createEmptyManifestFolders() {
    var _this4 = this;

    return (0, (_asyncToGenerator2 || _load_asyncToGenerator()).default)(function* () {
      if (_this4.config.modulesFolder) {
        // already created
        return;
      }

      for (var _iterator9 = _this4.rootManifestRegistries, _isArray9 = Array.isArray(_iterator9), _i9 = 0, _iterator9 = _isArray9 ? _iterator9 : _iterator9[Symbol.iterator]();;) {
        var _ref10;

        if (_isArray9) {
          if (_i9 >= _iterator9.length) break;
          _ref10 = _iterator9[_i9++];
        } else {
          _i9 = _iterator9.next();
          if (_i9.done) break;
          _ref10 = _i9.value;
        }

        const registryName = _ref10;
        const folder = _this4.config.registries[registryName].folder;

        yield (_fs || _load_fs()).mkdirp(path.join(_this4.config.lockfileFolder, folder));
      }
    })();
  }
Produce empty folders for all used root manifests.