async Task validateContent(IDirectoryAccessor directory, string folderNames, string fileNames, System.Threading.CancellationToken cancellation)
{
var directories = directory.EnumerateDirectoriesAsync(cancellation).Select(d => d.Result.Name).ToArray();
var files = directory.EnumerateFilesAsync(cancellation).Select(f => f.Result.Name).ToArray();
var expectedFolders = folderNames?.Split(",") ?? new string[0];
var expectedFiles = fileNames?.Split(",") ?? new string[0];
Assert.Equal(expectedFolders, directories);
Assert.Equal(expectedFiles, files);
}