code: func (r *Repository) Fetch(o *FetchOptions) error {
  	return r.FetchContext(context.Background(), o)
  }
docs: // Fetch fetches references along with the objects necessary to complete
  // their histories, from the remote named as FetchOptions.RemoteName.
  //
  // Returns nil if the operation is successful, NoErrAlreadyUpToDate if there are
  // no changes to be fetched, or an error.