busctl: convert to VERB_COMMAND and add --introspect-cli

The custom help() is replaced by a COMMAND() description, and
--introspect-cli is added. Verb and option column widths are kept
separate via COMMAND_HELP_SEPARATE, since the verb table is very wide,
as before.

src/busctl/busctl.c

@@ -26,12 +26,10 @@
 #include "fileio.h"
 #include "format-table.h"
 #include "glyph-util.h"
-#include "help-util.h"
 #include "log.h"
 #include "logarithm.h"
 #include "main-func.h"
 #include "memstream-util.h"
-#include "options.h"
 #include "os-util.h"
 #include "pager.h"
 #include "parse-argument.h"
@@ -77,6 +75,14 @@ static uint64_t arg_limit_signals = 1;
 
 STATIC_DESTRUCTOR_REGISTER(arg_matches, strv_freep);
 
+COMMAND(
+        "busctl\0",
+        "Introspect the D-Bus IPC bus.",
+        .man_pages = "busctl.1\0",
+        .pager_flags = &arg_pager_flags,
+        .flags = COMMAND_HELP_SEPARATE,  /* the verb table is very wide */
+);
+
 #define NAME_IS_ACQUIRED INT_TO_PTR(1)
 #define NAME_IS_ACTIVATABLE INT_TO_PTR(2)
 
@@ -2073,41 +2079,7 @@ static int verb_set_property(int argc, char *argv[], uintptr_t _data, void *user
         return 0;
 }
 
-static int help(void) {
-        _cleanup_(table_unrefp) Table *options = NULL, *verbs = NULL;
-        int r;
-
-        pager_open(arg_pager_flags);
-
-        r = verbs_get_help_table(&verbs);
-        if (r < 0)
-                return r;
-
-        r = option_parser_get_help_table(&options);
-        if (r < 0)
-                return r;
-
-        /* Note: column widths are not synced, because the verbs table is very wide. */
-
-        help_cmdline("[OPTIONS…] COMMAND …");
-        help_abstract("Introspect the D-Bus IPC bus.");
-
-        help_section("Commands");
-        r = table_print_or_warn(verbs);
-        if (r < 0)
-                return r;
-
-        help_section("Options");
-        r = table_print_or_warn(options);
-        if (r < 0)
-                return r;
-
-        help_man_page_reference("busctl", "1");
-
-        return 0;
-}
-
-VERB_COMMON_HELP(help);
+VERB_COMMON_HELP_AUTO("busctl");
 
 static int parse_argv(int argc, char *argv[], char ***remaining_args) {
         assert(argc >= 0);
@@ -2121,7 +2093,7 @@ static int parse_argv(int argc, char *argv[], char ***remaining_args) {
                 switch (c) {
 
                 OPTION_COMMON_HELP:
-                        return help();
+                        return command_print_help("busctl");
 
                 OPTION_COMMON_VERSION:
                         return version();
@@ -2305,6 +2277,9 @@ static int parse_argv(int argc, char *argv[], char ***remaining_args) {
 
                         arg_limit_signals = arg_limit_messages;
                         break;
+
+                OPTION_COMMON_INTROSPECT_CLI:
+                        return introspect_cli(arg_json_format_flags);
                 }
 
         if (arg_full < 0)

test/units/TEST-74-AUX-UTILS.introspect-cli.sh

@@ -11,6 +11,7 @@ export SYSTEMD_PAGER=cat
 
 # A smoke test for the introspection code
 INTROSPECTABLE=(
+    busctl
     homectl
     resolvectl
     systemd-ac-power