help: error if [-a|-g|-c] and [-i|-m|-w] are combined

Add more sanity checking to "git help" usage by erroring out if these
man viewer options are combined with incompatible command-modes that
will never use these documentation viewers.

This continues the work started in d35d03cf93e (help: simplify by
moving to OPT_CMDMODE(), 2021-09-22) of adding more sanity checking to
"git help". Doing this allows us to clarify the "SYNOPSIS" in the
documentation, and the "git help -h" output.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/help.c b/builtin/help.c
index b682446bbf5e5f73c683dc828fafe154f65e0f1c..1fc45adfcc7e239bff52959f6d05869558ba05b5 100644 (file)
--- a/builtin/help.c
+++ b/builtin/help.c
@@ -574,12 +574,40 @@ static const char *check_git_cmd(const char* cmd)
        return cmd;
 }
 
-static void opt_mode_usage(int argc, const char *opt_mode)
+static void no_help_format(const char *opt_mode, enum help_format fmt)
+{
+       const char *opt_fmt;
+
+       switch (fmt) {
+       case HELP_FORMAT_NONE:
+               return;
+       case HELP_FORMAT_MAN:
+               opt_fmt = "--man";
+               break;
+       case HELP_FORMAT_INFO:
+               opt_fmt = "--info";
+               break;
+       case HELP_FORMAT_WEB:
+               opt_fmt = "--web";
+               break;
+       default:
+               BUG("unreachable");
+       }
+
+       usage_msg_optf(_("options '%s' and '%s' cannot be used together"),
+                      builtin_help_usage, builtin_help_options, opt_mode,
+                      opt_fmt);
+}
+
+static void opt_mode_usage(int argc, const char *opt_mode,
+                          enum help_format fmt)
 {
        if (argc)
                usage_msg_optf(_("the '%s' option doesn't take any non-option arguments"),
                               builtin_help_usage, builtin_help_options,
                               opt_mode);
+
+       no_help_format(opt_mode, fmt);
 }
 
 int cmd_help(int argc, const char **argv, const char *prefix)
@@ -594,7 +622,7 @@ int cmd_help(int argc, const char **argv, const char *prefix)
 
        switch (cmd_mode) {
        case HELP_ACTION_ALL:
-               opt_mode_usage(argc, "--all");
+               opt_mode_usage(argc, "--all", help_format);
                if (verbose) {
                        setup_pager();
                        list_all_cmds_help();
@@ -606,20 +634,21 @@ int cmd_help(int argc, const char **argv, const char *prefix)
                printf("%s\n", _(git_more_info_string));
                break;
        case HELP_ACTION_GUIDES:
-               opt_mode_usage(argc, "--guides");
+               opt_mode_usage(argc, "--guides", help_format);
                list_guides_help();
                printf("%s\n", _(git_more_info_string));
                return 0;
        case HELP_ACTION_CONFIG_FOR_COMPLETION:
-               opt_mode_usage(argc, "--config-for-completion");
+               opt_mode_usage(argc, "--config-for-completion", help_format);
                list_config_help(SHOW_CONFIG_VARS);
                return 0;
        case HELP_ACTION_CONFIG_SECTIONS_FOR_COMPLETION:
-               opt_mode_usage(argc, "--config-sections-for-completion");
+               opt_mode_usage(argc, "--config-sections-for-completion",
+                              help_format);
                list_config_help(SHOW_CONFIG_SECTIONS);
                return 0;
        case HELP_ACTION_CONFIG:
-               opt_mode_usage(argc, "--config");
+               opt_mode_usage(argc, "--config", help_format);
                setup_pager();
                list_config_help(SHOW_CONFIG_HUMAN);
                printf("\n%s\n", _("'git help config' for more information"));

diff --git a/t/t0012-help.sh b/t/t0012-help.sh
index c87730aa920ee5a5f977c579b184ecfb22b720a5..f12783fd15372633ca068c645054fa88446becd8 100755 (executable)
--- a/t/t0012-help.sh
+++ b/t/t0012-help.sh
@@ -49,6 +49,16 @@ test_expect_success 'invalid usage' '
        test_expect_code 129 git help --config-sections-for-completion add
 '
 
+for opt in '-a' '-g' '-c' '--config-for-completion' '--config-sections-for-completion'
+do
+       test_expect_success "invalid usage of '$opt' with [-i|-m|-w]" '
+               git help $opt &&
+               test_expect_code 129 git help $opt -i &&
+               test_expect_code 129 git help $opt -m &&
+               test_expect_code 129 git help $opt -w
+       '
+done
+
 test_expect_success "works for commands and guides by default" '
        configure_help &&
        git help status &&