[PATCH] notes: attach help text to subcommands

@@ -20,18 +20,7 @@
 #include "notes-merge.h"
 
 static const char * const git_notes_usage[] = {
-	"git notes [--ref <notes_ref>] [list [<object>]]",
-	"git notes [--ref <notes_ref>] add [-f] [-m <msg> | -F <file> | (-c | -C) <object>] [<object>]",
-	"git notes [--ref <notes_ref>] copy [-f] <from-object> <to-object>",
-	"git notes [--ref <notes_ref>] append [-m <msg> | -F <file> | (-c | -C) <object>] [<object>]",
-	"git notes [--ref <notes_ref>] edit [<object>]",
-	"git notes [--ref <notes_ref>] show [<object>]",
-	"git notes [--ref <notes_ref>] merge [-v | -q] [-s <strategy> ] <notes_ref>",
-	"git notes merge --commit [-v | -q]",
-	"git notes merge --abort [-v | -q]",
-	"git notes [--ref <notes_ref>] remove [<object>...]",
-	"git notes [--ref <notes_ref>] prune [-n | -v]",
-	"git notes [--ref <notes_ref>] get-ref",
+	"git notes [<options>] [<subcommand>] [<options>] [<object>..]",
 	NULL
 };
 

@@ -1059,15 +1048,76 @@ static int get_ref(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+
+struct subcommand {
+	const char *name;
+	const char *help;
+	int (*callback)(int, const char **, const char *);
+};
+
+#define USAGE_OPTS_WIDTH 24
+#define USAGE_GAP         2
+
+static void subcommand_usage(const char * const *usagestr,
+			struct string_list *subcmds)
+{
+	int i;
+
+	fprintf(stderr, "usage: %s\n", *usagestr++);
+	while (*usagestr && **usagestr)
+		fprintf(stderr, "   or: %s\n", *usagestr++);
+	while (*usagestr) {
+		fprintf(stderr, "%s%s\n",
+				**usagestr ? "    " : "",
+				*usagestr);
+		usagestr++;
+	}
+
+	fputc('\n', stderr);
+	fprintf(stderr, "available subcommands:\n");
+	for (i = 0; i < subcmds->nr; i++) {
+		size_t pos;
+		int pad;
+
+		pos = fprintf(stderr, "    ");
+		pos += fprintf(stderr, "%s", subcmds->items[i].string);
+
+		if (pos <= USAGE_OPTS_WIDTH)
+			pad = USAGE_OPTS_WIDTH - pos;
+		else {
+			fputc('\n', stderr);
+			pad = USAGE_OPTS_WIDTH;
+		}
+		fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "",
+			((struct subcommand *)(subcmds->items[i].util))->help);
+	}
+	fputc('\n', stderr);
+}
+
 int cmd_notes(int argc, const char **argv, const char *prefix)
 {
-	int result;
+	int i;
 	const char *override_notes_ref = NULL;
+	struct string_list subcmds = STRING_LIST_INIT_NODUP;
+	struct string_list_item *item;
 	struct option options[] = {
 		OPT_STRING(0, "ref", &override_notes_ref, "notes_ref",
 			   "use notes from <notes_ref>"),
 		OPT_END()
 	};
+	struct subcommand util[] = {
+		{ "list", "list notes for given object", list },
+		{ "add", "add notes for given object", add },
+		{ "copy", "copy notes for first object onto second object", copy },
+		{ "append", "append notes to existing object", append_edit },
+		{ "edit", "edit notes for given object", append_edit },
+		{ "show", "show notes for given object", show },
+		{ "merge", "merge given notes ref into current notes ref", merge },
+		{ "remove", "remove notes for given objects", remove_cmd },
+		{ "prune",
+		  "remove all notes for non-existing/unreachable objects", prune },
+		{ "get-ref", "print the current notes ref", get_ref }
+	};
 
 	git_config(git_default_config, NULL);
 	argc = parse_options(argc, argv, prefix, options, git_notes_usage,

@@ -1081,28 +1131,18 @@ int cmd_notes(int argc, const char **argv, const char *prefix)
 		strbuf_release(&sb);
 	}
 
-	if (argc < 1 || !strcmp(argv[0], "list"))
-		result = list(argc, argv, prefix);
-	else if (!strcmp(argv[0], "add"))
-		result = add(argc, argv, prefix);
-	else if (!strcmp(argv[0], "copy"))
-		result = copy(argc, argv, prefix);
-	else if (!strcmp(argv[0], "append") || !strcmp(argv[0], "edit"))
-		result = append_edit(argc, argv, prefix);
-	else if (!strcmp(argv[0], "show"))
-		result = show(argc, argv, prefix);
-	else if (!strcmp(argv[0], "merge"))
-		result = merge(argc, argv, prefix);
-	else if (!strcmp(argv[0], "remove"))
-		result = remove_cmd(argc, argv, prefix);
-	else if (!strcmp(argv[0], "prune"))
-		result = prune(argc, argv, prefix);
-	else if (!strcmp(argv[0], "get-ref"))
-		result = get_ref(argc, argv, prefix);
-	else {
-		result = error(_("Unknown subcommand: %s"), argv[0]);
-		usage_with_options(git_notes_usage, options);
-	}
+	for (i = 0; i < ARRAY_SIZE(util); i++)
+		string_list_insert(&subcmds, util[i].name)->util = &util[i];
+	sort_string_list(&subcmds);
+
+	if (argc < 1)
+		return list(argc, argv, prefix) ? 1 : 0;
+
+	item = string_list_lookup(&subcmds, argv[0]);
+	if (item)
+		return ((struct subcommand *)(item->util))->callback(argc, argv, prefix) ? 1 : 0;
 
-	return result ? 1 : 0;
+	error("unknown subcommand: %s", argv[0]);
+	subcommand_usage(git_notes_usage, &subcmds);
+	exit(129);
 }