Re: [PATCH 2/2] parse-options.c: use "enum parse_opt_result" for parse_nodash_opt()

On Tue, Nov 09 2021, Junio C Hamano wrote:

Ævar Arnfjörð Bjarmason  [off-list ref] writes:

quoted

Change the parse_nodash_opt() function to use "enum
parse_opt_result". In 352e761388b (parse-options.[ch]: consistently
use "enum parse_opt_result", 2021-10-08) its only caller
parse_options_step() started using that return type, and the
get_value() which will be called and return from it uses the same
enum.

Let's do the same here so that this function always returns an "enum
parse_opt_result" value.

Signed-off-by: Ævar Arnfjörð Bjarmason <redacted>
---
 parse-options.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/parse-options.c b/parse-options.c
index fc5b43ff0b2..629e7963497 100644
--- a/parse-options.c
+++ b/parse-options.c

@@ -404,8 +404,9 @@ static enum parse_opt_result parse_long_opt(
 	return PARSE_OPT_UNKNOWN;
 }
 
-static int parse_nodash_opt(struct parse_opt_ctx_t *p, const char *arg,
-			    const struct option *options)
+static enum parse_opt_result parse_nodash_opt(struct parse_opt_ctx_t *p,
+					      const char *arg,
+					      const struct option *options)
 {
 	const struct option *all_opts = options;
 

@@ -415,7 +416,7 @@ static int parse_nodash_opt(struct parse_opt_ctx_t *p, const char *arg,
 		if (options->short_name == arg[0] && arg[1] == '\0')
 			return get_value(p, options, all_opts, OPT_SHORT);
 	}
-	return -2;
+	return PARSE_OPT_ERROR;
 }

The current caller only checks to skip a token that yields 0 (aka
PARSE_OPT_DONE) and does not distinguish between other values, so
this won't change the behaviour of the current code, but it is 
not clear if returning -1 (aka PARSE_OPT_ERROR) is better than -2
(aka PARSE_OPT_HELP).

I think PARSE_OPT_ERROR is probably better.

It looks like the -2 return value might have been somewhat blindly
copy/pasted between 07fe54db3cd (parse-opt: do not print errors on
unknown options, return -2 intead., 2008-06-23) and 51a9949eda7
(parseopt: add PARSE_OPT_NODASH, 2009-05-07).

I.e. we use the full enum values for the code in the former, but in the
latter we're just looking for "not zero", so error/-1 seemed like a
better fit.