prune: introduce OPT_EXPIRY_DATE() and use it

Earlier we added support for --expire=all (or --expire=now) that
considers all crufts, regardless of their age, as eligible for
garbage collection by turning command argument parsers that use
approxidate() to use parse_expiry_date(), but "git prune" used a
built-in parse-options facility OPT_DATE() and did not benefit from
the new function.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/technical/api-parse-options.txt

@@ -176,6 +176,10 @@ There are some macros to easily define options:
 	Introduce an option with date argument, see `approxidate()`.
 	The timestamp is put into `int_var`.
 
+`OPT_EXPIRY_DATE(short, long, &int_var, description)`::
+	Introduce an option with expiry date argument, see `parse_expiry_date()`.
+	The timestamp is put into `int_var`.
+
 `OPT_CALLBACK(short, long, &var, arg_str, description, func_ptr)`::
 	Introduce an option with argument.
 	The argument will be fed into the function given by `func_ptr`

builtin/prune.c

@@ -132,8 +132,8 @@ int cmd_prune(int argc, const char **argv, const char *prefix)
 		OPT__DRY_RUN(&show_only, N_("do not remove, show only")),
 		OPT__VERBOSE(&verbose, N_("report pruned objects")),
 		OPT_BOOL(0, "progress", &show_progress, N_("show progress")),
-		OPT_DATE(0, "expire", &expire,
-			 N_("expire objects older than <time>")),
+		OPT_EXPIRY_DATE(0, "expire", &expire,
+				N_("expire objects older than <time>")),
 		OPT_END()
 	};
 	char *s;

parse-options-cb.c

@@ -33,6 +33,12 @@ int parse_opt_approxidate_cb(const struct option *opt, const char *arg,
 	return 0;
 }
 
+int parse_opt_expiry_date_cb(const struct option *opt, const char *arg,
+			     int unset)
+{
+	return parse_expiry_date(arg, (unsigned long *)opt->value);
+}
+
 int parse_opt_color_flag_cb(const struct option *opt, const char *arg,
 			    int unset)
 {

parse-options.h

@@ -140,6 +140,9 @@ struct option {
 #define OPT_DATE(s, l, v, h) \
 	{ OPTION_CALLBACK, (s), (l), (v), N_("time"),(h), 0,	\
 	  parse_opt_approxidate_cb }
+#define OPT_EXPIRY_DATE(s, l, v, h) \
+	{ OPTION_CALLBACK, (s), (l), (v), N_("expiry date"),(h), 0,	\
+	  parse_opt_expiry_date_cb }
 #define OPT_CALLBACK(s, l, v, a, h, f) \
 	{ OPTION_CALLBACK, (s), (l), (v), (a), (h), 0, (f) }
 #define OPT_NUMBER_CALLBACK(v, h, f) \
@@ -215,6 +218,7 @@ extern int parse_options_concat(struct option *dst, size_t, struct option *src);
 /*----- some often used options -----*/
 extern int parse_opt_abbrev_cb(const struct option *, const char *, int);
 extern int parse_opt_approxidate_cb(const struct option *, const char *, int);
+extern int parse_opt_expiry_date_cb(const struct option *, const char *, int);
 extern int parse_opt_color_flag_cb(const struct option *, const char *, int);
 extern int parse_opt_verbosity_cb(const struct option *, const char *, int);
 extern int parse_opt_with_commit(const struct option *, const char *, int);