Re: [PATCH v2] completion: zsh: support completion after "git -C <path>"

[Junio C Hamano <gitster@pobox.com>]

"D. Ben Knoble" <ben.knoble@gmail.com> writes:

>>      ++                         ;;
>>      ++                 -c|--git-dir|--work-tree|--namespace)
>>      ++                         (( i++ ))
>>      ++                         ;;
>>      ++                 -*)
>>      ++                         ;;
>
> Yep, unlike Bash (which requires at least one command in the "list"
> part between a pattern and the terminator), Zsh accepts empty actions
> here.

This may be a common misconception.

It is true that a compound_list is not allowed to be empty, but
POSIX.1 sh grammar [*] explicitly allows ';;' to come after ')'
without a compound_list in between.

Specifically

        case_item        :     pattern ')' linebreak     DSEMI linebreak
                         |     pattern ')' compound_list DSEMI linebreak
                         | '(' pattern ')' linebreak     DSEMI linebreak
                         | '(' pattern ')' compound_list DSEMI linebreak
                         ;

where "linebreak" is a run of NEWLINE tokens or empty.  So

	case $foo in
	bar) ;;
	esac

is allowed.


[Footnote]

* Look for case_clause in
  https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html
  and read from there.