public static async Task VerifyAnalyzerAsync(
     string source,
     params DiagnosticResult[] expected)
 {
     var test = new AnalyzerTest(source, expected);
     await test.RunAsync(CancellationToken.None);
 }
 public static async Task VerifyAnalyzerAsync(
     string source,
     IEnumerable <Assembly> additionalReferences,
     params DiagnosticResult[] expected)
 {
     var test = new AnalyzerTest(source, additionalReferences, expected);
     await test.RunAsync(CancellationToken.None);
 }