From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Sat, 11 Sep 2021 02:34:45 GMT
Subject: Re: [PATCH v2 1/5] help: correct the usage string in -h and documentation
Message-ID: <87zgsjal88.fsf@evledraar.gmail.com>
In-Reply-To: <xmqqr1dvoqyo.fsf@gitster.g>


On Fri, Sep 10 2021, Junio C Hamano wrote:

> Ævar Arnfjörð Bjarmason  <avarab@gmail.com> writes:
>
>> diff --git a/Documentation/git-help.txt b/Documentation/git-help.txt
>> index 44fe8860b3f..568a0b606f3 100644
>> --- a/Documentation/git-help.txt
>> +++ b/Documentation/git-help.txt
>> @@ -9,7 +9,7 @@ SYNOPSIS
>>  --------
>>  [verse]
>>  'git help' [-a|--all [--[no-]verbose]] [-g|--guides]
>> -	   [-i|--info|-m|--man|-w|--web] [COMMAND|GUIDE]
>> +	   [[-i|--info] [-m|--man] [-w|--web]] [COMMAND|GUIDE]
>
> This one is good, but ...
>
>> diff --git a/builtin/help.c b/builtin/help.c
>> index b7eec06c3de..44ea2798cda 100644
>> --- a/builtin/help.c
>> +++ b/builtin/help.c
>> @@ -59,7 +59,8 @@ static struct option builtin_help_options[] = {
>>  };
>>  
>>  static const char * const builtin_help_usage[] = {
>> -	N_("git help [--all] [--guides] [--man | --web | --info] [<command>]"),
>> +	N_("git help [-a|--all] [-g|--guides] [--[no-]verbose]]\n"
>> +	   "         [[-i|--info] [-m|--man] [-w|--web]] [<command>]"),
>
> Aside from the addition of so-far-missing "verbose", which is
> obviously a good change, I am not sure if the other change is a good
> idea.
>
> This is because *_usage[] is designed to be always shown together
> with the list of options built from the option table the
> parse_options() uses, and the readers will see the correspondence
> between long and short options even more clear there.
>
>     $ git help -h
>     usage: git help [--all] [--guides] [--man | --web | --info] [<command>]
>
>         -a, --all             print all available commands
>         -g, --guides          print list of useful guides
>         -c, --config          print all configuration variable names
>         -m, --man             show man page
>         -w, --web             show manual in web browser
>         -i, --info            show info page
>         -v, --verbose         print command description
>
> If you look at output from 
>
>     $ git grep -A4 -e '_usage\[' builtin/\*.c
>
> you'll notice that many of them do not even spell out each option
> and instead have a single [<options>] placeholder unless the command
> has only very small number of options.  With the number of options
> that "git help" takes, it might even be warranted to switch to the
> more generic "git help [<option>...] [<command>]".
>
> Not a strict veto, but just making sure if the over-cluttering of
> the early lines in "help -h" output has been considered as a
> possible downside before suggesting this change.

That's a valid point, but if you look at:

    for cmd in $(git --list-cmds=builtins); do echo git-$cmd: && git -P $cmd -h | sed 's/^/    /'; done 2>&1|less

I think it's fair to say it's a fairly mixed bag, some have the brevity
you describe, others are attempting to list every possible option combo
etc.

This is one of the commands that's more like than the likes of
git-branch, git-worktree, git-stash, git-index-pack etc. than git-add,
git-apply, git-mv in the sense that it's trying to exhaustively mirror
the options between the documentation and the usage string.

I do think we should pick one, but I think migrating from one style to
the other just for this one command would be an unnecessary distraction
from a change that's not about changing that style in general, let's
just stick with the pattern we find here.

I do want to make them pretty and consistent eventually, this series is
just one small step on the way there.