Support applying attributes to properties and fields that are created to back...

Support applying attributes to properties and fields that are created to back primary constructor parameters in records. (#45908)

Closes #44691.

src/Compilers/CSharp/Portable/Symbols/OverriddenOrHiddenMembersHelpers.cs

@@ -129,9 +129,22 @@ private static OverriddenOrHiddenMembersResult MakeOverriddenOrHiddenMembersWork
                 return MakeInterfaceOverriddenOrHiddenMembers(member, memberIsFromSomeCompilation);
             }
 
-            Symbol bestMatch = null;
-            ArrayBuilder<Symbol> hiddenBuilder = null;
+            ArrayBuilder<Symbol> hiddenBuilder;
+            ImmutableArray<Symbol> overriddenMembers;
+            ImmutableArray<Symbol> runtimeOverriddenMembers;
+            FindOverriddenOrHiddenMembers(member, containingType, memberIsFromSomeCompilation, out hiddenBuilder, out overriddenMembers, out runtimeOverriddenMembers);
+
+            ImmutableArray<Symbol> hiddenMembers = hiddenBuilder == null ? ImmutableArray<Symbol>.Empty : hiddenBuilder.ToImmutableAndFree();
+            return OverriddenOrHiddenMembersResult.Create(overriddenMembers, hiddenMembers, runtimeOverriddenMembers);
+        }
 
+        private static void FindOverriddenOrHiddenMembers(Symbol member, NamedTypeSymbol containingType, bool memberIsFromSomeCompilation,
+            out ArrayBuilder<Symbol> hiddenBuilder,
+            out ImmutableArray<Symbol> overriddenMembers,
+            out ImmutableArray<Symbol> runtimeOverriddenMembers)
+        {
+            Symbol bestMatch = null;
+            hiddenBuilder = null;
             for (NamedTypeSymbol currType = containingType.BaseTypeNoUseSiteDiagnostics;
                 (object)currType != null && (object)bestMatch == null && hiddenBuilder == null;
                 currType = currType.BaseTypeNoUseSiteDiagnostics)
@@ -149,12 +162,19 @@ private static OverriddenOrHiddenMembersResult MakeOverriddenOrHiddenMembersWork
 
             // Based on bestMatch, find other methods that will be overridden, hidden, or runtime overridden
             // (in bestMatch.ContainingType).
-            ImmutableArray<Symbol> overriddenMembers;
-            ImmutableArray<Symbol> runtimeOverriddenMembers;
             FindRelatedMembers(member.IsOverride, memberIsFromSomeCompilation, member.Kind, bestMatch, out overriddenMembers, out runtimeOverriddenMembers, ref hiddenBuilder);
+        }
 
-            ImmutableArray<Symbol> hiddenMembers = hiddenBuilder == null ? ImmutableArray<Symbol>.Empty : hiddenBuilder.ToImmutableAndFree();
-            return OverriddenOrHiddenMembersResult.Create(overriddenMembers, hiddenMembers, runtimeOverriddenMembers);
+        public static Symbol FindFirstHiddenMemberIfAny(Symbol member, bool memberIsFromSomeCompilation)
+        {
+            ArrayBuilder<Symbol> hiddenBuilder;
+            FindOverriddenOrHiddenMembers(member, member.ContainingType, memberIsFromSomeCompilation, out hiddenBuilder,
+                overriddenMembers: out _, runtimeOverriddenMembers: out _);
+
+            Symbol result = hiddenBuilder?.FirstOrDefault();
+            hiddenBuilder?.Free();
+
+            return result;
         }
 
         /// <summary>

src/Compilers/CSharp/Portable/Symbols/SignatureOnlyPropertySymbol.cs

@@ -75,7 +75,7 @@ internal sealed class SignatureOnlyPropertySymbol : PropertySymbol
 
         public override bool IsVirtual { get { throw ExceptionUtilities.Unreachable; } }
 
-        public override bool IsOverride { get { throw ExceptionUtilities.Unreachable; } }
+        public override bool IsOverride => false;
 
         public override bool IsAbstract { get { throw ExceptionUtilities.Unreachable; } }
 

src/Compilers/CSharp/Portable/Symbols/Source/SourceComplexParameterSymbol.cs

@@ -341,7 +341,18 @@ public override string MetadataName
 
         AttributeLocation IAttributeTargetSymbol.DefaultAttributeLocation => AttributeLocation.Parameter;
 
-        AttributeLocation IAttributeTargetSymbol.AllowedAttributeLocations => AttributeLocation.Parameter;
+        AttributeLocation IAttributeTargetSymbol.AllowedAttributeLocations
+        {
+            get
+            {
+                if (SynthesizedRecordPropertySymbol.HaveCorrespondingSynthesizedRecordPropertySymbol(this))
+                {
+                    return AttributeLocation.Parameter | AttributeLocation.Property | AttributeLocation.Field;
+                }
+
+                return AttributeLocation.Parameter;
+            }
+        }
 
         /// <summary>
         /// Symbol to copy bound attributes from, or null if the attributes are not shared among multiple source parameter symbols.

src/Compilers/CSharp/Portable/Symbols/Source/SourceMemberContainerSymbol.cs

@@ -3079,16 +3079,24 @@ ImmutableArray<PropertySymbol> addProperties(ImmutableArray<ParameterSymbol> rec
                 {
                     bool isInherited = false;
                     var syntax = param.GetNonNullSyntaxNode();
-                    var property = new SynthesizedRecordPropertySymbol(this, syntax, param, isOverride: false, diagnostics);
-                    if (!memberSignatures.TryGetValue(property, out var existingMember))
+
+                    var targetProperty = new SignatureOnlyPropertySymbol(param.Name,
+                                                                         this,
+                                                                         ImmutableArray<ParameterSymbol>.Empty,
+                                                                         RefKind.None,
+                                                                         param.TypeWithAnnotations,
+                                                                         ImmutableArray<CustomModifier>.Empty,
+                                                                         isStatic: false,
+                                                                         ImmutableArray<PropertySymbol>.Empty);
+
+                    if (!memberSignatures.TryGetValue(targetProperty, out var existingMember))
                     {
-                        Debug.Assert(property.OverriddenOrHiddenMembers.OverriddenMembers.Length == 0); // property is not virtual and should not have overrides
-                        existingMember = property.OverriddenOrHiddenMembers.HiddenMembers.FirstOrDefault();
+                        existingMember = OverriddenOrHiddenMembersHelpers.FindFirstHiddenMemberIfAny(targetProperty, memberIsFromSomeCompilation: true);
                         isInherited = true;
                     }
                     if (existingMember is null)
                     {
-                        addProperty(property);
+                        addProperty(new SynthesizedRecordPropertySymbol(this, syntax, param, isOverride: false, diagnostics));
                     }
                     else if (existingMember is PropertySymbol { IsStatic: false, GetMethod: { } } prop
                         && prop.TypeWithAnnotations.Equals(param.TypeWithAnnotations, TypeCompareKind.AllIgnoreOptions))

src/Compilers/CSharp/Portable/Symbols/Source/SourcePropertySymbol.cs

@@ -139,6 +139,8 @@ private static bool HasInitializer(SyntaxNode syntax)
         public override SyntaxList<AttributeListSyntax> AttributeDeclarationSyntaxList
             => ((BasePropertyDeclarationSyntax)CSharpSyntaxNode).AttributeLists;
 
+        public override IAttributeTargetSymbol AttributesOwner => this;
+
         private static void GetAccessorDeclarations(
             CSharpSyntaxNode syntaxNode,
             DiagnosticBag diagnostics,

src/Compilers/CSharp/Portable/Symbols/Source/SourcePropertySymbolBase.cs

@@ -705,8 +705,6 @@ internal CSharpSyntaxNode CSharpSyntaxNode
             }
         }
 
-        public abstract SyntaxList<AttributeListSyntax> AttributeDeclarationSyntaxList { get; }
-
         internal SyntaxTree SyntaxTree
         {
             get
@@ -980,7 +978,11 @@ private SynthesizedSealedPropertyAccessor MakeSynthesizedSealedAccessor()
 
         #region Attributes
 
-        IAttributeTargetSymbol IAttributeTargetSymbol.AttributesOwner => this;
+        public abstract SyntaxList<AttributeListSyntax> AttributeDeclarationSyntaxList { get; }
+
+        public abstract IAttributeTargetSymbol AttributesOwner { get; }
+
+        IAttributeTargetSymbol IAttributeTargetSymbol.AttributesOwner => AttributesOwner;
 
         AttributeLocation IAttributeTargetSymbol.DefaultAttributeLocation => AttributeLocation.Property;
 

src/Compilers/CSharp/Portable/Symbols/Synthesized/Records/SynthesizedRecordClone.cs

@@ -119,12 +119,12 @@ internal override void GenerateMethodBody(TypeCompilationState compilationState,
         {
             var F = new SyntheticBoundNodeFactory(this, ContainingType.GetNonNullSyntaxNode(), compilationState, diagnostics);
 
-            var members = ContainingType.GetMembers(WellKnownMemberNames.InstanceConstructorName);
+            var members = ContainingType.InstanceConstructors;
             foreach (var member in members)
             {
                 var ctor = (MethodSymbol)member;
-                if (ctor.ParameterCount == 1 &&
-                    ctor.Parameters[0].Type.Equals(ContainingType, TypeCompareKind.ConsiderEverything))
+                if (ctor.ParameterCount == 1 && ctor.Parameters[0].RefKind == RefKind.None &&
+                    ctor.Parameters[0].Type.Equals(ContainingType, TypeCompareKind.AllIgnoreOptions))
                 {
                     F.CloseMethod(F.Return(F.New(ctor, F.This())));
                     return;

src/Compilers/CSharp/Portable/Symbols/Synthesized/Records/SynthesizedRecordEqualityContractProperty.cs

@@ -15,7 +15,7 @@
 
 namespace Microsoft.CodeAnalysis.CSharp.Symbols
 {
-    internal sealed class SynthesizedRecordEqualityContractProperty : SourcePropertySymbolBase, IAttributeTargetSymbol
+    internal sealed class SynthesizedRecordEqualityContractProperty : SourcePropertySymbolBase
     {
         internal const string PropertyName = "EqualityContract";
 
@@ -52,11 +52,10 @@ internal sealed class SynthesizedRecordEqualityContractProperty : SourceProperty
 
         public override ImmutableArray<SyntaxReference> DeclaringSyntaxReferences => ImmutableArray<SyntaxReference>.Empty;
 
-        IAttributeTargetSymbol IAttributeTargetSymbol.AttributesOwner => this;
-
-        AttributeLocation IAttributeTargetSymbol.AllowedAttributeLocations => AttributeLocation.None;
+        public override SyntaxList<AttributeListSyntax> AttributeDeclarationSyntaxList
+            => new SyntaxList<AttributeListSyntax>();
 
-        AttributeLocation IAttributeTargetSymbol.DefaultAttributeLocation => AttributeLocation.None;
+        public override IAttributeTargetSymbol AttributesOwner => this;
 
         protected override Location TypeLocation
             => ContainingType.Locations[0];
@@ -64,9 +63,6 @@ protected override Location TypeLocation
         protected override SyntaxTokenList GetModifierTokens(SyntaxNode syntax)
             => new SyntaxTokenList();
 
-        public override SyntaxList<AttributeListSyntax> AttributeDeclarationSyntaxList
-            => new SyntaxList<AttributeListSyntax>();
-
         protected override void CheckForBlockAndExpressionBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics)
         {
             // Nothing to do here

src/Compilers/CSharp/Portable/Symbols/Synthesized/Records/SynthesizedRecordPropertySymbol.cs

@@ -11,9 +11,9 @@
 
 namespace Microsoft.CodeAnalysis.CSharp.Symbols
 {
-    internal sealed class SynthesizedRecordPropertySymbol : SourcePropertySymbolBase, IAttributeTargetSymbol
+    internal sealed class SynthesizedRecordPropertySymbol : SourcePropertySymbolBase
     {
-        public ParameterSymbol BackingParameter { get; }
+        public SourceParameterSymbol BackingParameter { get; }
 
         public SynthesizedRecordPropertySymbol(
             SourceMemberContainerTypeSymbol containingType,
@@ -42,14 +42,11 @@ internal sealed class SynthesizedRecordPropertySymbol : SourcePropertySymbolBase
                 hasParameters: false,
                 diagnostics)
         {
-            BackingParameter = backingParameter;
+            BackingParameter = (SourceParameterSymbol)backingParameter;
         }
 
-        IAttributeTargetSymbol IAttributeTargetSymbol.AttributesOwner => this;
 
-        AttributeLocation IAttributeTargetSymbol.AllowedAttributeLocations => AttributeLocation.None;
-
-        AttributeLocation IAttributeTargetSymbol.DefaultAttributeLocation => AttributeLocation.None;
+        public override IAttributeTargetSymbol AttributesOwner => BackingParameter as IAttributeTargetSymbol ?? this;
 
         protected override Location TypeLocation
             => ((ParameterSyntax)CSharpSyntaxNode).Type!.Location;
@@ -58,7 +55,7 @@ protected override SyntaxTokenList GetModifierTokens(SyntaxNode syntax)
             => new SyntaxTokenList();
 
         public override SyntaxList<AttributeListSyntax> AttributeDeclarationSyntaxList
-            => new SyntaxList<AttributeListSyntax>();
+            => BackingParameter.AttributeDeclarationList;
 
         protected override void CheckForBlockAndExpressionBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics)
         {
@@ -112,5 +109,10 @@ protected override TypeWithAnnotations ComputeType(Binder? binder, SyntaxNode sy
         protected override bool HasPointerTypeSyntactically
             // Since we already bound the type, don't bother looking at syntax
             => TypeWithAnnotations.DefaultType.IsPointerOrFunctionPointer();
+
+        public static bool HaveCorrespondingSynthesizedRecordPropertySymbol(SourceParameterSymbol parameter)
+        {
+            return parameter.ContainingType.GetMembersUnordered().Any((s, parameter) => (s as SynthesizedRecordPropertySymbol)?.BackingParameter == (object)parameter, parameter);
+        }
     }
 }

src/Compilers/CSharp/Portable/Symbols/Synthesized/SynthesizedBackingFieldSymbol.cs

@@ -41,7 +41,7 @@ internal sealed class SynthesizedBackingFieldSymbol : FieldSymbolWithAttributesA
         }
 
         protected override IAttributeTargetSymbol AttributeOwner
-            => _property;
+            => _property.AttributesOwner;
 
         internal override Location ErrorLocation
             => _property.Location;

src/Compilers/Core/Portable/Collections/ImmutableArrayExtensions.cs

@@ -359,6 +359,22 @@ public static ImmutableArray<T> WhereAsArray<T>(this ImmutableArray<T> array, Fu
             }
         }
 
+        public static bool Any<T, TArg>(this ImmutableArray<T> array, Func<T, TArg, bool> predicate, TArg arg)
+        {
+            int n = array.Length;
+            for (int i = 0; i < n; i++)
+            {
+                var a = array[i];
+
+                if (predicate(a, arg))
+                {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
         /// <summary>
         /// Casts the immutable array of a Type to an immutable array of its base type.
         /// </summary>

src/Compilers/Test/Utilities/CSharp/CSharpTestBase.cs

@@ -1506,6 +1506,11 @@ internal static IEnumerable<string> GetAttributeStrings(ImmutableArray<CSharpAtt
             return attributes.Select(a => a.ToString());
         }
 
+        internal static IEnumerable<string> GetAttributeStrings(IEnumerable<CSharpAttributeData> attributes)
+        {
+            return attributes.Select(a => a.ToString());
+        }
+
         #endregion
 
         #region Documentation Comments