code: func (rc *refCommits) pop() (commit *gitpb.Commit, empty bool) {
  	commit, rc.commits = rc.commits[0], rc.commits[1:]
  	return commit, len(rc.commits) == 0
  }
docs: // The pop method removes and returns first commit. Second return value is true
  // if this was the last commit. Caller must ensure refCommits has commits when
  // calling the method.