anchor.diff:  
     @override
     String readAsStringSync() {
  +    _throwIfWindowsDeviceDriver();
       try {
         return FileBasedSource.fileReadMode(_file.readAsStringSync());
       } on io.FileSystemException catch (exception) {
  
positive.code: 
    @override
    String toString() => path;
  }
  
  /**
  
negative.code: 
    @override
    List<int> readAsBytesSync() {
      _throwIfWindowsDeviceDriver();
      try {
        return _file.readAsBytesSync();
      } on io.FileSystemException catch (exception) {
  