Added XML docs copying from fields to generated properties

Author: Sergio0694

Microsoft.Toolkit.Mvvm.SourceGenerators/ComponentModel/ObservablePropertyGenerator.SyntaxReceiver.cs

@@ -34,14 +34,16 @@ public void OnVisitSyntaxNode(GeneratorSyntaxContext context)
                 if (context.Node is FieldDeclarationSyntax { AttributeLists: { Count: > 0 } } fieldDeclaration &&
                     context.SemanticModel.Compilation.GetTypeByMetadataName("Microsoft.Toolkit.Mvvm.ComponentModel.ObservablePropertyAttribute") is INamedTypeSymbol attributeSymbol)
                 {
+                    SyntaxTriviaList leadingTrivia = fieldDeclaration.GetLeadingTrivia();
+
                     foreach (VariableDeclaratorSyntax variableDeclarator in fieldDeclaration.Declaration.Variables)
                     {
                         if (context.SemanticModel.GetDeclaredSymbol(variableDeclarator) is IFieldSymbol fieldSymbol &&
                             fieldSymbol.GetAttributes().FirstOrDefault(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, attributeSymbol)) is AttributeData attributeData &&
                             attributeData.ApplicationSyntaxReference is SyntaxReference syntaxReference &&
                             syntaxReference.GetSyntax() is AttributeSyntax attributeSyntax)
                         {
-                            this.gatheredInfo.Add(new Item(variableDeclarator, fieldSymbol, attributeSyntax, attributeData));
+                            this.gatheredInfo.Add(new Item(leadingTrivia, variableDeclarator, fieldSymbol, attributeSyntax, attributeData));
                         }
                     }
                 }
@@ -50,11 +52,13 @@ attributeData.ApplicationSyntaxReference is SyntaxReference syntaxReference &&
             /// <summary>
             /// A model for a group of item representing a discovered type to process.
             /// </summary>
+            /// <param name="LeadingTrivia">The leading trivia for the field declaration.</param>
             /// <param name="FieldDeclarator">The <see cref="VariableDeclaratorSyntax"/> instance for the target field variable declaration.</param>
             /// <param name="FieldSymbol">The <see cref="IFieldSymbol"/> instance for <paramref name="FieldDeclarator"/>.</param>
             /// <param name="AttributeSyntax">The <see cref="AttributeSyntax"/> instance for the target attribute over <paramref name="FieldDeclarator"/>.</param>
             /// <param name="AttributeData">The <see cref="AttributeData"/> instance for <paramref name="AttributeSyntax"/>.</param>
             public sealed record Item(
+                SyntaxTriviaList LeadingTrivia,
                 VariableDeclaratorSyntax FieldDeclarator,
                 IFieldSymbol FieldSymbol,
                 AttributeSyntax AttributeSyntax,

Microsoft.Toolkit.Mvvm.SourceGenerators/ComponentModel/ObservablePropertyGenerator.cs

@@ -71,7 +71,7 @@ private static void OnExecute(
             var classDeclarationSyntax =
                 ClassDeclaration(classDeclarationSymbol.Name)
                 .WithModifiers(classDeclaration.Modifiers)
-                .AddMembers(items.Select(static item => CreatePropertyDeclaration(item.FieldSymbol)).ToArray());
+                .AddMembers(items.Select(static item => CreatePropertyDeclaration(item.LeadingTrivia, item.FieldSymbol)).ToArray());
 
             TypeDeclarationSyntax typeDeclarationSyntax = classDeclarationSyntax;
 
@@ -112,10 +112,11 @@ private static void OnExecute(
         /// <summary>
         /// Creates a <see cref="PropertyDeclarationSyntax"/> instance for a specified field.
         /// </summary>
+        /// <param name="leadingTrivia">The leading trivia for the field to process.</param>
         /// <param name="fieldSymbol">The input <see cref="IFieldSymbol"/> instance to process.</param>
         /// <returns>A generated <see cref="PropertyDeclarationSyntax"/> instance for the input field.</returns>
         [Pure]
-        private static PropertyDeclarationSyntax CreatePropertyDeclaration(IFieldSymbol fieldSymbol)
+        private static PropertyDeclarationSyntax CreatePropertyDeclaration(SyntaxTriviaList leadingTrivia, IFieldSymbol fieldSymbol)
         {
             // Get the field type and the target property name
             string
@@ -152,6 +153,7 @@ private static PropertyDeclarationSyntax CreatePropertyDeclaration(IFieldSymbol
 
             // Construct the generated property as follows:
             //
+            // <FIELD_TRIVIA>
             // [DebuggerNonUserCode]
             // [ExcludeFromCodeCoverage]
             // public <FIELD_TYPE> <PROPERTY_NAME>
@@ -172,6 +174,7 @@ private static PropertyDeclarationSyntax CreatePropertyDeclaration(IFieldSymbol
                 .AddAttributeLists(
                     AttributeList(SingletonSeparatedList(Attribute(IdentifierName("DebuggerNonUserCode")))),
                     AttributeList(SingletonSeparatedList(Attribute(IdentifierName("ExcludeFromCodeCoverage")))))
+                .WithLeadingTrivia(leadingTrivia)
                 .AddModifiers(Token(SyntaxKind.PublicKeyword))
                 .AddAccessorListAccessors(
                     AccessorDeclaration(SyntaxKind.GetAccessorDeclaration)

UnitTests/UnitTests.NetCore/Mvvm/Test_ObservablePropertyAttribute.cs

@@ -52,6 +52,9 @@ public void Test_ObservablePropertyAttribute_Events()
 
         public partial class SampleModel : ObservableObject
         {
+            /// <summary>
+            /// This is a sample data field within <see cref="SampleModel"/> of type <see cref="int"/>.
+            /// </summary>
             [ObservableProperty]
             private int data;
         }