anchor.diff:      logger.stdout('Migrating ${options.directory}');
       logger.stdout('');
   
  -    if (!MigrateCommand.nullSafetyOnByDefault) {
  -      logger.stdout(MigrateCommand.preFlagFlipCaveat);
  -      logger.stdout('');
  -    }
  -
       logger.stdout(MigrateCommand.migrationGuideLink);
       logger.stdout('');
   
  
positive.code:   static const String migrationGuideLink =
        'See https://dart.dev/go/null-safety-migration for a migration guide.';
  
    static const String preFlagFlipCaveat =
        'Note: this tool is currently running on an SDK version where null '
        'safety is not yet enabled by default. You may encounter issues in the '
        'migration process - some aspects of the toolchain assume that they are '
        'running on an SDK where null safety has been enabled by default.';
  
    /// Return whether the SDK has null safety on by default.
    static bool get nullSafetyOnByDefault => IsEnabledByDefault.non_nullable;
  
  
negative.code:   /*late*/ bool _shouldDrawProgress;
  
    /// The width of the terminal, in terms of characters.
    /*late*/
    int _width;
  
    final Logger _logger;
  
    /// The inner width of the terminal, in terms of characters.
    ///
    /// This represents the number of characters available for drawing progress.
    /*late*/
    int _innerWidth;
  
    final int _totalTickCount;
  
  