Subject: Re: [PATCH v2 2/5] help: correct usage & behavior of "git help --guides"

From: Junio C Hamano <[email-masked]>
Date: Fri, 10 Sep 2021 18:22:50 -0700

Ævar Arnfjörð Bjarmason  <[email-masked]> writes:

> As noted in 65f98358c0c (builtin/help.c: add --guide option,
> 2013-04-02) and a133737b809 (doc: include --guide option description
> for "git help", 2013-04-02) which introduced the --guide option it
> cannot be combined with e.g. <command>.

Missing comman ',' between 'option' and 'it'.

> Change both the usage string to reflect that, and test and assert for

I couldn't immediately tell which two things "both the usage string"
is referring to.  Presumably in the doc and "help -h" output?

> this behavior in the command itself. Now that we assert this in code
> we don't need to exhaustively describe the previous confusing behavior
> in the documentation either, instead of silently ignoring the provided
> argument we'll now error out.
>
> The comment being removed was added in 15f7d494380 (builtin/help.c:
> split "-a" processing into two, 2013-04-02). The "Ignore any remaining
> args" part of it is now no longer applicable as explained above, let's
> just remove it entirely, it's rather obvious that if we're returning
> we're done.

Three sentences strung together with two commas ',' in between at
the end of this paragraph.  "A, let's B, it's C" -> "A. Let's B,
because it's C" or something.

> diff --git a/Documentation/git-help.txt b/Documentation/git-help.txt
> index 568a0b606f3..cb8e3d4da9e 100644
> --- a/Documentation/git-help.txt
> +++ b/Documentation/git-help.txt
> @@ -8,8 +8,9 @@ git-help - Display help information about Git
>  SYNOPSIS
>  --------
>  [verse]
> -'git help' [-a|--all [--[no-]verbose]] [-g|--guides]
> +'git help' [-a|--all [--[no-]verbose]]
>  	   [[-i|--info] [-m|--man] [-w|--web]] [COMMAND|GUIDE]
> +'git help' [-g|--guides]

Good.

> diff --git a/builtin/help.c b/builtin/help.c
> index 44ea2798cda..51b18c291d8 100644
> --- a/builtin/help.c
> +++ b/builtin/help.c
> @@ -59,8 +59,9 @@ static struct option builtin_help_options[] = {
>  };
>  
>  static const char * const builtin_help_usage[] = {
> -	N_("git help [-a|--all] [-g|--guides] [--[no-]verbose]]\n"
> +	N_("git help [-a|--all] [--[no-]verbose]]\n"
>  	   "         [[-i|--info] [-m|--man] [-w|--web]] [<command>]"),
> +	N_("git help [-g|--guides]"),

Good.  I still think -s|--long is cluttering than helping, though.

> +	/* Options that take no further arguments */
> +	if (argc && show_guides)
> +		usage_msg_opt(_("--guides cannot be combined with other options"),
> +			      builtin_help_usage, builtin_help_options);

At this point we have called parse_options() and there is no further
funky command line parsing involved, so non-zero argc does mean we
have something --guides does not know what to do.  Good.

> @@ -582,9 +588,6 @@ int cmd_help(int argc, const char **argv, const char *prefix)
>  
>  	if (show_all || show_guides) {
>  		printf("%s\n", _(git_more_info_string));
> -		/*
> -		* We're done. Ignore any remaining args
> -		*/
>  		return 0;
>  	}
>  
> diff --git a/t/t0012-help.sh b/t/t0012-help.sh
> index 5679e29c624..c3aa016fd30 100755
> --- a/t/t0012-help.sh
> +++ b/t/t0012-help.sh
> @@ -34,6 +34,10 @@ test_expect_success 'basic help commands' '
>  	git help -a >/dev/null
>  '
>  
> +test_expect_success 'invalid usage' '
> +	test_expect_code 129 git help -g git-add

;-)  

I would have expected a bare "add" not "git-add" here, but it
is OK.  It is funny that "git help git-add" still works, but
that is a bug that is unrelated to this patch.

> +'
> +
>  test_expect_success "works for commands and guides by default" '
>  	configure_help &&
>  	git help status &&