anchor.diff:      tmpDir.createSync();
       
       List contents = tmpDir.listSync();
  -    List<String> nicknames; 
  +    List<String> nicknames = []; 
  +    
       for(var fileOrDir in contents) {
         if (fileOrDir is File) {
  -        nicknames.add(fileOrDir.toString());
  +        nicknames.add(path.basename(fileOrDir.path));
         } else if (fileOrDir is Directory) {
           continue;
  -      }
  -        
  +      }        
       }
  +    
       return new JSONResponse(nicknames);
     }
     shelf.Response Upload(shelf.Request req){
  
positive.code: class RegularRenter implements Renter{
    shelf.Response Download(shelf.Request req){
      var nickname = req.url.queryParameters["nickname"];
      var source = req.url.queryParameters["source"];
      print('$source, $nickname');
      
  
      return new SuccessResponse();
  
negative.code: import "dart:convert";
  import 'package:shelf/shelf.dart' as shelf;
  import 'package:shelf/shelf_io.dart' as io;
  import 'package:path/path.dart' as path;
  
  import 'response.dart';
  
  