public static DiagnosticResult Diagnostic(DiagnosticDescriptor descriptor)
 => CSharpCodeFixVerifier <TAnalyzer, TCodeFix, XUnitVerifier> .Diagnostic(descriptor);
 public static DiagnosticResult Diagnostic(string diagnosticId)
 => CSharpCodeFixVerifier <TAnalyzer, TCodeFix, XUnitVerifier> .Diagnostic(diagnosticId);