private static void Handle(SyntaxNodeAnalysisContext context) { if (!context.IsExcludedFromAnalysis() && context.ContainingSymbol is INamedTypeSymbol { IsAbstract : false, IsStatic : false } type&& type.IsAssignableToEither(KnownSymbols.IValueConverter, KnownSymbols.IMultiValueConverter, context.SemanticModel.Compilation) && context.Node is ClassDeclarationSyntax classDeclaration && type.DeclaredAccessibility != Accessibility.Private && type.DeclaredAccessibility != Accessibility.Protected) { if (!type.IsAssignableTo(KnownSymbols.MarkupExtension, context.SemanticModel.Compilation)) { if (ValueConverter.TryGetDefaultFieldsOrProperties(type, context.SemanticModel.Compilation, out var defaults)) { foreach (var fieldOrProperty in defaults) { if (fieldOrProperty.Value(context.CancellationToken) is { } assignedValue&& context.SemanticModel.TryGetType(assignedValue, context.CancellationToken, out var assignedType) && !TypeSymbolComparer.Equal(assignedType, type)) { context.ReportDiagnostic(Diagnostic.Create(Descriptors.WPF0074DefaultMemberOfWrongType, assignedValue.GetLocation())); } } } else if (!Virtual.HasVirtualOrAbstractOrProtectedMembers(type) && !type.Constructors.TryFirst(x => x.Parameters.Length > 0, out _) && !Mutable.HasMutableInstanceMembers(type) && !classDeclaration.Modifiers.Any(SyntaxKind.PartialKeyword)) { context.ReportDiagnostic(Diagnostic.Create(Descriptors.WPF0070ConverterDoesNotHaveDefaultField, classDeclaration.Identifier.GetLocation())); } } if (type.IsAssignableTo(KnownSymbols.IValueConverter, context.SemanticModel.Compilation)) { if (Attribute.TryFind(classDeclaration, KnownSymbols.ValueConversionAttribute, context.SemanticModel, context.CancellationToken, out var attribute)) { if (ValueConverter.TryGetConversionTypes(classDeclaration, context.SemanticModel, context.CancellationToken, out var sourceType, out var targetType)) { if (sourceType is { } &&
private static void Handle(SyntaxNodeAnalysisContext context) { if (!context.IsExcludedFromAnalysis() && context.ContainingSymbol is INamedTypeSymbol type && type.IsAssignableToEither(KnownSymbols.IValueConverter, KnownSymbols.IMultiValueConverter, context.Compilation) && context.Node is ClassDeclarationSyntax classDeclaration && !type.IsAbstract && type.DeclaredAccessibility != Accessibility.Private && type.DeclaredAccessibility != Accessibility.Protected) { if (!type.IsAssignableTo(KnownSymbols.MarkupExtension, context.Compilation)) { if (ValueConverter.TryGetDefaultFieldsOrProperties(type, context.Compilation, out var defaults)) { foreach (var fieldOrProperty in defaults) { if (fieldOrProperty.TryGetAssignedValue(context.CancellationToken, out var assignedValue) && context.SemanticModel.TryGetType(assignedValue, context.CancellationToken, out var assignedType) && !Equals(assignedType, type)) { context.ReportDiagnostic(Diagnostic.Create(Descriptors.WPF0074DefaultMemberOfWrongType, assignedValue.GetLocation())); } } } else if (!Virtual.HasVirtualOrAbstractOrProtectedMembers(type) && !type.Constructors.TryFirst(x => x.Parameters.Length > 0, out _) && !Mutable.HasMutableInstanceMembers(type)) { context.ReportDiagnostic(Diagnostic.Create(Descriptors.WPF0070ConverterDoesNotHaveDefaultField, classDeclaration.Identifier.GetLocation())); } } if (type.IsAssignableTo(KnownSymbols.IValueConverter, context.Compilation)) { if (Attribute.TryFind(classDeclaration, KnownSymbols.ValueConversionAttribute, context.SemanticModel, context.CancellationToken, out var attribute)) { if (ValueConverter.TryGetConversionTypes(classDeclaration, context.SemanticModel, context.CancellationToken, out var sourceType, out var targetType)) { if (sourceType != null && sourceType != QualifiedType.System.Object && attribute.TryFindArgument(0, "sourceType", out var arg) && arg.Expression is TypeOfExpressionSyntax sourceTypeOf && TypeOf.TryGetType(sourceTypeOf, type, context.SemanticModel, context.CancellationToken, out var argType) && !Equals(argType, sourceType)) { context.ReportDiagnostic(Diagnostic.Create(Descriptors.WPF0072ValueConversionMustUseCorrectTypes, arg.GetLocation(), sourceType)); } if (attribute.TryFindArgument(1, "targetType", out arg) && arg.Expression is TypeOfExpressionSyntax targetTypeOf && TypeOf.TryGetType(targetTypeOf, type, context.SemanticModel, context.CancellationToken, out argType) && !Equals(argType, targetType)) { context.ReportDiagnostic(Diagnostic.Create(Descriptors.WPF0072ValueConversionMustUseCorrectTypes, arg.GetLocation(), targetType)); } } } else { if (ValueConverter.TryGetConversionTypes(classDeclaration, context.SemanticModel, context.CancellationToken, out _, out _)) { context.ReportDiagnostic(Diagnostic.Create(Descriptors.WPF0071ConverterDoesNotHaveAttribute, classDeclaration.Identifier.GetLocation())); } else { context.ReportDiagnostic(Diagnostic.Create(Descriptors.WPF0073ConverterDoesNotHaveAttributeUnknownTypes, classDeclaration.Identifier.GetLocation())); } } } } }