ProxyGenerator/src/ProxyInterfaceSourceGenerator/Extensions/SymbolExtensions.cs

using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;

namespace ProxyInterfaceSourceGenerator.Extensions
{
    internal static class SymbolExtensions
    {
        public static bool IsKeywordOrReserved(this ISymbol symbol) =>
            SyntaxFacts.GetKeywordKind(symbol.Name) != SyntaxKind.None || SyntaxFacts.GetContextualKeywordKind(symbol.Name) != SyntaxKind.None;

        public static string GetSanitizedName(this ISymbol symbol) =>
            symbol.IsKeywordOrReserved() ? $"@{symbol.Name}" : symbol.Name;
    }
}