(input, kind, host)
         End Function
 
+        <WpfTheory, CombinatorialData>
+        <WorkItem("https://github.com/dotnet/roslyn/issues/79100")>
+        Public Async Function TestNamedType_TypeOfOperator_Name(kind As TestKind, host As TestHost) As Task
+            Dim input =
+<Workspace>
+    <Project Language="C#" CommonReferences="true">
+        <Document>
+        class {|Definition:Celsius|}
+        {
+            public {|Definition:Celsius|}()
+            {
+                System.Type t = typeof({|ValueUsageInfo.Name:[|$$Celsius|]|});
+            }
+        }
+        </Document>
+    </Project>
+</Workspace>
+            Await TestAPIAndFeature(input, kind, host)
+        End Function
+
+        <WpfTheory, CombinatorialData>
+        <WorkItem("https://github.com/dotnet/roslyn/issues/79100")>
+        Public Async Function TestNamedType_SizeOfOperator_Name(kind As TestKind, host As TestHost) As Task
+            Dim input =
+<Workspace>
+    <Project Language="C#" CommonReferences="true">
+        <Document>
+        class {|Definition:Celsius|}
+        {
+            public {|Definition:Celsius|}()
+            {
+                int t = sizeof({|ValueUsageInfo.Name:[|$$Celsius|]|});
+            }
+        }
+        </Document>
+    </Project>
+</Workspace>
+            Await TestAPIAndFeature(input, kind, host)
+        End Function
+
+        <WpfTheory, CombinatorialData>
+        <WorkItem("https://github.com/dotnet/roslyn/issues/79100")>
+        Public Async Function TestNamedType_NameOfOperator_Name(kind As TestKind, host As TestHost) As Task
+            Dim input =
+<Workspace>
+    <Project Language="C#" CommonReferences="true">
+        <Document>
+        class {|Definition:Celsius|}
+        {
+            public {|Definition:Celsius|}()
+            {
+                string t = nameof({|ValueUsageInfo.Name:[|$$Celsius|]|});
+            }
+        }
+        </Document>
+    </Project>
+</Workspace>
+            Await TestAPIAndFeature(input, kind, host)
+        End Function
+
         <WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/539799")>
         <WpfTheory, CombinatorialData>
         Public Async Function TestNamedType_InaccessibleType(kind As TestKind, host As TestHost) As Task

src/Workspaces/Core/Portable/FindSymbols/FindReferences/Finders/AbstractReferenceFinder.cs

@@ -608,7 +608,17 @@ protected static SymbolUsageInfo GetSymbolUsageInfo(
         while (syntaxFacts.IsQualifiedName(topNameNode.Parent))
             topNameNode = topNameNode.Parent;
 
-        var isInNamespaceNameContext = syntaxFacts.IsBaseNamespaceDeclaration(topNameNode.Parent);
+        var parent = topNameNode?.Parent;
+
+        // typeof/sizeof are a special case where we don't want to return a TypeOrNamespaceUsageInfo, but rather a ValueUsageInfo.Name.
+        // This brings it in line with nameof(...), making all those operators appear in a similar fashion.
+        if (parent?.RawKind == syntaxFacts.SyntaxKinds.TypeOfExpression ||
+            parent?.RawKind == syntaxFacts.SyntaxKinds.SizeOfExpression)
+        {
+            return new(ValueUsageInfo.Name, typeOrNamespaceUsageInfoOpt: null);
+        }
+
+        var isInNamespaceNameContext = syntaxFacts.IsBaseNamespaceDeclaration(parent);
         return syntaxFacts.IsInNamespaceOrTypeContext(topNameNode)
             ? SymbolUsageInfo.Create(GetTypeOrNamespaceUsageInfo())
             : GetSymbolUsageInfoCommon();
@@ -677,18 +687,12 @@ SymbolUsageInfo GetSymbolUsageInfoCommon()
                 if (operation is IObjectCreationOperation)
                     return SymbolUsageInfo.Create(TypeOrNamespaceUsageInfo.ObjectCreation);
 
-                switch (operation?.Parent)
-                {
-                    case INameOfOperation:
-                    case ITypeOfOperation:
-                    case ISizeOfOperation:
-                        return SymbolUsageInfo.Create(ValueUsageInfo.Name);
-                }
+                // Note: sizeof/typeof also return 'name', but are handled above in GetSymbolUsageInfo.
+                if (operation?.Parent is INameOfOperation)
+                    return SymbolUsageInfo.Create(ValueUsageInfo.Name);
 
                 if (node.IsPartOfStructuredTrivia())
-                {
                     return SymbolUsageInfo.Create(ValueUsageInfo.Name);
-                }
 
                 var symbolInfo = semanticModel.GetSymbolInfo(node, cancellationToken);
                 if (symbolInfo.Symbol != null)

src/Workspaces/SharedUtilitiesAndExtensions/Compiler/CSharp/Services/SyntaxFacts/CSharpSyntaxKinds.cs

@@ -118,11 +118,13 @@ public int Convert<TSyntaxKind>(TSyntaxKind kind) where TSyntaxKind : struct
     public int ReferenceNotEqualsExpression => (int)SyntaxKind.NotEqualsExpression;
     public int SimpleAssignmentExpression => (int)SyntaxKind.SimpleAssignmentExpression;
     public int SimpleMemberAccessExpression => (int)SyntaxKind.SimpleMemberAccessExpression;
+    public int? SizeOfExpression => (int)SyntaxKind.SizeOfExpression;
     public int? SuppressNullableWarningExpression => (int)SyntaxKind.SuppressNullableWarningExpression;
     public int TernaryConditionalExpression => (int)SyntaxKind.ConditionalExpression;
     public int ThisExpression => (int)SyntaxKind.ThisExpression;
     public int? ThrowExpression => (int)SyntaxKind.ThrowExpression;
     public int TupleExpression => (int)SyntaxKind.TupleExpression;
+    public int TypeOfExpression => (int)SyntaxKind.TypeOfExpression;
 
     public int? AndPattern => (int)SyntaxKind.AndPattern;
     public int? ConstantPattern => (int)SyntaxKind.ConstantPattern;

src/Workspaces/SharedUtilitiesAndExtensions/Compiler/Core/Extensions/SymbolUsageInfo.cs

@@ -2,10 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
 using System.Diagnostics;
 using System.Runtime.Serialization;
-using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis;
 
@@ -15,7 +13,7 @@ namespace Microsoft.CodeAnalysis;
 /// For methods, fields, properties, events, locals and parameters, this corresponds to values from <see cref="ValueUsageInfo"/>.
 /// </summary>
 [DataContract]
-internal readonly struct SymbolUsageInfo : IEquatable<SymbolUsageInfo>
+internal readonly record struct SymbolUsageInfo
 {
     public static readonly SymbolUsageInfo None = Create(ValueUsageInfo.None);
 
@@ -45,28 +43,4 @@ public bool IsReadFrom()
 
     public bool IsWrittenTo()
         => ValueUsageInfoOpt.HasValue && ValueUsageInfoOpt.Value.IsWrittenTo();
-
-    public bool IsNameOnly()
-        => ValueUsageInfoOpt.HasValue && ValueUsageInfoOpt.Value.IsNameOnly();
-
-    public override bool Equals(object? obj)
-        => obj is SymbolUsageInfo && Equals((SymbolUsageInfo)obj);
-
-    public bool Equals(SymbolUsageInfo other)
-    {
-        if (ValueUsageInfoOpt.HasValue)
-        {
-            return other.ValueUsageInfoOpt.HasValue &&
-                ValueUsageInfoOpt.Value == other.ValueUsageInfoOpt.Value;
-        }
-        else
-        {
-            RoslynDebug.Assert(TypeOrNamespaceUsageInfoOpt.HasValue);
-            return other.TypeOrNamespaceUsageInfoOpt.HasValue &&
-                TypeOrNamespaceUsageInfoOpt.Value == other.TypeOrNamespaceUsageInfoOpt.Value;
-        }
-    }
-
-    public override int GetHashCode()
-        => Hash.Combine(((int?)ValueUsageInfoOpt)?.GetHashCode() ?? 0, ((int?)TypeOrNamespaceUsageInfoOpt)?.GetHashCode() ?? 0);
 }

src/Workspaces/SharedUtilitiesAndExtensions/Compiler/Core/Services/SyntaxFacts/ISyntaxKinds.cs

@@ -161,11 +161,13 @@ internal interface ISyntaxKinds
     int ReferenceNotEqualsExpression { get; }
     int SimpleAssignmentExpression { get; }
     int SimpleMemberAccessExpression { get; }
+    int? SizeOfExpression { get; }
     int? SuppressNullableWarningExpression { get; }
     int TernaryConditionalExpression { get; }
     int ThisExpression { get; }
     int? ThrowExpression { get; }
     int TupleExpression { get; }
+    int TypeOfExpression { get; }
 
     #endregion
 

src/Workspaces/SharedUtilitiesAndExtensions/Compiler/VisualBasic/Services/SyntaxFacts/VisualBasicSyntaxKinds.vb

@@ -120,11 +120,13 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.LanguageService
         Public ReadOnly Property ReferenceNotEqualsExpression As Integer = SyntaxKind.IsNotExpression Implements ISyntaxKinds.ReferenceNotEqualsExpression
         Public ReadOnly Property SimpleAssignmentExpression As Integer = SyntaxKind.SimpleAssignmentStatement Implements ISyntaxKinds.SimpleAssignmentExpression
         Public ReadOnly Property SimpleMemberAccessExpression As Integer = SyntaxKind.SimpleMemberAccessExpression Implements ISyntaxKinds.SimpleMemberAccessExpression
+        Public ReadOnly Property SizeOfExpression As Integer? Implements ISyntaxKinds.SizeOfExpression
         Public ReadOnly Property SuppressNullableWarningExpression As Integer? Implements ISyntaxKinds.SuppressNullableWarningExpression
         Public ReadOnly Property TernaryConditionalExpression As Integer = SyntaxKind.TernaryConditionalExpression Implements ISyntaxKinds.TernaryConditionalExpression
         Public ReadOnly Property ThisExpression As Integer = SyntaxKind.MeExpression Implements ISyntaxKinds.ThisExpression
         Public ReadOnly Property ThrowExpression As Integer? Implements ISyntaxKinds.ThrowExpression
         Public ReadOnly Property TupleExpression As Integer = SyntaxKind.TupleExpression Implements ISyntaxKinds.TupleExpression
+        Public ReadOnly Property TypeOfExpression As Integer = SyntaxKind.GetTypeExpression Implements ISyntaxKinds.TypeOfExpression
 
         Public ReadOnly Property AndPattern As Integer? Implements ISyntaxKinds.AndPattern
         Public ReadOnly Property ConstantPattern As Integer? Implements ISyntaxKinds.ConstantPattern