fix: properly reset serialization provider in visitor

codegen/generator/src/OpenAILibraryGenerator.cs

@@ -1,4 +1,3 @@
-using System;
 using System.ComponentModel.Composition;
 using Microsoft.TypeSpec.Generator;
 using Microsoft.TypeSpec.Generator.ClientModel;
@@ -16,11 +15,12 @@ public OpenAILibraryGenerator(GeneratorContext context) : base(context) { }
         protected override void Configure()
         {
             base.Configure();
+            // This should be first, as it recomputes the type
+            AddVisitor(new NonAbstractPublicTypesVisitor());
             AddVisitor(new ConstructorFixupVisitor());
             AddVisitor(new KindRenameVisitor());
             AddVisitor(new VisibilityVisitor());
             AddVisitor(new ContentInnerCollectionDefinedVisitor());
-            AddVisitor(new NonAbstractPublicTypesVisitor());
             AddVisitor(new PageOrderRemovalVisitor(this));
             AddVisitor(new OmittedTypesVisitor());
             AddVisitor(new InvariantFormatAdditionalPropertiesVisitor());

codegen/generator/src/Visitors/NonAbstractPublicTypesVisitor.cs

@@ -1,7 +1,6 @@
 using Microsoft.TypeSpec.Generator.ClientModel;
 using Microsoft.TypeSpec.Generator.Primitives;
 using Microsoft.TypeSpec.Generator.Providers;
-using System.Reflection;
 
 namespace OpenAILibraryPlugin.Visitors;
 
@@ -17,16 +16,22 @@ protected override TypeProvider VisitType(TypeProvider type)
             && type.DeclarationModifiers.HasFlag(TypeSignatureModifiers.Abstract)
             && type.CustomCodeView?.DeclarationModifiers.HasFlag(TypeSignatureModifiers.Abstract) == false)
         {
+            var serializationProviders = type.SerializationProviders;
+
+            // ensure we build the serialization attributes before we change the modifiers
+            foreach (var serialization in serializationProviders)
+            {
+                _ = serialization.Attributes;
+            }
+
             // Keep types defined in custom code without 'abstract' non-abstract
+            type.Update(modifiers: type.DeclarationModifiers & ~TypeSignatureModifiers.Abstract);
 
-            // To do: replace with this line when dependencies updated to include modifier support
-            // type.Update(modifiers: type.DeclarationModifiers & ~TypeSignatureModifiers.Abstract);
-            // To do: remove this reflection-based workaround for the above:
-            FieldInfo privateModifiersInfo = typeof(TypeProvider)
-                .GetField("_declarationModifiers", BindingFlags.Instance | BindingFlags.NonPublic)!;
-            TypeSignatureModifiers privateValue = (TypeSignatureModifiers)privateModifiersInfo.GetValue(type)!;
-            privateValue &= ~TypeSignatureModifiers.Abstract;
-            privateModifiersInfo.SetValue(type, privateValue);
+            // reset the serialization to pick up the new modifiers while keeping any serialization attributes
+            foreach (var serialization in serializationProviders)
+            {
+                serialization.Update(attributes: serialization.Attributes, reset: true);
+            }
         }
         return type;
     }