[Rgen] Add properties to the data model in the transformer.

Update the transformer code to parse the properties from a binding. This
adds a all properties that the binding has that are either a property or
a field.

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

@@ -120,29 +120,6 @@ internal static bool Skip (MethodDeclarationSyntax methodDeclarationSyntax, Sema
 		return true;
 	}
 
-	delegate bool SkipDelegate<in T> (T declarationSyntax, SemanticModel semanticModel);
-
-	delegate bool TryCreateDelegate<in T, TR> (T declaration, RootContext context,
-		[NotNullWhen (true)] out TR? change)
-		where T : MemberDeclarationSyntax
-		where TR : struct;
-
-	static void GetMembers<T, TR> (TypeDeclarationSyntax baseDeclarationSyntax, RootContext context,
-		SkipDelegate<T> skip, TryCreateDelegate<T, TR> tryCreate, out ImmutableArray<TR> members)
-		where T : MemberDeclarationSyntax
-		where TR : struct
-	{
-		var bucket = ImmutableArray.CreateBuilder<TR> ();
-		var declarations = baseDeclarationSyntax.Members.OfType<T> ();
-		foreach (var declaration in declarations) {
-			if (skip (declaration, context.SemanticModel))
-				continue;
-			if (tryCreate (declaration, context, out var change))
-				bucket.Add (change.Value);
-		}
-
-		members = bucket.ToImmutable ();
-	}
 
 	/// <summary>
 	/// Internal constructor added for testing purposes.

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

@@ -2,12 +2,15 @@
 // Licensed under the MIT License.
 using System.Collections.Generic;
 using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Runtime.InteropServices;
 using System.Text;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.Macios.Generator.Availability;
+using Microsoft.Macios.Generator.Context;
 
 namespace Microsoft.Macios.Generator.DataModel;
 
@@ -155,4 +158,27 @@ public ImmutableArray<Method> Methods {
 		init => methods = value;
 	}
 
+	delegate bool SkipDelegate<in T> (T declarationSyntax, SemanticModel semanticModel);
+
+	delegate bool TryCreateDelegate<in T, TR> (T declaration, RootContext context,
+		[NotNullWhen (true)] out TR? change)
+		where T : MemberDeclarationSyntax
+		where TR : struct;
+
+	static void GetMembers<T, TR> (TypeDeclarationSyntax baseDeclarationSyntax, RootContext context,
+		SkipDelegate<T> skip, TryCreateDelegate<T, TR> tryCreate, out ImmutableArray<TR> members)
+		where T : MemberDeclarationSyntax
+		where TR : struct
+	{
+		var bucket = ImmutableArray.CreateBuilder<TR> ();
+		var declarations = baseDeclarationSyntax.Members.OfType<T> ();
+		foreach (var declaration in declarations) {
+			if (skip (declaration, context.SemanticModel))
+				continue;
+			if (tryCreate (declaration, context, out var change))
+				bucket.Add (change.Value);
+		}
+
+		members = bucket.ToImmutable ();
+	}
 }

src/rgen/Microsoft.Macios.Transformer/DataModel/Binding.Transformer.cs

@@ -181,6 +181,23 @@ static void GetInterfaceAndProtocols (INamedTypeSymbol symbol, out ImmutableArra
 		protocols = protocolsBucket.ToImmutable ();
 	}
 
+	/// <summary>
+	/// Decide if a property should be ignored as a change.
+	/// </summary>
+	/// <param name="propertyDeclarationSyntax">The property declaration under test.</param>
+	/// <param name="semanticModel">The semantic model of the compilation.</param>
+	/// <returns>True if the property should be ignored. False otherwise.</returns>
+	internal static bool Skip (PropertyDeclarationSyntax propertyDeclarationSyntax, SemanticModel semanticModel)
+	{
+		var propertySymbol = semanticModel.GetDeclaredSymbol (propertyDeclarationSyntax);
+		if (propertySymbol is null)
+			// skip if we cannot retrieve the symbol
+			return true;
+		var attributes = propertySymbol.GetAttributeData ();
+		// we will skip properties if they do not have the [Export] attribute or the [Field] attribute
+		return !attributes.HasExportAttribute () && !attributes.HasFieldAttribute ();
+	}
+
 	/// <summary>
 	/// Create a new binding based on the interface declaration. Because in the old SDK old the bindings
 	/// are represented by an interface, this constructor will ensure that the correct binding type is set.
@@ -213,6 +230,10 @@ internal Binding (InterfaceDeclarationSyntax interfaceDeclarationSyntax, INamedT
 			hasStaticFlag: HasStaticFlag || BindingInfo.BindingType == BindingType.Category // add static for categories
 		);
 		Modifiers = flags.ToClassModifiersArray ();
+
+		// loop over the different members and add them to the model
+		GetMembers<PropertyDeclarationSyntax, Property> (interfaceDeclarationSyntax, context, Skip, Property.TryCreate,
+			out properties);
 	}
 
 	/// <inheritdoc/>