Re: [PATCH v3 2/2] builtin/config.c: prefer `--type=bool` over `--bool`, etc.

[Eric Sunshine <sunshine@sunshineco.com>]

On Wed, Apr 4, 2018 at 2:07 AM, Taylor Blau <me@ttaylorr.com> wrote:
> `git config` has long allowed the ability for callers to provide a 'type
> specifier', which instructs `git config` to (1) ensure that incoming
> values are satisfiable under that type, and (2) that outgoing values are
> canonicalized under that type.
>
> In another series, we propose to add extend this functionality with
> `--color` and `--default` to replace `--get-color`.
>
> However, we traditionally use `--color` to mean "colorize this output",
> instead of "this value should be treated as a color".
>
> Currently, `git config` does not support this kind of colorization, but
> we should be careful to avoid inhabiting this option too soon, so that
> `git config` can support `--color` (in the traditional sense) in the
> future, if that is desired.
>
> In this patch, we prefer `--type=[int|bool|bool-or-int|...]` over
> `--int`, `--bool`, and etc. This allows the aforementioned other patch
> to add `--color` (in the non-traditional sense) via `--type=color`,
> instead of `--color`.

I always find this last sentence confusing since it's not clear to
which ilk of "--color" option you refer. Perhaps say instead something
like:

    This normalization will allow the aforementioned upcoming patch to
    support querying a color value with a default via "--type=color
    --default=...".

> Signed-off-by: Taylor Blau <me@ttaylorr.com>
> ---
> diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt
> @@ -160,30 +158,34 @@ See also <<FILES>>.
> +--type [type]::
> +  'git config' will ensure that any input output is valid under the given type
> +  constraint(s), and will canonicalize outgoing values in `[type]`'s canonical
> +  form.

Do the brackets in "[type]" mean that the argument is optional? If so,
what does 'type' default to when not specified? The documentation
should discuss this.

> diff --git a/builtin/config.c b/builtin/config.c
> @@ -61,6 +61,33 @@ static int show_origin;
> +static int option_parse_type(const struct option *opt, const char *arg,
> +                            int unset)
> +{
> +       [...]
> +       if (!strcmp(arg, "bool"))
> +               *type = TYPE_BOOL;
> +       else if (!strcmp(arg, "int"))
> +               *type = TYPE_INT;
> +       else if (!strcmp(arg, "bool-or-int"))
> +               *type = TYPE_BOOL_OR_INT;
> +       else if (!strcmp(arg, "path"))
> +               *type = TYPE_PATH;
> +       else if (!strcmp(arg, "expiry-date"))
> +               *type = TYPE_EXPIRY_DATE;
> +       else {
> +               die(_("unexpected --type argument, %s"), arg);

"unexpected" doesn't seem like the best word choice since an argument
to --type _is_ expected. Perhaps you mean "unrecognized"?

> +               return 1;
> +       }
> +       return 0;
> +}