public BackupExistsValidator(
     BackupSettings backupSettings, 
     FileSystem fileSystem, 
     BackupFileDatesQuery backupFileDatesQuery, 
     CurrentDateProvider currentDateProvider)
 {
     _backupSettings = backupSettings;
     _fileSystem = fileSystem;
     _backupFileDatesQuery = backupFileDatesQuery;
     _currentDateProvider = currentDateProvider;
 }
 public void Setup()
 {
     _fileSystem = A.Fake<FileSystem>();
     _backupFileDatesQuery = A.Fake<BackupFileDatesQuery>();
     _currentDateProvider = A.Fake<CurrentDateProvider>();
 }