Fix S6964 FP: Properties with default values

analyzers/src/SonarAnalyzer.CSharp/Rules/AspNet/AvoidUnderPosting.cs

@@ -76,10 +76,12 @@ private static void CheckInvalidProperties(INamedTypeSymbol parameterType, Sonar
         var declaredProperties = new List<IPropertySymbol>();
         GetAllDeclaredProperties(parameterType, examinedTypes, declaredProperties);
         var invalidProperties = declaredProperties
-            .Where(x => !CanBeNull(x.Type) && !x.HasAttribute(KnownType.System_Text_Json_Serialization_JsonRequiredAttribute) && !x.IsRequired());
+            .Where(x => !CanBeNull(x.Type) && !x.HasAttribute(KnownType.System_Text_Json_Serialization_JsonRequiredAttribute) && !x.IsRequired())
+            .Select(x => x.GetFirstSyntaxRef())
+            .Where(x => !IsInitialized(x));
         foreach (var property in invalidProperties)
         {
-            context.ReportIssue(Rule, property.GetFirstSyntaxRef().GetIdentifier()?.GetLocation());
+            context.ReportIssue(Rule, property.GetIdentifier()?.GetLocation());
         }
     }
 
@@ -144,4 +146,7 @@ INamedTypeSymbol namedType when type.IsInSameAssembly(controllerType) => [namedT
 
     private static bool HasValidateNeverAttribute(ISymbol symbol) =>
         symbol.HasAttribute(KnownType.Microsoft_AspNetCore_Mvc_ModelBinding_Validation_ValidateNeverAttribute);
+
+    private static bool IsInitialized(SyntaxNode node) =>
+        node is ParameterSyntax { Default: not null } or PropertyDeclarationSyntax { Initializer: not null };
 }

analyzers/tests/SonarAnalyzer.Test/TestCases/AspNet/AvoidUnderPosting.CSharp12.cs

@@ -13,7 +13,7 @@ public class ModelWithPrimaryConstructor(int vp, int rvp, int nvp)
     public class ModelWithPrimaryAndParameterlessConstructor(int vp, int rvp, int nvp)
     {
         public ModelWithPrimaryAndParameterlessConstructor() : this(0, 0, 0) { }
-        public int ValueProperty { get; set; } = vp;                        // Noncompliant
+        public int ValueProperty { get; set; } = vp;                        // Compliant - the property has default value
     }
 
     public class DerivedFromController : Controller

analyzers/tests/SonarAnalyzer.Test/TestCases/AspNet/AvoidUnderPosting.CSharp9.cs

@@ -7,8 +7,9 @@ namespace CSharp9
     // https://learn.microsoft.com/en-us/aspnet/core/mvc/models/model-binding#constructor-binding-and-record-types
     public record RecordModel(
         int ValueProperty,                                                          // Noncompliant
-        [property: JsonRequired] int RequiredValueProperty,                             // without the property prefix the attribute would have been applied to the constructor parameter instead
-        int? NullableValueProperty);
+        [property: JsonRequired] int RequiredValueProperty,                         // without the property prefix the attribute would have been applied to the constructor parameter instead
+        int? NullableValueProperty,
+        int PropertyWithDefaultValue = 42);
 
     public class ModelUsedInController
     {

analyzers/tests/SonarAnalyzer.Test/TestCases/AspNet/AvoidUnderPosting.cs

@@ -24,6 +24,7 @@ public class ModelUsedInController
         internal int InternalProperty { get; set; }
         protected internal int ProtectedInternalProperty { get; set; }
         private int PrivateProperty { get; set; }
+        public int PropertyWithDefaultValue { get; set; } = 42;
         public int ReadOnlyProperty => 42;
         public int field = 42;