Merge branch 'sg/parse-options-subcommand'

Introduce the "subcommand" mode to parse-options API and update the
command line parser of Git commands with subcommands.

* sg/parse-options-subcommand: (23 commits)
  remote: run "remote rm" argv through parse_options()
  maintenance: add parse-options boilerplate for subcommands
  pass subcommand "prefix" arguments to parse_options()
  builtin/worktree.c: let parse-options parse subcommands
  builtin/stash.c: let parse-options parse subcommands
  builtin/sparse-checkout.c: let parse-options parse subcommands
  builtin/remote.c: let parse-options parse subcommands
  builtin/reflog.c: let parse-options parse subcommands
  builtin/notes.c: let parse-options parse subcommands
  builtin/multi-pack-index.c: let parse-options parse subcommands
  builtin/hook.c: let parse-options parse subcommands
  builtin/gc.c: let parse-options parse 'git maintenance's subcommands
  builtin/commit-graph.c: let parse-options parse subcommands
  builtin/bundle.c: let parse-options parse subcommands
  parse-options: add support for parsing subcommands
  parse-options: drop leading space from '--git-completion-helper' output
  parse-options: clarify the limitations of PARSE_OPT_NODASH
  parse-options: PARSE_OPT_KEEP_UNKNOWN only applies to --options
  api-parse-options.txt: fix description of OPT_CMDMODE
  t0040-parse-options: test parse_options() with various 'parse_opt_flags'
  ...

4 files changed, 132 insertions, 1 deletions

diff --git a/t/helper/test-parse-options.c b/t/helper/test-parse-options.c
index 48d3cf6692..aa0ad45851 100644
--- a/t/helper/test-parse-options.c
+++ b/t/helper/test-parse-options.c
@@ -192,3 +192,130 @@ int cmd__parse_options(int argc, const char **argv)
 
 	return ret;
 }
+
+static void print_args(int argc, const char **argv)
+{
+	for (int i = 0; i < argc; i++)
+		printf("arg %02d: %s\n", i, argv[i]);
+}
+
+static int parse_options_flags__cmd(int argc, const char **argv,
+				    enum parse_opt_flags test_flags)
+{
+	const char *usage[] = {
+		"<...> cmd [options]",
+		NULL
+	};
+	int opt = 0;
+	const struct option options[] = {
+		OPT_INTEGER('o', "opt", &opt, "an integer option"),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, NULL, options, usage, test_flags);
+
+	printf("opt: %d\n", opt);
+	print_args(argc, argv);
+
+	return 0;
+}
+
+static enum parse_opt_flags test_flags = 0;
+static const struct option test_flag_options[] = {
+	OPT_GROUP("flag-options:"),
+	OPT_BIT(0, "keep-dashdash", &test_flags,
+		"pass PARSE_OPT_KEEP_DASHDASH to parse_options()",
+		PARSE_OPT_KEEP_DASHDASH),
+	OPT_BIT(0, "stop-at-non-option", &test_flags,
+		"pass PARSE_OPT_STOP_AT_NON_OPTION to parse_options()",
+		PARSE_OPT_STOP_AT_NON_OPTION),
+	OPT_BIT(0, "keep-argv0", &test_flags,
+		"pass PARSE_OPT_KEEP_ARGV0 to parse_options()",
+		PARSE_OPT_KEEP_ARGV0),
+	OPT_BIT(0, "keep-unknown-opt", &test_flags,
+		"pass PARSE_OPT_KEEP_UNKNOWN_OPT to parse_options()",
+		PARSE_OPT_KEEP_UNKNOWN_OPT),
+	OPT_BIT(0, "no-internal-help", &test_flags,
+		"pass PARSE_OPT_NO_INTERNAL_HELP to parse_options()",
+		PARSE_OPT_NO_INTERNAL_HELP),
+	OPT_BIT(0, "subcommand-optional", &test_flags,
+		"pass PARSE_OPT_SUBCOMMAND_OPTIONAL to parse_options()",
+		PARSE_OPT_SUBCOMMAND_OPTIONAL),
+	OPT_END()
+};
+
+int cmd__parse_options_flags(int argc, const char **argv)
+{
+	const char *usage[] = {
+		"test-tool parse-options-flags [flag-options] cmd [options]",
+		NULL
+	};
+
+	argc = parse_options(argc, argv, NULL, test_flag_options, usage,
+			     PARSE_OPT_STOP_AT_NON_OPTION);
+
+	if (argc == 0 || strcmp(argv[0], "cmd")) {
+		error("'cmd' is mandatory");
+		usage_with_options(usage, test_flag_options);
+	}
+
+	return parse_options_flags__cmd(argc, argv, test_flags);
+}
+
+static int subcmd_one(int argc, const char **argv, const char *prefix)
+{
+	printf("fn: subcmd_one\n");
+	print_args(argc, argv);
+	return 0;
+}
+
+static int subcmd_two(int argc, const char **argv, const char *prefix)
+{
+	printf("fn: subcmd_two\n");
+	print_args(argc, argv);
+	return 0;
+}
+
+static int parse_subcommand__cmd(int argc, const char **argv,
+				 enum parse_opt_flags test_flags)
+{
+	const char *usage[] = {
+		"<...> cmd subcmd-one",
+		"<...> cmd subcmd-two",
+		NULL
+	};
+	parse_opt_subcommand_fn *fn = NULL;
+	int opt = 0;
+	struct option options[] = {
+		OPT_SUBCOMMAND("subcmd-one", &fn, subcmd_one),
+		OPT_SUBCOMMAND("subcmd-two", &fn, subcmd_two),
+		OPT_INTEGER('o', "opt", &opt, "an integer option"),
+		OPT_END()
+	};
+
+	if (test_flags & PARSE_OPT_SUBCOMMAND_OPTIONAL)
+		fn = subcmd_one;
+	argc = parse_options(argc, argv, NULL, options, usage, test_flags);
+
+	printf("opt: %d\n", opt);
+
+	return fn(argc, argv, NULL);
+}
+
+int cmd__parse_subcommand(int argc, const char **argv)
+{
+	const char *usage[] = {
+		"test-tool parse-subcommand [flag-options] cmd <subcommand>",
+		NULL
+	};
+
+	argc = parse_options(argc, argv, NULL, test_flag_options, usage,
+			     PARSE_OPT_STOP_AT_NON_OPTION);
+
+	if (argc == 0 || strcmp(argv[0], "cmd")) {
+		error("'cmd' is mandatory");
+		usage_with_options(usage, test_flag_options);
+	}
+
+	return parse_subcommand__cmd(argc, argv, test_flags);
+}
diff --git a/t/helper/test-serve-v2.c b/t/helper/test-serve-v2.c
index 28e905afc3..824e5c0a95 100644
--- a/t/helper/test-serve-v2.c
+++ b/t/helper/test-serve-v2.c
@@ -24,7 +24,7 @@ int cmd__serve_v2(int argc, const char **argv)
 	/* ignore all unknown cmdline switches for now */
 	argc = parse_options(argc, argv, prefix, options, serve_usage,
 			     PARSE_OPT_KEEP_DASHDASH |
-			     PARSE_OPT_KEEP_UNKNOWN);
+			     PARSE_OPT_KEEP_UNKNOWN_OPT);
 
 	if (advertise_capabilities)
 		protocol_v2_advertise_capabilities();
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index d6a560f832..8005588679 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -51,7 +51,9 @@ static struct test_cmd cmds[] = {
 	{ "online-cpus", cmd__online_cpus },
 	{ "pack-mtimes", cmd__pack_mtimes },
 	{ "parse-options", cmd__parse_options },
+	{ "parse-options-flags", cmd__parse_options_flags },
 	{ "parse-pathspec-file", cmd__parse_pathspec_file },
+	{ "parse-subcommand", cmd__parse_subcommand },
 	{ "partial-clone", cmd__partial_clone },
 	{ "path-utils", cmd__path_utils },
 	{ "pcre2-config", cmd__pcre2_config },
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index 21a91b1019..a432cc77d9 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -41,7 +41,9 @@ int cmd__oidtree(int argc, const char **argv);
 int cmd__online_cpus(int argc, const char **argv);
 int cmd__pack_mtimes(int argc, const char **argv);
 int cmd__parse_options(int argc, const char **argv);
+int cmd__parse_options_flags(int argc, const char **argv);
 int cmd__parse_pathspec_file(int argc, const char** argv);
+int cmd__parse_subcommand(int argc, const char **argv);
 int cmd__partial_clone(int argc, const char **argv);
 int cmd__path_utils(int argc, const char **argv);
 int cmd__pcre2_config(int argc, const char **argv);