public void AssignAsyncVoidLambdaToAction_TestCodeFix(string oldAssertion, string newAssertion)
        {
            var oldSource = GenerateCode.AsyncFunctionStatement(oldAssertion);
            var newSource = GenerateCode.AsyncFunctionStatement(newAssertion);

            DiagnosticVerifier.VerifyCSharpFix <AsyncVoidCodeFix, AsyncVoidAnalyzer>(oldSource, newSource);
        }
        private void VerifyCSharpFix <TCodeFixProvider, TDiagnosticAnalyzer>(string oldSourceAssertion, string newSourceAssertion)
            where TCodeFixProvider : Microsoft.CodeAnalysis.CodeFixes.CodeFixProvider, new()
            where TDiagnosticAnalyzer : Microsoft.CodeAnalysis.Diagnostics.DiagnosticAnalyzer, new()
        {
            var oldSource = GenerateCode.NumericAssertion(oldSourceAssertion);
            var newSource = GenerateCode.NumericAssertion(newSourceAssertion);

            DiagnosticVerifier.VerifyCSharpFix <TCodeFixProvider, TDiagnosticAnalyzer>(oldSource, newSource);
        }