Re: [PATCH 1/3] diff: factor out add_diff_options()

From: ZheNing Hu <adlternative@gmail.com>
To: "René Scharfe" <l.s.r@web.de>
Cc: "Git List" <git@vger.kernel.org>,
	"Junio C Hamano" <gitster@pobox.com>,
	"Ævar Arnfjörð Bjarmason" <avarab@gmail.com>,
	"Jeff King" <peff@peff.net>
Subject: Re: [PATCH 1/3] diff: factor out add_diff_options()
Date: Thu, 1 Dec 2022 22:11:59 +0800	[thread overview]
Message-ID: <CAOLTT8SpF=i6Lwc28SWSDf2uOqoxLpMHiVS5GefwYcCHigL2NQ@mail.gmail.com> (raw)
In-Reply-To: <19be5afa-63e8-5f11-c5f4-6f391677e4c4@web.de>

Hi,

René Scharfe <l.s.r@web.de> 于2022年12月1日周四 02:13写道：
>
> Add a function for appending the parseopts member of struct diff_options
> to a struct option array.  Use it in two sites instead of accessing the
> parseopts member directly.  Decoupling callers from diff internals like
> that allows us to change the latter.
>
> Signed-off-by: René Scharfe <l.s.r@web.de>
> ---
>  builtin/range-diff.c | 2 +-
>  diff-no-index.c      | 3 +--
>  diff.c               | 6 ++++++
>  diff.h               | 1 +
>  4 files changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/builtin/range-diff.c b/builtin/range-diff.c
> index e2a74efb42..aecfae12d3 100644
> --- a/builtin/range-diff.c
> +++ b/builtin/range-diff.c
> @@ -47,7 +47,7 @@ int cmd_range_diff(int argc, const char **argv, const char *prefix)
>
>         repo_diff_setup(the_repository, &diffopt);
>
> -       options = parse_options_concat(range_diff_options, diffopt.parseopts);
> +       options = add_diff_options(range_diff_options, &diffopt);
>         argc = parse_options(argc, argv, prefix, options,
>                              builtin_range_diff_usage, PARSE_OPT_KEEP_DASHDASH);
>
> diff --git a/diff-no-index.c b/diff-no-index.c
> index 18edbdf4b5..05fafd0019 100644
> --- a/diff-no-index.c
> +++ b/diff-no-index.c
> @@ -255,8 +255,7 @@ int diff_no_index(struct rev_info *revs,
>         };
>         struct option *options;
>
> -       options = parse_options_concat(no_index_options,
> -                                      revs->diffopt.parseopts);
> +       options = add_diff_options(no_index_options, &revs->diffopt);
>         argc = parse_options(argc, argv, revs->prefix, options,
>                              diff_no_index_usage, 0);
>         if (argc != 2) {
> diff --git a/diff.c b/diff.c
> index 1054a4b732..e01129f0ea 100644
> --- a/diff.c
> +++ b/diff.c
> @@ -5693,6 +5693,12 @@ static void prep_parse_options(struct diff_options *options)
>         memcpy(options->parseopts, parseopts, sizeof(parseopts));
>  }
>
> +struct option *add_diff_options(const struct option *parseopts,
> +                               struct diff_options *options)
> +{
> +       return parse_options_concat(parseopts, options->parseopts);
> +}
> +

This idea is very good. I am implementing `--scope` for git diff
recently [1], but I
don’t want this option to be directly inherited by commands such as git log,
git format-patch, etc. It would be best if the option can be added
dynamically...
This patch looks like it can be used to do just that! :)

>  int diff_opt_parse(struct diff_options *options,
>                    const char **av, int ac, const char *prefix)
>  {
> diff --git a/diff.h b/diff.h
> index fd33caeb25..c20a1ad76d 100644
> --- a/diff.h
> +++ b/diff.h
> @@ -539,6 +539,7 @@ int git_diff_ui_config(const char *var, const char *value, void *cb);
>  #define diff_setup(diffopts) repo_diff_setup(the_repository, diffopts)
>  #endif
>  void repo_diff_setup(struct repository *, struct diff_options *);
> +struct option *add_diff_options(const struct option *, struct diff_options *);
>  int diff_opt_parse(struct diff_options *, const char **, int, const char *);
>  void diff_setup_done(struct diff_options *);
>  int git_config_rename(const char *var, const char *value);
> --
> 2.38.1

Thanks!

[1]: https://lore.kernel.org/git/pull.1398.v3.git.1669723221.gitgitgadget@gmail.com/