anchor.diff:  
     env.sdkRoot = args['sdk-root'];
     if (env.sdkRoot != null) {
  -    env.sdkRoot = normalize(join(absolute(env.sdkRoot), 'lib'));
  +    env.sdkRoot = p.normalize(p.join(p.absolute(env.sdkRoot), 'lib'));
       if (!FileSystemEntity.isDirectorySync(env.sdkRoot)) {
         fail('Provided SDK root "${args["sdk-root"]}" is not a valid SDK '
             'top-level directory');
  
positive.code:   }
  
    if (args['base-directory'] != null) {
      env.baseDirectory = absolute(args['base-directory']);
    }
  
    env.lcov = args['lcov'];
  
negative.code:   if (args['out'] == 'stdout') {
      env.output = stdout;
    } else {
      var outpath = p.absolute(p.normalize(args['out']));
      var outfile = new File(outpath)..createSync(recursive: true);
      env.output = outfile.openWrite();
    }
  