[Rgen] Add the BindingData struct as part as the code struct. (#21874)

This addition allows the code emitters to access the binding type
configuration.

---------

Co-authored-by: GitHub Actions Autoformatter <github-actions-autoformatter@xamarin.com>

src/rgen/Microsoft.Macios.Bindings.Analyzer/Microsoft.Macios.Bindings.Analyzer.csproj

@@ -48,6 +48,9 @@
         <Compile Include="../Microsoft.Macios.Generator/Attributes/AttributeParsingError.cs" >
             <Link>Generator/Attributes/AttributeParsingError.cs</Link>
         </Compile>
+        <Compile Include="../Microsoft.Macios.Generator/Attributes/BindingTypeData.cs" >
+            <Link>Generator/Attributes/BindingTypeData.cs</Link>
+        </Compile>
         <Compile Include="../Microsoft.Macios.Generator/Attributes/ObsoletedOSPlatformData.cs" >
             <Link>Generator/Attributes/ObsoletedOSPlatformData.cs</Link>
         </Compile>

src/rgen/Microsoft.Macios.Generator/Attributes/BindingTypeData.cs

@@ -29,6 +29,9 @@ public static bool TryParse (AttributeData attributeData,
 		var count = attributeData.ConstructorArguments.Length;
 		string? name;
 		switch (count) {
+		case 0:
+			name = null;
+			break;
 		case 1:
 			name = (string?) attributeData.ConstructorArguments [0].Value!;
 			break;
@@ -106,6 +109,12 @@ public BindingTypeData (string? name)
 		Name = name;
 	}
 
+	public BindingTypeData (T? flags)
+	{
+		Name = null;
+		Flags = flags;
+	}
+
 	public BindingTypeData (string? name, T? flags)
 	{
 		Name = name;

src/rgen/Microsoft.Macios.Generator/AttributesNames.cs

@@ -5,9 +5,12 @@ namespace Microsoft.Macios.Generator;
 /// <summary>
 /// Contains all the names of the attributes that are used by the binding generator.
 /// </summary>
-public static class AttributesNames {
+static class AttributesNames {
 
 	public const string BindingAttribute = "ObjCBindings.BindingTypeAttribute";
+	public const string BindingCategoryAttribute = "ObjCBindings.BindingTypeAttribute<ObjCBindings.Category>";
+	public const string BindingClassAttribute = "ObjCBindings.BindingTypeAttribute<ObjCBindings.Class>";
+	public const string BindingProtocolAttribute = "ObjCBindings.BindingTypeAttribute<ObjCBindings.Protocol>";
 	public const string FieldAttribute = "ObjCBindings.FieldAttribute";
 	public const string EnumFieldAttribute = "ObjCBindings.FieldAttribute<ObjCBindings.EnumValue>";
 	public const string ExportFieldAttribute = "ObjCBindings.ExportAttribute<ObjCBindings.Field>";
@@ -17,6 +20,23 @@ public static class AttributesNames {
 	public const string UnsupportedOSPlatformAttribute = "System.Runtime.Versioning.UnsupportedOSPlatformAttribute";
 	public const string ObsoletedOSPlatformAttribute = "System.Runtime.Versioning.ObsoletedOSPlatformAttribute";
 
+
+	public static string? GetBindingTypeAttributeName<T> () where T : Enum
+	{
+		var type = typeof (T);
+		if (type == typeof (ObjCBindings.Category)) {
+			return BindingCategoryAttribute;
+		}
+		if (type == typeof (ObjCBindings.Class)) {
+			return BindingClassAttribute;
+		}
+		if (type == typeof (ObjCBindings.Protocol)) {
+			return BindingProtocolAttribute;
+		}
+
+		return null;
+	}
+
 	public static string? GetFieldAttributeName<T> () where T : Enum
 	{
 		// we cannot use a switch statement because typeof is not a constant value

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

@@ -18,27 +18,36 @@ readonly struct CodeChanges {
 	/// <summary>
 	/// Represents the type of binding that the code changes are for.
 	/// </summary>
-	public BindingType BindingType { get; } = BindingType.Unknown;
+	public BindingType BindingType => BindingData.BindingType;
 
+	readonly BindingData bindingData = default;
+	/// <summary>
+	/// Represents the binding data that will be used to generate the code.
+	/// </summary>
+	public BindingData BindingData => bindingData;
+
+	readonly string name = string.Empty;
 	/// <summary>
 	/// The name of the named type that generated the code change.
 	/// </summary>
-	public string Name { get; }
+	public string Name => name;
 
+	readonly ImmutableArray<string> namespaces = ImmutableArray<string>.Empty;
 	/// <summary>
 	/// The namespace that contains the named type that generated the code change.
 	/// </summary>
-	public ImmutableArray<string> Namespace { get; }
+	public ImmutableArray<string> Namespace => namespaces;
 
 	/// <summary>
 	/// Fully qualified name of the symbol that the code changes are for.
 	/// </summary>
 	public string FullyQualifiedSymbol { get; }
 
+	readonly SymbolAvailability availability = new ();
 	/// <summary>
 	/// The platform availability of the named type.
 	/// </summary>
-	public SymbolAvailability SymbolAvailability { get; }
+	public SymbolAvailability SymbolAvailability => availability;
 
 	/// <summary>
 	/// Changes to the attributes of the symbol.
@@ -208,19 +217,19 @@ static void GetMembers<T, TR> (TypeDeclarationSyntax baseDeclarationSyntax, Sema
 	/// <summary>
 	/// Internal constructor added for testing purposes.
 	/// </summary>
-	/// <param name="bindingType">The type of binding for the given code changes.</param>
+	/// <param name="bindingData">The binding data of binding for the given code changes.</param>
 	/// <param name="name">The name of the named type that created the code change.</param>
 	/// <param name="namespace">The namespace that contains the named type.</param>
 	/// <param name="fullyQualifiedSymbol">The fully qualified name of the symbol.</param>
 	/// <param name="symbolAvailability">The platform availability of the named symbol.</param>
-	internal CodeChanges (BindingType bindingType, string name, ImmutableArray<string> @namespace,
+	internal CodeChanges (BindingData bindingData, string name, ImmutableArray<string> @namespace,
 		string fullyQualifiedSymbol, SymbolAvailability symbolAvailability)
 	{
-		BindingType = bindingType;
-		Name = name;
-		Namespace = @namespace;
+		this.bindingData = bindingData;
+		this.name = name;
+		this.namespaces = @namespace;
 		FullyQualifiedSymbol = fullyQualifiedSymbol;
-		SymbolAvailability = symbolAvailability;
+		this.availability = symbolAvailability;
 	}
 
 	/// <summary>
@@ -230,8 +239,8 @@ internal CodeChanges (BindingType bindingType, string name, ImmutableArray<strin
 	/// <param name="semanticModel">The semantic model of the compilation.</param>
 	CodeChanges (EnumDeclarationSyntax enumDeclaration, SemanticModel semanticModel)
 	{
-		(Name, Namespace, SymbolAvailability) = semanticModel.GetSymbolData (enumDeclaration);
-		BindingType = BindingType.SmartEnum;
+		semanticModel.GetSymbolData (
+			enumDeclaration, BindingType.SmartEnum, out name, out namespaces, out availability, out bindingData);
 		FullyQualifiedSymbol = enumDeclaration.GetFullyQualifiedIdentifier ();
 		Attributes = enumDeclaration.GetAttributeCodeChanges (semanticModel);
 		Modifiers = [.. enumDeclaration.Modifiers];
@@ -263,8 +272,8 @@ internal CodeChanges (BindingType bindingType, string name, ImmutableArray<strin
 	/// <param name="semanticModel">The semantic model of the compilation.</param>
 	CodeChanges (ClassDeclarationSyntax classDeclaration, SemanticModel semanticModel)
 	{
-		(Name, Namespace, SymbolAvailability) = semanticModel.GetSymbolData (classDeclaration);
-		BindingType = BindingType.Class;
+		semanticModel.GetSymbolData (
+			classDeclaration, BindingType.Class, out name, out namespaces, out availability, out bindingData);
 		FullyQualifiedSymbol = classDeclaration.GetFullyQualifiedIdentifier ();
 		Attributes = classDeclaration.GetAttributeCodeChanges (semanticModel);
 		Modifiers = [.. classDeclaration.Modifiers];
@@ -287,8 +296,8 @@ internal CodeChanges (BindingType bindingType, string name, ImmutableArray<strin
 	/// <param name="semanticModel">The semantic model of the compilation.</param>
 	CodeChanges (InterfaceDeclarationSyntax interfaceDeclaration, SemanticModel semanticModel)
 	{
-		(Name, Namespace, SymbolAvailability) = semanticModel.GetSymbolData (interfaceDeclaration);
-		BindingType = BindingType.Protocol;
+		semanticModel.GetSymbolData (
+			interfaceDeclaration, BindingType.Protocol, out name, out namespaces, out availability, out bindingData);
 		FullyQualifiedSymbol = interfaceDeclaration.GetFullyQualifiedIdentifier ();
 		Attributes = interfaceDeclaration.GetAttributeCodeChanges (semanticModel);
 		Modifiers = [.. interfaceDeclaration.Modifiers];
@@ -323,7 +332,7 @@ internal CodeChanges (BindingType bindingType, string name, ImmutableArray<strin
 	public override string ToString ()
 	{
 		var sb = new StringBuilder ("Changes: {");
-		sb.Append ($"BindingType: '{BindingType}', Name: '{Name}', Namespace: [");
+		sb.Append ($"BindingData: '{BindingData}', Name: '{Name}', Namespace: [");
 		sb.AppendJoin (", ", Namespace);
 		sb.Append ($"], FullyQualifiedSymbol: '{FullyQualifiedSymbol}', SymbolAvailability: {SymbolAvailability}, ");
 		sb.Append ("Attributes: [");

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

@@ -2,24 +2,18 @@
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.Macios.Generator.Availability;
+using Microsoft.Macios.Generator.DataModel;
 
 namespace Microsoft.Macios.Generator.Extensions;
 
 static class SemanticModelExtensions {
 
-	/// <summary>
-	/// Returns the name and namespace of the symbol that has been declared in the passed base type declaration
-	/// syntax node.
-	/// </summary>
-	/// <param name="self">The current semantic model.</param>
-	/// <param name="declaration">The named type declaration syntaxt.</param>
-	/// <returns>A tuple containing the name and namespace of the type. If they could not be calculated, they will
-	/// be set to be string.Empty.</returns>
-	public static (string Name, ImmutableArray<string> Namespace, SymbolAvailability SymbolAvailability) GetSymbolData (this SemanticModel self,
-		BaseTypeDeclarationSyntax declaration)
+	public static void GetSymbolData (ISymbol? symbol,
+		out string name,
+		out ImmutableArray<string> namespaces,
+		out SymbolAvailability symbolAvailability)
 	{
-		var symbol = self.GetDeclaredSymbol (declaration);
-		var name = symbol?.Name ?? string.Empty;
+		name = symbol?.Name ?? string.Empty;
 		var bucket = ImmutableArray.CreateBuilder<string> ();
 		var ns = symbol?.ContainingNamespace;
 		while (ns is not null) {
@@ -28,7 +22,31 @@ public static (string Name, ImmutableArray<string> Namespace, SymbolAvailability
 				bucket.Insert (0, ns.Name);
 			ns = ns.ContainingNamespace;
 		}
-		var availability = symbol?.GetSupportedPlatforms () ?? new SymbolAvailability ();
-		return (name, bucket.ToImmutableArray (), availability);
+
+		symbolAvailability = symbol?.GetSupportedPlatforms () ?? new SymbolAvailability ();
+		namespaces = bucket.ToImmutableArray ();
+	}
+
+	public static void GetSymbolData (this SemanticModel self, BaseTypeDeclarationSyntax declaration,
+		BindingType bindingType,
+		out string name,
+		out ImmutableArray<string> namespaces,
+		out SymbolAvailability symbolAvailability,
+		out BindingData bindingData)
+	{
+		var symbol = self.GetDeclaredSymbol (declaration);
+		GetSymbolData (symbol, out name, out namespaces, out symbolAvailability);
+		if (symbol is null)
+			bindingData = default;
+		else {
+			bindingData = bindingType switch {
+				BindingType.Category => new BindingData (symbol.GetBindingData<ObjCBindings.Category> ()),
+				BindingType.Class => new BindingData (symbol.GetBindingData<ObjCBindings.Class> ()),
+				BindingType.Protocol => new BindingData (symbol.GetBindingData<ObjCBindings.Protocol> ()),
+				BindingType.SmartEnum => new BindingData (BindingType.SmartEnum, symbol.GetBindingData ()),
+				_ => default,
+			};
+		}
 	}
+
 }

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

@@ -125,6 +125,47 @@ public static SymbolAvailability GetSupportedPlatforms (this ISymbol symbol)
 		return availability;
 	}
 
+	public static BindingTypeData GetBindingData (this ISymbol symbol)
+	{
+		var boundAttributes = symbol.GetAttributes ();
+		if (boundAttributes.Length == 0) {
+			// no attrs in the symbol, therefore the symbol is supported in all platforms
+			return default;
+		}
+		// we are looking for the basic BindingAttribute attr
+		foreach (var attributeData in boundAttributes) {
+			var attrName = attributeData.AttributeClass?.ToDisplayString ();
+			if (string.IsNullOrEmpty (attrName) || attrName != AttributesNames.BindingAttribute)
+				continue;
+			if (BindingTypeData.TryParse (attributeData, out var bindingData)) {
+				return bindingData.Value;
+			}
+		}
+
+		return default;
+	}
+
+	public static BindingTypeData<T> GetBindingData<T> (this ISymbol symbol) where T : Enum
+	{
+		var boundAttributes = symbol.GetAttributes ();
+		if (boundAttributes.Length == 0) {
+			// no attrs in the symbol, therefore the symbol is supported in all platforms
+			return default;
+		}
+
+		var targetAttrName = AttributesNames.GetBindingTypeAttributeName<T> ();
+		foreach (var attributeData in boundAttributes) {
+			var attrName = attributeData.AttributeClass?.ToDisplayString ();
+			if (string.IsNullOrEmpty (attrName) || attrName != targetAttrName)
+				continue;
+			if (BindingTypeData<T>.TryParse (attributeData, out var bindingData)) {
+				return bindingData.Value;
+			}
+		}
+
+		return default;
+	}
+
 	/// <summary>
 	/// Retrieve the data of an export attribute on a symbol.
 	/// </summary>

tests/rgen/Microsoft.Macios.Generator.Tests/AttributesNamesTests.cs

@@ -18,4 +18,16 @@ public void GetFieldAttributeName<T> (T @enum, string? expectedName) where T : E
 		Assert.NotNull (@enum);
 		Assert.Equal (expectedName, AttributesNames.GetFieldAttributeName<T> ());
 	}
+
+	[Theory]
+	[InlineData (StringComparison.Ordinal, null)]
+	[InlineData (EnumValue.Default, null)]
+	[InlineData (Category.Default, AttributesNames.BindingCategoryAttribute)]
+	[InlineData (Class.Default, AttributesNames.BindingClassAttribute)]
+	[InlineData (Protocol.Default, AttributesNames.BindingProtocolAttribute)]
+	public void GetBindingTypeAttributeName<T> (T @enum, string? expectedName) where T : Enum
+	{
+		Assert.NotNull (@enum);
+		Assert.Equal (expectedName, AttributesNames.GetBindingTypeAttributeName<T> ());
+	}
 }