Re: [PATCH 2/2] help --standard: list standard commands

> If you run "make" on a branch that adds "git check-ignore", checkout
> an older branch that did not know about the command without "make clean",
> and the run t9902 test, the completion script fails to exclude the
> "check-ignore" command from candidates to complete "check".
> 
> This is because the completion script asks "git help -a" to show
> every executable that begins with "git-" in the GIT_EXEC_PATH, and
> because we run tests with GIT_EXEC_PATH set to the top of the
> working tree, that has the executable we just built, in order to
> test these before installing.  Leftover "git check-ignore" that we
> did not build for the current version gets in the way.
> 
> One way to solve this is to restrict the completion to only the
> commands we know about.
> 
> Note that this will make the completion useless in real life for
> some people, as they do want to get their custom commands on their
> $PATH to be included in the completion.
> 
> Signed-off-by: Junio C Hamano <gitster@pobox.com>
> ---
> 
>  * This is not a real patch, for the reasons stated.
> 
>  builtin/help.c                         | 17 ++++++++++++++---
>  command-list.txt                       |  4 ++--
>  contrib/completion/git-completion.bash | 14 +-------------
>  generate-cmdlist.sh                    | 13 ++++++++++++-
>  help.c                                 | 30 ++++++++++++++++++++++++++++--
>  help.h                                 |  1 +
>  6 files changed, 58 insertions(+), 21 deletions(-)
> 
> diff --git a/builtin/help.c b/builtin/help.c
> index 6067a61..32e7d64 100644
> --- a/builtin/help.c
> +++ b/builtin/help.c
> @@ -35,11 +35,16 @@ enum help_format {
> 
>  static const char *html_path;
> 
> -static int show_all = 0;
> +#define HELP_SHOW_ALL 1
> +#define HELP_SHOW_STANDARD 2
> +static int show_what;
>  static unsigned int colopts;
>  static enum help_format help_format = HELP_FORMAT_NONE;
>  static struct option builtin_help_options[] = {
> -	OPT_BOOLEAN('a', "all", &show_all, N_("print all available commands")),
> +	OPT_SET_INT('a', "all", &show_what, N_("print all available commands"),
> +		HELP_SHOW_ALL),
> +	OPT_SET_INT(0, "standard", &show_what, N_("print all available
> commands"), +		HELP_SHOW_STANDARD),
>  	OPT_SET_INT('m', "man", &help_format, N_("show man page"),
> HELP_FORMAT_MAN), OPT_SET_INT('w', "web", &help_format, N_("show manual in
> web browser"), HELP_FORMAT_WEB),
> @@ -424,12 +429,18 @@ int cmd_help(int argc, const char **argv, const char
> *prefix) builtin_help_usage, 0);
>  	parsed_help_format = help_format;
> 
> -	if (show_all) {
> +	if (show_what == HELP_SHOW_ALL) {
>  		git_config(git_help_config, NULL);
>  		printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
>  		list_commands(colopts, &main_cmds, &other_cmds);
>  		printf("%s\n", _(git_more_info_string));
>  		return 0;
> +	} else if (show_what == HELP_SHOW_STANDARD) {
> +		int i;
> +		limit_to_standard(&main_cmds);
> +		for (i = 0; i < main_cmds.cnt; i++)
> +			printf("%s\n", main_cmds.names[i]->name);
> +		return 0;
>  	}
> 
>  	if (!argv[0]) {
> diff --git a/command-list.txt b/command-list.txt
> index 7e8cfec..94ce8ec 100644
> --- a/command-list.txt
> +++ b/command-list.txt
> @@ -116,8 +116,8 @@ git-show                                mainporcelain
> common git-show-branch                         ancillaryinterrogators
>  git-show-index                          plumbinginterrogators
>  git-show-ref                            plumbinginterrogators
> -git-sh-i18n                             purehelpers
> -git-sh-setup                            purehelpers
> +git-sh-i18n                             purehelpers nocomplete
> +git-sh-setup                            purehelpers nocomplete
>  git-stash                               mainporcelain
>  git-status                              mainporcelain common
>  git-stripspace                          purehelpers
> diff --git a/contrib/completion/git-completion.bash
> b/contrib/completion/git-completion.bash index a4c48e1..46f22af 100644
> --- a/contrib/completion/git-completion.bash
> +++ b/contrib/completion/git-completion.bash
> @@ -531,23 +531,11 @@ __git_complete_strategy ()
>  	return 1
>  }
> 
> -__git_list_all_commands ()
> -{
> -	local i IFS=" "$'\n'
> -	for i in $(git help -a|egrep '^  [a-zA-Z0-9]')
> -	do
> -		case $i in
> -		*--*)             : helper pattern;;
> -		*) echo $i;;
> -		esac
> -	done
> -}
> -
>  __git_all_commands=
>  __git_compute_all_commands ()
>  {
>  	test -n "$__git_all_commands" ||
> -	__git_all_commands=$(__git_list_all_commands)
> +	__git_all_commands=$(git help --standard)
>  }
> 
>  __git_list_porcelain_commands ()
> diff --git a/generate-cmdlist.sh b/generate-cmdlist.sh
> index 9a4c9b9..7800af3 100755
> --- a/generate-cmdlist.sh
> +++ b/generate-cmdlist.sh
> @@ -9,7 +9,7 @@ struct cmdname_help {
>  static struct cmdname_help common_cmds[] = {"
> 
>  sed -n -e 's/^git-\([^ 	]*\)[ 	].* common.*/\1/p' command-list.txt |
> -sort |
> +LC_ALL=C LANG=C sort |
>  while read cmd
>  do
>       sed -n '
> @@ -20,4 +20,15 @@ do
>  	    p
>       }' "Documentation/git-$cmd.txt"
>  done
> +echo "};
> +
> +static const char *standard_cmd[] = {"
> +
> +LC_ALL=C LANG=C sort command-list.txt |
> +sed -n -e '
> +	/^git-[^ 	]*[ 	].* deprecated.*/d
> +	/^git-[^ 	]*[ 	].* nocomplete.*/d
> +	s/^git-\([^ 	]*\)[ 	].*/  "\1",/p
> +'
> +
>  echo "};"
> diff --git a/help.c b/help.c
> index 1dfa0b0..2ad10db 100644
> --- a/help.c
> +++ b/help.c
> @@ -182,7 +182,7 @@ void load_command_list(const char *prefix,
>  		uniq(main_cmds);
>  	}
> 
> -	if (env_path) {
> +	if (env_path && other_cmds) {
>  		char *paths, *path, *colon;
>  		path = paths = xstrdup(env_path);
>  		while (1) {
> @@ -201,7 +201,33 @@ void load_command_list(const char *prefix,
>  		      sizeof(*other_cmds->names), cmdname_compare);
>  		uniq(other_cmds);
>  	}
> -	exclude_cmds(other_cmds, main_cmds);
> +
> +	if (other_cmds)
> +		exclude_cmds(other_cmds, main_cmds);
> +}
> +
> +void limit_to_standard(struct cmdnames *cmds)
> +{
> +	int src = 0, dst = 0, ref = 0;
> +
> +	while (src < cmds->cnt && ref < ARRAY_SIZE(standard_cmd)) {
> +		int cmp = strcmp(cmds->names[src]->name, standard_cmd[ref]);
> +		if (cmp < 0) {
> +			src++; /* not a standard command */
> +		} else if (!cmp) {
> +			if (dst != src) {
> +				free(cmds->names[dst]);
> +				cmds->names[dst] = cmds->names[src];
> +			}
> +			ref++;
> +			dst++;
> +		} else {
> +			ref++; /* uninstalled standard command */
> +		}
> +	}
> +	for (src = dst; src < cmds->cnt; src++)
> +		free(cmds->names[src]);
> +	cmds->cnt = dst;
>  }
> 
>  void list_commands(unsigned int colopts,
> diff --git a/help.h b/help.h
> index 0ae5a12..ce0d2a5 100644
> --- a/help.h
> +++ b/help.h
> @@ -21,6 +21,7 @@ extern const char *help_unknown_cmd(const char *cmd);
>  extern void load_command_list(const char *prefix,
>  			      struct cmdnames *main_cmds,
>  			      struct cmdnames *other_cmds);
> +extern void limit_to_standard(struct cmdnames *);
>  extern void add_cmdname(struct cmdnames *cmds, const char *name, int len);
>  /* Here we require that excludes is a sorted list. */
>  extern void exclude_cmds(struct cmdnames *cmds, struct cmdnames
> *excludes);