save(patterns, lockfile, flags, workspaceLayout, artifacts) {
    var _this6 = this;

    return (0, (_asyncToGenerator2 || _load_asyncToGenerator()).default)(function* () {
      const integrityFile = yield _this6._generateIntegrityFile(lockfile, patterns, flags, workspaceLayout, artifacts);

      const loc = yield _this6._getIntegrityFileLocation();
      invariant(loc.locationPath, 'expected integrity hash location');

      yield (_fs || _load_fs()).mkdirp(path.dirname(loc.locationPath));
      yield (_fs || _load_fs()).writeFile(loc.locationPath, JSON.stringify(integrityFile, null, 2));
    })();
  }
Write the integrity hash of the current install to disk.