docs: public List<File> resolve(Request request) {
          List<File> result;
          String actual;
          boolean variantSeen;
  
          result = new ArrayList<File>();
          variantSeen = false;
          for (File file : files) {
              if (file.getType().equals(request.type)) {
                  actual = file.getVariant();
                  if (actual == null) {
                      result.add(file);
                  } else {
                      variantSeen = true;
                  }
              }
          }
          if (variantSeen) {
              addVariant(request.type, getBest(request.type, request.variant), result);
          }
          return result;
      }