anchor.diff:      ArgResults options, {
       IncrementalKernelGenerator generator,
     }) async {
  -    _filename = filename;
  +    final Uri _filenameUri = Uri.base.resolve(new Uri.file(filename).toString());
       _kernelBinaryFilename = "$filename.dill";
       final String boundaryKey = new Uuid().generateV4();
       _outputStream.writeln("result $boundaryKey");
  
positive.code:   BinaryPrinterFactory printerFactory;
  
    IncrementalKernelGenerator _generator;
    String _filename;
    String _kernelBinaryFilename;
  
    @override
  
negative.code:   }
  
    Uri _ensureFolderPath(String path) {
      String uriPath = new Uri.file(path).toString();
      if (!uriPath.endsWith('/')) {
        uriPath = '$uriPath/';
      }
      return Uri.base.resolve(uriPath);
    }
  
    /// Runs the given function [f] in a Zone that redirects all prints into
  