Re: [PATCH v3 6/9] help: simplify by moving to OPT_CMDMODE()

Ævar Arnfjörð Bjarmason  [off-list ref] writes:

As preceding commits have incrementally established all of the --all,
--guides, --config and hidden --config-for-completion options are
mutually exclusive. So let's use OPT_CMDMODE() to parse the
command-line instead, and take advantage of its conflicting options
detection.

Sounds quite logical.

I think this makes the usage information that we emit slightly worse,
e.g. before we'd emit:

    $ git help --all --config
    fatal: --config and --all cannot be combined

    usage: git help [-a|--all] [--[no-]verbose]]
             [[-i|--info] [-m|--man] [-w|--web]] [<command>]
       or: git help [-g|--guides]
       or: git help [-c|--config]
    [...]
    $

And now:

    $ git help --all --config
    error: option `config' is incompatible with --all
    $

We often hear that our error messages for command line options are
unhelpful by being too broad, don't we?  I think the new one would
be much better by not scrolling away the most important part.  Those
who want to know about options other than --all and --config can
issue "git help -h" after seeing that single line error, but not
everybody has to do so.

But improving that is a general topic for parse-options.c improvement,
i.e. we should probably emit the full usage in that case.

Yes, absolutely.