Re: [PATCH] push: unset PARSE_OPT_OPTARG for --recurse-submodules

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

Junio C Hamano <gitster@pobox.com> writes:

> Jeff King <peff@peff.net> writes:
>
>>> @@ -554,7 +552,7 @@ int cmd_push(int argc, const char **argv, const char *prefix)
>>>  		  PARSE_OPT_OPTARG | PARSE_OPT_LITERAL_ARGHELP, parseopt_push_cas_option },
>>>  		{ OPTION_CALLBACK, 0, "recurse-submodules", &recurse_submodules, "(check|on-demand|no)",
>>>  			N_("control recursive pushing of submodules"),
>>> -			PARSE_OPT_OPTARG, option_parse_recurse_submodules },
>>> +			0, option_parse_recurse_submodules },
>>
>> This could collapse down to OPT_CALLBACK() now, though I don't think
>> it's a big deal either way.
>
> I would prefer to see OPT_CALLBACK() used; it would send a strong
> signal that this place is using the canned bog-standard and boring
> pattern, and nothing fancy is going on.

Here is what I am going to queue for this fix; hopefully it can be
cherry-picked by folks who maintain older versions of Git for
distros and in-house use.

The other "huge" patch has also been adjusted by dropping the first
hunk on builtin/push.c from it, and then resurrecting the part to
use OPT_CALLBACK_F() for compare-and-swap (which happened to be in
the same hunk).

Thanks for the fix and clean-up.  Very much appreciated.

-- >8 --
From: Denton Liu <liu.denton@gmail.com>
Date: Mon, 27 Apr 2020 02:44:08 -0400
Subject: [PATCH] push: unset PARSE_OPT_OPTARG for --recurse-submodules

When the usage for `git push` is shown, it includes the following
lines

	--recurse-submodules[=(check|on-demand|no)]
			      control recursive pushing of submodules

which seem to indicate that the argument for --recurse-submodules is
optional. However, we cannot actually run that optiion without an
argument:

	$ git push --recurse-submodules
	fatal: recurse-submodules missing parameter

Unset PARSE_OPT_OPTARG so that it is clear that this option requires an
argument. Since the parse-options machinery guarantees that an argument
is present now, assume that `arg` is set in the else of
option_parse_recurse_submodules().

Reported-by: Andrew White <andrew.white@audinate.com>
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin/push.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/builtin/push.c b/builtin/push.c
index 6dbf0f0bb7..208c2540e9 100644
--- a/builtin/push.c
+++ b/builtin/push.c
@@ -434,10 +434,8 @@ static int option_parse_recurse_submodules(const struct option *opt,
 
 	if (unset)
 		*recurse_submodules = RECURSE_SUBMODULES_OFF;
-	else if (arg)
-		*recurse_submodules = parse_push_recurse_submodules_arg(opt->long_name, arg);
 	else
-		die("%s missing parameter", opt->long_name);
+		*recurse_submodules = parse_push_recurse_submodules_arg(opt->long_name, arg);
 
 	return 0;
 }
@@ -552,9 +550,8 @@ int cmd_push(int argc, const char **argv, const char *prefix)
 		  0, CAS_OPT_NAME, &cas, N_("<refname>:<expect>"),
 		  N_("require old value of ref to be at this value"),
 		  PARSE_OPT_OPTARG | PARSE_OPT_LITERAL_ARGHELP, parseopt_push_cas_option },
-		{ OPTION_CALLBACK, 0, "recurse-submodules", &recurse_submodules, "(check|on-demand|no)",
-			N_("control recursive pushing of submodules"),
-			PARSE_OPT_OPTARG, option_parse_recurse_submodules },
+		OPT_CALLBACK(0, "recurse-submodules", &recurse_submodules, "(check|on-demand|no)",
+			     N_("control recursive pushing of submodules"), option_parse_recurse_submodules),
 		OPT_BOOL_F( 0 , "thin", &thin, N_("use thin pack"), PARSE_OPT_NOCOMPLETE),
 		OPT_STRING( 0 , "receive-pack", &receivepack, "receive-pack", N_("receive pack program")),
 		OPT_STRING( 0 , "exec", &receivepack, "receive-pack", N_("receive pack program")),
-- 
2.26.2-266-ge870325ee8