BuggedGenerator providing options to report warning, error or throw exception within CodeGeneration.Roslyn generator

ErrorGenerator.cs

using System;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using CodeGeneration.Roslyn;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.Syntax;

namespace BuggedGenerator
{
    public class ErrorGenerator : ICodeGenerator
    {
        private readonly AttributeData attributeData;

        private DiagnosticDescriptor WarnDescriptor { get; }
         = new DiagnosticDescriptor(
             "TEST001",
             "Custom Warning Diagnostic Title",
             "Message format for warning is here",
             "TST",
             DiagnosticSeverity.Warning,
             isEnabledByDefault: true);
        private DiagnosticDescriptor ErrorDescriptor { get; }
         = new DiagnosticDescriptor(
             "TEST002",
             "Custom Error Diagnostic Title",
             "Message format for error is here",
             "TST",
             DiagnosticSeverity.Error,
             isEnabledByDefault: true);

        public ErrorGenerator(AttributeData attributeData)
        {
            this.attributeData = attributeData;
        }

        public Task<SyntaxList<MemberDeclarationSyntax>> GenerateAsync(
            TransformationContext context,
            IProgress<Diagnostic> progress,
            CancellationToken cancellationToken)
        {
            if (attributeData.ConstructorArguments.Any(arg => arg.Value.ToString() == "warn"))
            {
                progress.Report(Diagnostic.Create(WarnDescriptor, context.ProcessingNode.GetLocation()));
            }
            if (attributeData.ConstructorArguments.Any(arg => arg.Value.ToString() == "error"))
            {
                progress.Report(Diagnostic.Create(ErrorDescriptor, context.ProcessingNode.GetLocation()));
            }
            if (attributeData.ConstructorArguments.Any(arg => arg.Value.ToString() == "throw"))
            {
                throw new InvalidOperationException("Custom exception message");
            }
            var prop = SyntaxFactory.ParseMemberDeclaration("public int Bugger { get; }");
            return Task.FromResult(SyntaxFactory.List<MemberDeclarationSyntax>(new []{ prop }));
        }
    }
}

To create attribute:

    [CodeGenerationAttribute("BuggedGenerator.ErrorGenerator, BuggedGenerator")]
    class ErrorGenAttribute : Attribute
    {
        public ErrorGenAttribute(string action = null)
        {
        }
    }