parse-options: support --git-completion-helper

This option is designed to be used by git-completion.bash. For many
simple cases, what we do in there is usually

    __gitcomp "lots of completion options"

which has to be manually updated when a new user-visible option is
added. With support from parse-options, we can write

    __gitcomp "$(git command --git-completion-helper)"

and get that list directly from the parser for free. Dangerous/Unpopular
options could be hidden with the new "NOCOMPLETE" flag.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Nguyễn Thái Ngọc Duy 2018-02-09 18:01:40 +07:00 committed by Junio C Hamano
parent 5be1f00a9a
commit b9d7f4b4db
2 changed files with 48 additions and 1 deletions

View File

@ -425,6 +425,46 @@ void parse_options_start(struct parse_opt_ctx_t *ctx,
parse_options_check(options);
}
/*
* TODO: we are not completing the --no-XXX form yet because there are
* many options that do not suppress it properly.
*/
static int show_gitcomp(struct parse_opt_ctx_t *ctx,
const struct option *opts)
{
for (; opts->type != OPTION_END; opts++) {
const char *suffix = "";
if (!opts->long_name)
continue;
if (opts->flags & (PARSE_OPT_HIDDEN | PARSE_OPT_NOCOMPLETE))
continue;
switch (opts->type) {
case OPTION_GROUP:
continue;
case OPTION_STRING:
case OPTION_FILENAME:
case OPTION_INTEGER:
case OPTION_MAGNITUDE:
case OPTION_CALLBACK:
if (opts->flags & PARSE_OPT_NOARG)
break;
if (opts->flags & PARSE_OPT_OPTARG)
break;
if (opts->flags & PARSE_OPT_LASTARG_DEFAULT)
break;
suffix = "=";
break;
default:
break;
}
printf(" --%s%s", opts->long_name, suffix);
}
fputc('\n', stdout);
exit(0);
}
static int usage_with_options_internal(struct parse_opt_ctx_t *,
const char * const *,
const struct option *, int, int);
@ -455,6 +495,10 @@ int parse_options_step(struct parse_opt_ctx_t *ctx,
if (internal_help && ctx->total == 1 && !strcmp(arg + 1, "h"))
goto show_usage;
/* lone --git-completion-helper is asked by git-completion.bash */
if (ctx->total == 1 && !strcmp(arg + 1, "-git-completion-helper"))
return show_gitcomp(ctx, options);
if (arg[1] != '-') {
ctx->opt = arg + 1;
switch (parse_short_opt(ctx, options)) {

View File

@ -38,7 +38,8 @@ enum parse_opt_option_flags {
PARSE_OPT_LASTARG_DEFAULT = 16,
PARSE_OPT_NODASH = 32,
PARSE_OPT_LITERAL_ARGHELP = 64,
PARSE_OPT_SHELL_EVAL = 256
PARSE_OPT_SHELL_EVAL = 256,
PARSE_OPT_NOCOMPLETE = 512
};
struct option;
@ -89,6 +90,8 @@ typedef int parse_opt_ll_cb(struct parse_opt_ctx_t *ctx,
* PARSE_OPT_LITERAL_ARGHELP: says that argh shouldn't be enclosed in brackets
* (i.e. '<argh>') in the help message.
* Useful for options with multiple parameters.
* PARSE_OPT_NOCOMPLETE: by default all visible options are completable
* by git-completion.bash. This option suppresses that.
*
* `callback`::
* pointer to the callback to use for OPTION_CALLBACK or