parse-opt: make PARSE_OPT_STOP_AT_NON_OPTION available to git rev-parse

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-rev-parse.txt

@@ -30,6 +30,11 @@ OPTIONS
 	Only meaningful in `--parseopt` mode. Tells the option parser to echo
 	out the first `--` met instead of skipping it.
 
+--stop-at-non-option::
+	Only meaningful in `--parseopt` mode.  Lets the option parser stop at
+	the first non-option argument.  This can be used to parse sub-commands
+	that take options themself.
+
 --sq-quote::
 	Use 'git-rev-parse' in shell quoting mode (see SQ-QUOTE
 	section below). In contrast to the `--sq` option below, this

builtin-rev-parse.c

@@ -301,14 +301,17 @@ static const char *skipspaces(const char *s)
 
 static int cmd_parseopt(int argc, const char **argv, const char *prefix)
 {
-	static int keep_dashdash = 0;
+	static int keep_dashdash = 0, stop_at_non_option = 0;
 	static char const * const parseopt_usage[] = {
 		"git rev-parse --parseopt [options] -- [<args>...]",
 		NULL
 	};
 	static struct option parseopt_opts[] = {
 		OPT_BOOLEAN(0, "keep-dashdash", &keep_dashdash,
 					"keep the `--` passed as an arg"),
+		OPT_BOOLEAN(0, "stop-at-non-option", &stop_at_non_option,
+					"stop parsing after the "
+					"first non-option argument"),
 		OPT_END(),
 	};
 
@@ -394,7 +397,8 @@ static int cmd_parseopt(int argc, const char **argv, const char *prefix)
 	ALLOC_GROW(opts, onb + 1, osz);
 	memset(opts + onb, 0, sizeof(opts[onb]));
 	argc = parse_options(argc, argv, prefix, opts, usage,
-	                     keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0);
+			keep_dashdash ? PARSE_OPT_KEEP_DASHDASH : 0 |
+			stop_at_non_option ? PARSE_OPT_STOP_AT_NON_OPTION : 0);
 
 	strbuf_addf(&parsed, " --");
 	sq_quote_argv(&parsed, argv, 0);

t/t1502-rev-parse-parseopt.sh

@@ -65,6 +65,11 @@ test_expect_success 'test --parseopt with --' '
 	test_cmp expect output
 '
 
+test_expect_success 'test --parseopt --stop-at-non-option' '
+	git rev-parse --parseopt --stop-at-non-option -- --foo arg --bar=ham < optionspec > output &&
+	test_cmp expect output
+'
+
 cat > expect <<EOF
 set -- --foo -- '--' 'arg' '--bar=ham'
 EOF