Fix sonarcloud issue

XmlSchemaClassGenerator/TypeModel.cs

@@ -118,6 +118,7 @@ public abstract class TypeModel
  public List<DocumentationModel> Documentation { get; private set; }
  public bool IsAnonymous { get; set; }
  public GeneratorConfiguration Configuration { get; private set; }
+ public virtual bool IsSubtype => false;
 
  protected TypeModel(GeneratorConfiguration configuration)
  {
@@ -148,7 +149,7 @@ protected void GenerateTypeAttribute(CodeTypeDeclaration typeDeclaration)
  var typeAttribute = new CodeAttributeDeclaration(CodeUtilities.CreateTypeReference(typeof(XmlTypeAttribute), Configuration),
  new CodeAttributeArgument(new CodePrimitiveExpression(XmlSchemaName.Name)),
  new CodeAttributeArgument("Namespace", new CodePrimitiveExpression(XmlSchemaName.Namespace)));
- if (IsAnonymous && (this is not ClassModel classModel || classModel.BaseClass == null))
+ if (IsAnonymous && !IsSubtype)
  {
  // don't generate AnonymousType if it's derived class, otherwise XmlSerializer will
  // complain with "InvalidOperationException: Cannot include anonymous type '...'"
@@ -259,6 +260,8 @@ public class ClassModel : ReferenceTypeModel
  public bool IsSubstitution { get; set; }
  public TypeModel BaseClass { get; set; }
  public List<ClassModel> DerivedTypes { get; set; }
+ public override bool IsSubtype => BaseClass != null;
+
  public ClassModel(GeneratorConfiguration configuration)
  : base(configuration)
  {