public static Diagnostic Format(TextSpan textSpan, DiagnosticId diagnosticId, params object[] args)
{
var message = diagnosticId.GetMessage();
var formattedMessage = (message != null)
? string.Format(CultureInfo.CurrentCulture, message, args)
: $"Missing diagnostic message for {diagnosticId}";
return new Diagnostic(textSpan, diagnosticId, formattedMessage);
}
}