[Rgen] Add a property invocations struct to be used with the syntaxt …

…factory.

This will allow to have a struct that will contain all the needed
invocation data.

We need to update some of the uses froma CompilationUnit to a StatementSyntax,
which actually makes the code better overall while letting us use a
throw statement as the invocation statement for a property.

src/rgen/Microsoft.Macios.Generator/Emitters/BindingSyntaxFactory.ObjCRuntime.cs

@@ -800,40 +800,7 @@ internal static LocalDeclarationStatementSyntax Using (LocalDeclarationStatement
 		return sb.ToString ();
 	}
 
-	public static (string? Getter, string? Setter) GetObjCMessageSendMethods (in Property property,
-		bool isSuper = false, bool isStret = false)
-	{
-		if (property.IsProperty) {
-			// the getter and the setter depend of the accessors that have been set for the property, we do not want
-			// to calculate things that we won't use. The export data used will also depend if the getter/setter has a
-			// export attribute attached
-			var getter = property.GetAccessor (AccessorKind.Getter);
-			string? getterMsgSend = null;
-			if (getter is not null) {
-				var getterExportData = getter.Value.ExportPropertyData ?? property.ExportPropertyData;
-				if (getterExportData is not null) {
-					getterMsgSend = GetObjCMessageSendMethodName (getterExportData.Value, property.ReturnType, [],
-						isSuper, isStret);
-				}
-			}
-
-			var setter = property.GetAccessor (AccessorKind.Setter);
-			string? setterMsgSend = null;
-			if (setter is not null) {
-				var setterExportData = setter.Value.ExportPropertyData ?? property.ExportPropertyData;
-				if (setterExportData is not null) {
-					setterMsgSend = GetObjCMessageSendMethodName (setterExportData.Value, TypeInfo.Void,
-						[property.ValueParameter], isSuper, isStret);
-				}
-			}
-
-			return (Getter: getterMsgSend, Setter: setterMsgSend);
-		}
-
-		return default;
-	}
-
-	public static string? GetObjCMessageSendMethod (in Method method, bool isSuper = false, bool isStret = false)
+	internal static string? GetObjCMessageSendMethod (in Method method, bool isSuper = false, bool isStret = false)
 		=> GetObjCMessageSendMethodName (method.ExportMethodData, method.ReturnType, method.Parameters, isSuper,
 			isStret);
 }

src/rgen/Microsoft.Macios.Generator/Emitters/BindingSyntaxFactory.Property.cs

@@ -0,0 +1,51 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using Microsoft.Macios.Generator.DataModel;
+using TypeInfo = Microsoft.Macios.Generator.DataModel.TypeInfo;
+
+namespace Microsoft.Macios.Generator.Emitters;
+
+static partial class BindingSyntaxFactory {
+
+	internal static (string? Getter, string? Setter) GetObjCMessageSendMethods (in Property property,
+		bool isSuper = false, bool isStret = false)
+	{
+		if (property.IsProperty) {
+			// the getter and the setter depend of the accessors that have been set for the property, we do not want
+			// to calculate things that we won't use. The export data used will also depend if the getter/setter has a
+			// export attribute attached
+			var getter = property.GetAccessor (AccessorKind.Getter);
+			string? getterMsgSend = null;
+			if (getter is not null) {
+				var getterExportData = getter.Value.ExportPropertyData ?? property.ExportPropertyData;
+				if (getterExportData is not null) {
+					getterMsgSend = GetObjCMessageSendMethodName (getterExportData.Value, property.ReturnType, [],
+						isSuper, isStret);
+				}
+			}
+
+			var setter = property.GetAccessor (AccessorKind.Setter);
+			string? setterMsgSend = null;
+			if (setter is not null) {
+				var setterExportData = setter.Value.ExportPropertyData ?? property.ExportPropertyData;
+				if (setterExportData is not null) {
+					setterMsgSend = GetObjCMessageSendMethodName (setterExportData.Value, TypeInfo.Void,
+						[property.ValueParameter], isSuper, isStret);
+				}
+			}
+
+			return (Getter: getterMsgSend, Setter: setterMsgSend);
+		}
+
+		return default;
+	}
+
+	internal static PropertyInvocations GetInvocations (in Property property)
+	{
+		return new () {
+			Getter = (ThrowNotImplementedException (), ThrowNotImplementedException ()),
+			Setter = (ThrowNotImplementedException (), ThrowNotImplementedException ()),
+		};
+	}
+}

src/rgen/Microsoft.Macios.Generator/Emitters/BindingSyntaxFactory.Runtime.cs

@@ -13,7 +13,7 @@ static partial class BindingSyntaxFactory {
 	public const string Runtime = "Runtime";
 	public const string ClassPtr = "class_ptr";
 
-	public static CompilationUnitSyntax GetNSObject (string nsObjectType, ArgumentListSyntax argumentList,
+	public static StatementSyntax GetNSObject (string nsObjectType, ArgumentListSyntax argumentList,
 		bool suppressNullableWarning = false)
 		=> StaticInvocationGenericExpression (Runtime, "GetNSObject", nsObjectType, argumentList,
 			suppressNullableWarning);

src/rgen/Microsoft.Macios.Generator/Emitters/BindingSyntaxFactory.cs

@@ -22,7 +22,7 @@ static ArgumentSyntax GetLiteralExpressionArgument (SyntaxKind kind, string lite
 		return Argument (LiteralExpression (kind, Literal (literal)));
 	}
 
-	static CompilationUnitSyntax StaticInvocationExpression (string staticClassName, string methodName,
+	static StatementSyntax StaticInvocationExpression (string staticClassName, string methodName,
 		SyntaxNodeOrToken [] argumentList, bool suppressNullableWarning = false)
 	{
 		var invocation = InvocationExpression (
@@ -33,18 +33,14 @@ static CompilationUnitSyntax StaticInvocationExpression (string staticClassName,
 			)
 		).WithArgumentList (ArgumentList (SeparatedList<ArgumentSyntax> (argumentList)).NormalizeWhitespace ());
 
-		var compilationUnit = CompilationUnit ().WithMembers (
-			SingletonList<MemberDeclarationSyntax> (
-				GlobalStatement (
-					ExpressionStatement (
-						suppressNullableWarning
-							? PostfixUnaryExpression (SyntaxKind.SuppressNullableWarningExpression, invocation)
-							: invocation))));
-		return compilationUnit;
+		return ExpressionStatement (
+			suppressNullableWarning
+				? PostfixUnaryExpression (SyntaxKind.SuppressNullableWarningExpression, invocation)
+				: invocation);
 	}
 
 
-	static CompilationUnitSyntax StaticInvocationGenericExpression (string staticClassName, string methodName,
+	static StatementSyntax StaticInvocationGenericExpression (string staticClassName, string methodName,
 		string genericName,
 		ArgumentListSyntax argumentList, bool suppressNullableWarning = false)
 	{
@@ -60,41 +56,41 @@ static CompilationUnitSyntax StaticInvocationGenericExpression (string staticCla
 			)
 		).WithArgumentList (argumentList);
 
-		var compilationUnit = CompilationUnit ().WithMembers (
-			SingletonList<MemberDeclarationSyntax> (
-				GlobalStatement (
-					ExpressionStatement (
-						suppressNullableWarning
-							? PostfixUnaryExpression (SyntaxKind.SuppressNullableWarningExpression, invocation)
-							: invocation
-					))));
-		return compilationUnit;
+		return ExpressionStatement (
+			suppressNullableWarning
+				? PostfixUnaryExpression (SyntaxKind.SuppressNullableWarningExpression, invocation)
+				: invocation);
 	}
 
-	static CompilationUnitSyntax ThrowException (string type, string message)
+	static StatementSyntax ThrowException (string type, string? message = null)
 	{
-		var argumentList = ArgumentList (SingletonSeparatedList (
+		var throwExpression = ObjectCreationExpression (IdentifierName (type));
+
+		if (message is not null) {
+			var argumentList = ArgumentList (SingletonSeparatedList (
 				GetLiteralExpressionArgument (SyntaxKind.StringLiteralExpression, message)
 			)).WithLeadingTrivia (Space);
 
-		var throwExpression = ThrowStatement (
-			ObjectCreationExpression (IdentifierName (type))
-				.WithArgumentList (argumentList)).NormalizeWhitespace ();
+			throwExpression = throwExpression.WithArgumentList (argumentList).NormalizeWhitespace ();
+		} else {
+			throwExpression = throwExpression.WithArgumentList (ArgumentList ().WithLeadingTrivia (Space));
+		}
 
-		return CompilationUnit ().WithMembers (
-			SingletonList<MemberDeclarationSyntax> (
-				GlobalStatement (throwExpression)));
+		return ThrowStatement (throwExpression).NormalizeWhitespace ();
 	}
 
-	static CompilationUnitSyntax ThrowNotSupportedException (string message)
+	static StatementSyntax ThrowNotSupportedException (string message)
 		=> ThrowException (type: "NotSupportedException", message: message);
 
+	static StatementSyntax ThrowNotImplementedException ()
+		=> ThrowException (type: "NotImplementedException");
+
 	/// <summary>
 	/// Generates the syntax to declare the variable used by a field property.  
 	/// </summary>
 	/// <param name="property">The field property whose backing variable we want to generate.</param>
 	/// <returns>The variable declaration syntax.</returns>
-	public static CompilationUnitSyntax FieldPropertyBackingVariable (in Property property)
+	internal static CompilationUnitSyntax FieldPropertyBackingVariable (in Property property)
 	{
 		var variableType = property.ReturnType.FullyQualifiedName;
 		if (property.ReturnType.SpecialType is SpecialType.System_IntPtr or SpecialType.System_UIntPtr

src/rgen/Microsoft.Macios.Generator/Emitters/ClassEmitter.cs

@@ -155,6 +155,8 @@ void EmitProperties (in BindingContext context, TabbedWriter<StringWriter> class
 			if (property.IsField)
 				// ignore fields
 				continue;
+			// use the factory to generate all the needed invocations for the current 
+			var invocations = GetInvocations (property);
 
 			// we expect to always at least have a getter
 			var getter = property.GetAccessor (AccessorKind.Getter);
@@ -180,19 +182,19 @@ void EmitProperties (in BindingContext context, TabbedWriter<StringWriter> class
 						getterBlock.WriteRaw (
 $@"{tempDeclaration}
 if (IsDirectBinding) {{
-	{tempVar} = throw new NotImplementedException();
+	{tempVar} = {invocations.Getter.Send}
 }} else {{
-	{tempVar} = throw new NotImplementedException();
+	{tempVar} = {invocations.Getter.SendSuper}
 }}
 return {tempVar};
 ");
 					} else {
 						getterBlock.WriteRaw (
-@"if (IsDirectBinding) {
-	throw new NotImplementedException();
-} else {
-	throw new NotImplementedException();
-}
+$@"if (IsDirectBinding) {{
+	{invocations.Getter.Send}
+}} else {{
+	{invocations.Getter.SendSuper}
+}}
 ");
 					}
 				}

src/rgen/Microsoft.Macios.Generator/Emitters/PropertyInvocations.cs

@@ -0,0 +1,22 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+
+namespace Microsoft.Macios.Generator.Emitters;
+
+/// <summary>
+/// Represents all the invocations of a property.
+/// </summary>
+readonly record struct PropertyInvocations {
+
+	/// <summary>
+	/// Invocations for the getter.
+	/// </summary>
+	public (StatementSyntax Send, StatementSyntax SendSuper) Getter { get; init; }
+
+	/// <summary>
+	/// Invocations for the setter.
+	/// </summary>
+	public (StatementSyntax Send, StatementSyntax SendSuper) Setter { get; init; }
+}