code: function isRemote(db) {
    if (typeof db._remote === 'boolean') {
      return db._remote;
    }
    /* istanbul ignore next */
    if (typeof db.type === 'function') {
      guardedConsole('warn',
        'db.type() is deprecated and will be removed in ' +
        'a future version of PouchDB');
      return db.type() === 'http';
    }
    /* istanbul ignore next */
    return false;
  }
docs: Checks if a PouchDB object is "remote" or not. This is designed to opt-in to certain optimizations, such as avoiding checks for "dependentDbs" and other things that we know only apply to local databases. In general, "remote" should be true for the http adapter, and for third-party adapters with similar expensive boundaries to cross for every API call, such as socket-pouch and worker-pouch. Previously, this was handled via db.type() === 'http' which is now deprecated.