[RGen] Add extension method to know if a symbol is wrapped.

src/rgen/Microsoft.Macios.Generator/DataModel/TypeInfo.Generator.cs

@@ -7,6 +7,16 @@
 namespace Microsoft.Macios.Generator.DataModel;
 
 readonly partial struct TypeInfo {
+
+	/// <summary>
+	/// Return if the type represents a wrapped object from the objc world.
+	/// </summary>
+	public bool IsWrapped { get; init; }
+
+	/// <summary>
+	/// Returns, if the type is an array, if its elements are a wrapped object from the objc world.
+	/// </summary>
+	public bool ArrayElementTypeIsWrapped { get; init; }
 
 	internal TypeInfo (ITypeSymbol symbol) :
 		this (
@@ -18,7 +28,6 @@ symbol is IArrayTypeSymbol arrayTypeSymbol
 		IsNullable = symbol.NullableAnnotation == NullableAnnotation.Annotated;
 		IsBlittable = symbol.IsBlittable ();
 		IsSmartEnum = symbol.IsSmartEnum ();
-		IsArray = symbol is IArrayTypeSymbol;
 		IsReferenceType = symbol.IsReferenceType;
 		IsStruct = symbol.TypeKind == TypeKind.Struct;
 		IsInterface = symbol.TypeKind == TypeKind.Interface;
@@ -33,6 +42,13 @@ symbol is IArrayTypeSymbol arrayTypeSymbol
 			parents: out parents,
 			interfaces: out interfaces);
 
+		IsWrapped = symbol.IsWrapped (isNSObject);
+		if (symbol is IArrayTypeSymbol arraySymbol) {
+			IsArray = true;
+			ArrayElementTypeIsWrapped = arraySymbol.ElementType.IsWrapped ();
+		}
+		IsArray = symbol is IArrayTypeSymbol;
+
 		// try to get the named type symbol to have more educated decisions
 		var namedTypeSymbol = symbol as INamedTypeSymbol;
 

src/rgen/Microsoft.Macios.Generator/Extensions/TypeSymbolExtensions.Core.cs

@@ -13,6 +13,11 @@
 namespace Microsoft.Macios.Generator.Extensions;
 
 static partial class TypeSymbolExtensions {
+
+	const string nativeObjectInterface = "ObjCRuntime.INativeObject";
+	const string nsObjectClass = "Foundation.NSObject";
+	const string dictionaryContainerClass = "Foundation.DictionaryContainer";
+
 	/// <summary>
 	/// Retrieve a dictionary with the attribute data of all the attributes attached to a symbol. Because
 	/// an attribute can appear more than once, the valus are a collection of attribute data.
@@ -417,11 +422,7 @@ public static void GetInheritance (
 		out ImmutableArray<string> parents,
 		out ImmutableArray<string> interfaces)
 	{
-		const string nativeObjectInterface = "ObjCRuntime.INativeObject";
-		const string nsObjectClass = "Foundation.NSObject";
-		const string dictionaryContainerClass = "Foundation.DictionaryContainer";
-
-		isNSObject = false;
+		isNSObject = symbol.ToDisplayString ().Trim() == nsObjectClass;
 		isNativeObject = false;
 		isDictionaryContainer = false;
 

src/rgen/Microsoft.Macios.Generator/Extensions/TypeSymbolExtensions.Generator.cs

@@ -3,6 +3,8 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.Macios.Generator.Attributes;
 using Microsoft.Macios.Generator.Availability;
@@ -213,4 +215,32 @@ public static bool NeedsStret (this ITypeSymbol returnType, Compilation compilat
 
 		return ArmNeedStret (returnType, compilation);
 	}
+
+	/// <summary>
+	/// A type is considered wrapped if it is an Interface or is an child of the NSObject class or the NSObject
+	/// itself.
+	/// </summary>
+	/// <param name="symbol">The symbol to check if it is wrapped.</param>
+	/// <param name="isNSObject">If the symbol is a NSObject of inherits from an NSObject.</param>
+	/// <returns>True if the ymbol is considered to be wrapped.</returns>
+	public static bool IsWrapped (this ITypeSymbol symbol, bool isNSObject)
+		=> symbol.TypeKind == TypeKind.Interface || isNSObject;
+
+	/// <summary>
+	/// A type is considered wrapped if it is an Interface or is an child of the NSObject class or the NSObject
+	/// itself.
+	/// </summary>
+	/// <param name="symbol">The symbol to check if it is wrapped.</param>
+	/// <returns>True if the ymbol is considered to be wrapped.</returns>
+	public static bool IsWrapped (this ITypeSymbol symbol)
+	{
+		symbol.GetInheritance (
+			isNSObject: out bool isNSObject,
+			isNativeObject: out bool _,
+			isDictionaryContainer: out bool _,
+			parents: out ImmutableArray<string> _,
+			interfaces: out ImmutableArray<string> _);
+		// either we are a NSObject or we are a subclass of it
+		return IsWrapped (symbol, isNSObject);
+	}
 }

tests/rgen/Microsoft.Macios.Generator.Tests/Extensions/TypeSymbolExtensionsTests.cs

@@ -1702,5 +1702,162 @@ void IsBlittable (ApplePlatform platform, string inputText, bool expectedResult)
 		Assert.NotNull (symbol);
 		Assert.Equal (expectedResult, symbol.Type.IsBlittable ());
 	}
+
+	class TestDataIsWrapped : IEnumerable<object []> {
+		public IEnumerator<object []> GetEnumerator ()
+		{
+			const string stringProperty = @"
+using System;
+using ObjCBindings;
+
+namespace NS;
+
+[BindingType<Class>]
+public partial class MyClass {
+	public string Property { get; set; }
+}
+";
+			yield return [stringProperty, false];
+
+			const string nsUuidProperty = @"
+using System;
+using Foundation;
+using ObjCBindings;
+
+namespace NS;
+
+[BindingType<Class>]
+public partial class MyClass {
+	public NSUuid Property { get; set; }
+}
+";
+			yield return [nsUuidProperty, true];
+
+			const string nmatrix4Property = @"
+using System;
+using CoreGraphics;
+using ObjCBindings;
+
+namespace NS;
+
+[BindingType<Class>]
+public partial class MyClass {
+	public NMatrix4 Property { get; set; }
+}
+";
+
+			yield return [nmatrix4Property, false];
+
+			const string nativeHandleProperty = @"
+using System;
+using ObjCRuntime;
+using ObjCBindings;
+
+namespace NS;
+
+[BindingType<Class>]
+public partial class MyClass {
+	public NativeHandle Property { get; set; }
+}
+";
+			yield return [nativeHandleProperty, false];
+
+			const string nsZoneProperty = @"
+using System;
+using Foundation;
+using ObjCBindings;
+
+namespace NS;
+
+[BindingType<Class>]
+public partial class MyClass {
+	public NSZone Property { get; set; }
+}
+";
+			yield return [nsZoneProperty, false];
+
+			const string nsobjectProperty = @"
+using System;
+using Foundation;
+using ObjCBindings;
+
+namespace NS;
+
+[BindingType<Class>]
+public partial class MyClass {
+	public NSObject Property { get; set; }
+}
+";
+			yield return [nsobjectProperty, true];
+
+			const string nssetProperty = @"
+using System;
+using Foundation;
+using ObjCBindings;
+
+namespace NS;
+
+[BindingType<Class>]
+public partial class MyClass {
+	public NSSet<NSObject> Property { get; set; }
+}
+";
+			yield return [nssetProperty, true];
+
+
+			const string mtlDeviceProperty = @"
+using System;
+using Metal;
+using ObjCBindings;
+
+namespace NS;
+
+[BindingType<Class>]
+public partial class MyClass {
+	public IMTLDevice Property { get; set; }
+}
+";
+			yield return [mtlDeviceProperty, true];
+
+			const string EnumProperty = @"
+using System;
+using System.Runtime.InteropServices;
+using ObjCBindings;
+
+namespace NS;
+
+public enum MyEnum : ulong {
+	First,
+	Second,
+}
+
+[BindingType<Class>]
+public partial class MyClass {
+	public MyEnum Property { get; set; }
+}
+";
+			yield return [EnumProperty, false];
+		}
+
+		IEnumerator IEnumerable.GetEnumerator () => GetEnumerator ();
+	}
+
+	[Theory]
+	[AllSupportedPlatformsClassData<TestDataIsWrapped>]
+	void IsWrapped (ApplePlatform platform, string inputText, bool expectedResult)
+	{
+		var (compilation, syntaxTrees) = CreateCompilation (platform, sources: inputText);
+		Assert.Single (syntaxTrees);
+		var declaration = syntaxTrees [0].GetRoot ()
+			.DescendantNodes ()
+			.OfType<PropertyDeclarationSyntax> ()
+			.FirstOrDefault ();
+		Assert.NotNull (declaration);
+		var semanticModel = compilation.GetSemanticModel (syntaxTrees [0]);
+		Assert.NotNull (semanticModel);
+		var symbol = semanticModel.GetDeclaredSymbol (declaration);
+		Assert.NotNull (symbol);
+		Assert.Equal (expectedResult, symbol.Type.IsWrapped ());
+	}
 
 }