code: func (s *SubmoduleStatus) String() string {
  	var extra string
  	var status = ' '
  
  	if s.Current.IsZero() {
  		status = '-'
  	} else if !s.IsClean() {
  		status = '+'
  	}
  
  	if len(s.Branch) != 0 {
  		extra = string(s.Branch[5:])
  	} else if !s.Current.IsZero() {
  		extra = s.Current.String()[:7]
  	}
  
  	if extra != "" {
  		extra = fmt.Sprintf(" (%s)", extra)
  	}
  
  	return fmt.Sprintf("%c%s %s%s", status, s.Expected, s.Path, extra)
  }
docs: // String is equivalent to `git submodule status <submodule>`
  //
  // This will print the SHA-1 of the currently checked out commit for a
  // submodule, along with the submodule path and the output of git describe fo
  // the SHA-1. Each SHA-1 will be prefixed with - if the submodule is not
  // initialized, + if the currently checked out submodule commit does not match
  // the SHA-1 found in the index of the containing repository.