TypeConverter Error Handling

[BenMendel]

I wrote this uint TypeConverter:

internal sealed class HexUIntConverter : TypeConverter
{
    public override bool CanConvertFrom(ITypeDescriptorContext? context, Type sourceType)
        => sourceType == typeof(string) || base.CanConvertFrom(context, sourceType);

    public override object? ConvertFrom(ITypeDescriptorContext? context, CultureInfo? culture, object value)
    {
        if (value is not string str)
            return base.ConvertFrom(context, culture, value);

        culture ??= CultureInfo.CurrentCulture;

        if (str.StartsWith("0x", StringComparison.OrdinalIgnoreCase))
        {
            if (uint.TryParse(str[2..], NumberStyles.HexNumber, culture, out var hex))
            {
                return hex;
            }

            ThrowHelper.ThrowNotSupportedException($"Invalid hex uint: '{str}'.");
        }

        if (uint.TryParse(str, NumberStyles.Integer, culture, out var dec))
        {
            return dec;
        }


        throw new InvalidOperationException($"HexUIntConverter cannot convert '{str}' to uint.");
        throw new FormatException($"HexUIntConverter cannot convert '{str}' to uint.");
        return ThrowHelper.ThrowInvalidOperationException<object?>($"HexUIntConverter cannot convert '{str}' to uint.");
    }
}

As suggested in Type Converter Page, I tried throwing InvalidOperationException,
Then tried as suggested in Using Custom Type Converter, I tried throwing FormatException
Both resulted in: Error: Failed to convert '4294967296' to Nullable'1. and not with my custom exception message.

[Rekkonnect]

This should be generally improved I believe, right now even the basic type converters from the library itself are simply throwing exceptions instead of providing a helpful error message to the user. A simple command with an int option will result in the following:

Spectre.Console.Cli.CommandRuntimeException: Failed to convert 'str' to Int32.
     System.ArgumentException: str is not a valid value for Int32. (Parameter 'value')
          System.FormatException: The input string 'str' was not in a correct format.
            at void System.Number.ThrowFormatException<TChar>(ReadOnlySpan<TChar> value)
            at int System.Int32.Parse(string s, NumberStyles style, IFormatProvider provider)
            at object System.ComponentModel.Int32Converter.FromString(string value, NumberFormatInfo formatInfo)
            at object System.ComponentModel.BaseNumberConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
       at object System.ComponentModel.BaseNumberConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
       at object Spectre.Console.Cli.CommandValueResolver.SmartConverter.ConvertFrom(object input) in CommandValueResolver.cs:215
       at CommandValueLookup Spectre.Console.Cli.CommandValueResolver.GetParameterValues(CommandTree tree, ITypeResolver resolver) in CommandValueResolver.cs:86
  at CommandValueLookup Spectre.Console.Cli.CommandValueResolver.GetParameterValues(CommandTree tree, ITypeResolver resolver) in CommandValueResolver.cs:90
  at CommandSettings Spectre.Console.Cli.CommandBinder.Bind(CommandTree tree, Type settingsType, ITypeResolver resolver) in CommandBinder.cs:7
  at async Task<int> Spectre.Console.Cli.CommandExecutor.ExecuteAsync(CommandTree leaf, CommandTree tree, CommandContext context, ITypeResolver resolver, IConfiguration configuration, CancellationToken cancellationToken
     ) in CommandExecutor.cs:236