Re: [PATCH 1/3] tag: use skip_prefix instead of magic numbers

On Fri, 2014-07-11 at 15:44 -0700, Junio C Hamano wrote:

Jacob Keller [off-list ref] writes:

quoted

From: Jeff King <redacted>

Make the parsing of the --sort parameter more readable by having
skip_prefix keep our pointer up to date.

Signed-off-by: Jeff King <redacted>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 builtin/tag.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/builtin/tag.c b/builtin/tag.c
index ef765563388c..7ccb6f3c581b 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c

@@ -524,18 +524,12 @@ static int parse_opt_sort(const struct option *opt, const char *arg, int unset)
 	int *sort = opt->value;
 	int flags = 0;
 
-	if (*arg == '-') {
+	if (skip_prefix(arg, "-", &arg))
 		flags |= REVERSE_SORT;
-		arg++;
-	}
-	if (starts_with(arg, "version:")) {
+
+	if (skip_prefix(arg, "version:", &arg) || skip_prefix(arg, "v:", &arg))
 		*sort = VERCMP_SORT;
-		arg += 8;
-	} else if (starts_with(arg, "v:")) {
-		*sort = VERCMP_SORT;
-		arg += 2;
-	} else
-		*sort = STRCMP_SORT;
+

By losing "*sort = STRCMP_SORT", the version after this patch would
stop clearing what is pointed by opt->value, so

	git tag --sort=v:refname --sort=refname

would no longer implement the "last one wins" semantics, no?

Am I misreading the patch?  I somehow thought Peff's original was
clearing the variable...

quoted

 	if (strcmp(arg, "refname"))
 		die(_("unsupported sort specification %s"), arg);
 	*sort |= flags;

Indeed. My patch fixes this up but I will re-work this so we don't
introduce an inbetween bug :)

Thanks,
Jake