private DeveloperExceptionPageMiddleware GetErrorPageMiddleware(
            IFileProvider fileProvider = null, int sourceCodeLineCount = 6)
        {
            var errorPageOptions = new ErrorPageOptions();

            errorPageOptions.SourceCodeLineCount = sourceCodeLineCount;

            if (fileProvider != null)
            {
                errorPageOptions.FileProvider = fileProvider;
            }

            var middleware = new DeveloperExceptionPageMiddleware(
                (httpContext) => { return(Task.FromResult(0)); },
                errorPageOptions,
                new LoggerFactory(),
                new TestApplicationEnvironment());

            return(middleware);
        }
        private DeveloperExceptionPageMiddleware GetErrorPageMiddleware(
            IFileProvider fileProvider = null, int sourceCodeLineCount = 6)
        {
            var errorPageOptions = new ErrorPageOptions();
            errorPageOptions.SourceCodeLineCount = sourceCodeLineCount;

            if (fileProvider != null)
            {
                errorPageOptions.FileProvider = fileProvider;
            }

            var middleware = new DeveloperExceptionPageMiddleware(
                (httpContext) => { return Task.FromResult(0); },
                errorPageOptions,
                new LoggerFactory(),
                new TestApplicationEnvironment(),
                new DiagnosticListener("Microsoft.Aspnet"));

            return middleware;
        }