Add Field Attribute For Partial Properties (#218)

* Add Field Attribute For Partial Properties

* Rollback Copyright update

Author: ChrisPulman

src/ReactiveUI.SourceGenerators.Execute/TestViewModel.cs

@@ -236,6 +236,7 @@ public TestViewModel()
     /// The partial property test.
     /// </value>
     [Reactive]
+    [field: JsonInclude]
     public partial string? PartialPropertyTest { get; set; }
 
     /// <summary>

src/ReactiveUI.SourceGenerators.Roslyn/Core/Extensions/ContextExtensions.cs

@@ -65,7 +65,7 @@ internal static void GetForwardedAttributes(
             // Only look for attribute lists explicitly targeting the (generated) property. Roslyn will normally emit a
             // CS0657 warning (invalid target), but that is automatically suppressed by a dedicated diagnostic suppressor
             // that recognizes uses of this target specifically to support [ObservableAsProperty].
-            if (attributeList.Target?.Identifier is not SyntaxToken(SyntaxKind.PropertyKeyword))
+            if (attributeList.Target?.Identifier is not SyntaxToken(SyntaxKind.PropertyKeyword) && attributeList.Target?.Identifier is not SyntaxToken(SyntaxKind.FieldKeyword))
             {
                 continue;
             }

src/ReactiveUI.SourceGenerators.Roslyn/Diagnostics/Suppressions/ReactiveAttributeWithFieldTargetDiagnosticSuppressor.cs

@@ -0,0 +1,53 @@
+// Copyright (c) 2024 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using System.Collections.Immutable;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Diagnostics;
+using ReactiveUI.SourceGenerators.Extensions;
+using ReactiveUI.SourceGenerators.Helpers;
+using static ReactiveUI.SourceGenerators.Diagnostics.SuppressionDescriptors;
+
+namespace ReactiveUI.SourceGenerators.Diagnostics.Suppressions
+{
+    /// <summary>
+    /// ReactiveCommand Attribute With Field Or Property Target Diagnostic Suppressor.
+    /// </summary>
+    /// <seealso cref="DiagnosticSuppressor" />
+    [DiagnosticAnalyzer(LanguageNames.CSharp)]
+    public sealed class ReactiveAttributeWithFieldTargetDiagnosticSuppressor : DiagnosticSuppressor
+    {
+        /// <inheritdoc/>
+        public override ImmutableArray<SuppressionDescriptor> SupportedSuppressions => ImmutableArray.Create(FieldOrPropertyAttributeListForReactiveProperty);
+
+        /// <inheritdoc/>
+        public override void ReportSuppressions(SuppressionAnalysisContext context)
+        {
+            foreach (var diagnostic in context.ReportedDiagnostics)
+            {
+                var syntaxNode = diagnostic.Location.SourceTree?.GetRoot(context.CancellationToken).FindNode(diagnostic.Location.SourceSpan);
+
+                // Check that the target is effectively [field:] or [property:] over a method declaration, which is the case we're looking for
+                if (syntaxNode is AttributeTargetSpecifierSyntax { Parent.Parent: PropertyDeclarationSyntax propertyDeclaration, Identifier: SyntaxToken(SyntaxKind.FieldKeyword) })
+                {
+                    var semanticModel = context.GetSemanticModel(syntaxNode.SyntaxTree);
+
+                    // Get the method symbol from the first variable declaration
+                    ISymbol? declaredSymbol = semanticModel.GetDeclaredSymbol(propertyDeclaration, context.CancellationToken);
+
+                    // Check if the method is using [Reactive], in which case we should suppress the warning
+                    if (declaredSymbol is IPropertySymbol propertySymbol &&
+                        semanticModel.Compilation.GetTypeByMetadataName(AttributeDefinitions.ReactiveAttributeType) is INamedTypeSymbol reactiveSymbol &&
+                        propertySymbol.HasAttributeWithType(reactiveSymbol))
+                    {
+                        context.ReportSuppression(Suppression.Create(FieldOrPropertyAttributeListForReactiveProperty, diagnostic));
+                    }
+                }
+            }
+        }
+    }
+}

src/ReactiveUI.SourceGenerators.Roslyn/Reactive/ReactiveGenerator.Execute.cs

@@ -86,7 +86,15 @@ public sealed partial class ReactiveGenerator
         out var isReferenceTypeOrUnconstraindTypeParameter,
         out var includeMemberNotNullOnSetAccessor);
 
-        ImmutableArray<string> forwardedAttributesString = [];
+        var propertyDeclaration = (PropertyDeclarationSyntax)context.TargetNode;
+
+        context.GetForwardedAttributes(
+            builder,
+            propertySymbol,
+            propertyDeclaration.AttributeLists,
+            token,
+            out var forwardedAttributesString);
+
         token.ThrowIfCancellationRequested();
 
         // Get the containing type info

src/ReactiveUI.SourceGenerators.Roslyn/ReactiveUI.SourceGenerators.Roslyn.projitems

@@ -40,6 +40,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\Suppressions\OAPHMethodDoesNotNeedToBeStaticDiagnosticSuppressor.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\Suppressions\ObservableAsPropertyAttributeWithFieldNeverReadDiagnosticSuppressor.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\Suppressions\ReactiveAttributeWithPropertyTargetDiagnosticSuppressor.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\Suppressions\ReactiveAttributeWithFieldTargetDiagnosticSuppressor.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\Suppressions\ReactiveCommandAttributeWithFieldOrPropertyTargetDiagnosticSuppressor.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\Suppressions\ReactiveCommandMethodDoesNotNeedToBeStaticDiagnosticSuppressor.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Diagnostics\Suppressions\ReactiveFieldDoesNotNeedToBeReadOnlyDiagnosticSuppressor.cs" />