Re: [PATCH v3 5/5] [GSOC] ref-filter: add %(rest) atom

>
> From: ZheNing Hu <adlternative@gmail.com>
>
> %(rest) is a atom used for cat-file batch mode, which can split
> the input lines at the first whitespace boundary, all characters
> before that whitespace are considered to be the object name;
> characters after that first run of whitespace (i.e., the "rest"
> of the line) are output in place of the %(rest) atom.
>
> In order to let "cat-file --batch=%(rest)" use the ref-filter
> interface, add %(rest) atom for ref-filter.
>
> Introduce the reject_atom() to reject the atom %(rest) for
> "git for-each-ref", "git branch", "git tag" and "git verify-tag".
>
> Suggected-by: Jacob Keller <jacob.keller@gmail.com>
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Hariom Verma <hariom18599@gmail.com>
> Signed-off-by: ZheNing Hu <adlternative@gmail.com>
> ---

>  ref-filter.c             | 25 +++++++++++++++++++++++++
>  ref-filter.h             |  5 ++++-
>  t/t3203-branch-output.sh |  4 ++++
>  t/t6300-for-each-ref.sh  |  4 ++++
>  t/t7004-tag.sh           |  4 ++++
>  t/t7030-verify-tag.sh    |  4 ++++
>  6 files changed, 45 insertions(+), 1 deletion(-)
>
> diff --git a/ref-filter.c b/ref-filter.c
> index 7cef839aaf1..85e9e657fe7 100644
> --- a/ref-filter.c
> +++ b/ref-filter.c
> @@ -157,6 +157,7 @@ enum atom_type {
>         ATOM_IF,
>         ATOM_THEN,
>         ATOM_ELSE,
> +       ATOM_REST,
>  };
>
>  /*
> @@ -559,6 +560,15 @@ static int if_atom_parser(struct ref_format *format, struct used_atom *atom,
>         return 0;
>  }
>
> +static int rest_atom_parser(struct ref_format *format, struct used_atom *atom,
> +                           const char *arg, struct strbuf *err)
> +{
> +       if (arg)
> +               return strbuf_addf_ret(err, -1, _("%%(rest) does not take arguments"));
> +       format->use_rest = 1;
> +       return 0;
> +}
> +
>  static int head_atom_parser(struct ref_format *format, struct used_atom *atom,
>                             const char *arg, struct strbuf *unused_err)
>  {
> @@ -615,6 +625,7 @@ static struct {
>         [ATOM_IF] = { "if", SOURCE_NONE, FIELD_STR, if_atom_parser },
>         [ATOM_THEN] = { "then", SOURCE_NONE },
>         [ATOM_ELSE] = { "else", SOURCE_NONE },
> +       [ATOM_REST] = { "rest", SOURCE_NONE, FIELD_STR, rest_atom_parser },
>         /*
>          * Please update $__git_ref_fieldlist in git-completion.bash
>          * when you add new atoms
> @@ -993,6 +1004,11 @@ static const char *find_next(const char *cp)
>         return NULL;
>  }
>
> +static int reject_atom(enum atom_type atom_type)
> +{
> +       return atom_type == ATOM_REST;
> +}
> +
>  /*
>   * Make sure the format string is well formed, and parse out
>   * the used atoms.
> @@ -1013,6 +1029,8 @@ int verify_ref_format(struct ref_format *format)
>                 at = parse_ref_filter_atom(format, sp + 2, ep, &err);
>                 if (at < 0)
>                         die("%s", err.buf);
> +               if (reject_atom(used_atom[at].atom_type))
> +                       die(_("this command reject atom %%(%.*s)"), (int)(ep - sp - 2), sp + 2);
>
>                 if ((format->quote_style == QUOTE_PYTHON ||
>                      format->quote_style == QUOTE_SHELL ||
> @@ -1932,6 +1950,12 @@ static int populate_value(struct ref_array_item *ref, struct strbuf *err)
>                         v->handler = else_atom_handler;
>                         v->s = xstrdup("");
>                         continue;
> +               } else if (atom_type == ATOM_REST) {
> +                       if (ref->rest)
> +                               v->s = xstrdup(ref->rest);
> +                       else
> +                               v->s = xstrdup("");
> +                       continue;
>                 } else
>                         continue;
>
> @@ -2149,6 +2173,7 @@ static struct ref_array_item *new_ref_array_item(const char *refname,
>
>         FLEX_ALLOC_STR(ref, refname, refname);
>         oidcpy(&ref->objectname, oid);
> +       ref->rest = NULL;
>
>         return ref;
>  }
> diff --git a/ref-filter.h b/ref-filter.h
> index 74fb423fc89..c15dee8d6b9 100644
> --- a/ref-filter.h
> +++ b/ref-filter.h
> @@ -38,6 +38,7 @@ struct ref_sorting {
>
>  struct ref_array_item {
>         struct object_id objectname;
> +       const char *rest;
>         int flag;
>         unsigned int kind;
>         const char *symref;
> @@ -76,14 +77,16 @@ struct ref_format {
>          * verify_ref_format() afterwards to finalize.
>          */
>         const char *format;
> +       const char *rest;
>         int quote_style;
> +       int use_rest;
>         int use_color;
>
>         /* Internal state to ref-filter */
>         int need_color_reset_at_eol;
>  };
>
> -#define REF_FORMAT_INIT { NULL, 0, -1 }
> +#define REF_FORMAT_INIT { .use_color = -1 }
>
>  /*  Macros for checking --merged and --no-merged options */
>  #define _OPT_MERGED_NO_MERGED(option, filter, h) \
> diff --git a/t/t3203-branch-output.sh b/t/t3203-branch-output.sh
> index 5325b9f67a0..6e94c6db7b5 100755
> --- a/t/t3203-branch-output.sh
> +++ b/t/t3203-branch-output.sh
> @@ -340,6 +340,10 @@ test_expect_success 'git branch --format option' '
>         test_cmp expect actual
>  '
>
> +test_expect_success 'git branch with --format=%(rest) must fail' '
> +       test_must_fail git branch --format="%(rest)" >actual
> +'
> +
>  test_expect_success 'worktree colors correct' '
>         cat >expect <<-EOF &&
>         * <GREEN>(HEAD detached from fromtag)<RESET>
> diff --git a/t/t6300-for-each-ref.sh b/t/t6300-for-each-ref.sh
> index 3d15d0a5360..0d2e062f791 100755
> --- a/t/t6300-for-each-ref.sh
> +++ b/t/t6300-for-each-ref.sh
> @@ -1211,6 +1211,10 @@ test_expect_success 'basic atom: head contents:trailers' '
>         test_cmp expect actual.clean
>  '
>
> +test_expect_success 'basic atom: rest must fail' '
> +       test_must_fail git for-each-ref --format="%(rest)" refs/heads/main
> +'
> +
>  test_expect_success 'trailer parsing not fooled by --- line' '
>         git commit --allow-empty -F - <<-\EOF &&
>         this is the subject
> diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
> index 2f72c5c6883..082be85dffc 100755
> --- a/t/t7004-tag.sh
> +++ b/t/t7004-tag.sh
> @@ -1998,6 +1998,10 @@ test_expect_success '--format should list tags as per format given' '
>         test_cmp expect actual
>  '
>
> +test_expect_success 'git tag -l with --format="%(rest)" must fail' '
> +       test_must_fail git tag -l --format="%(rest)" "v1*"
> +'
> +
>  test_expect_success "set up color tests" '
>         echo "<RED>v1.0<RESET>" >expect.color &&
>         echo "v1.0" >expect.bare &&
> diff --git a/t/t7030-verify-tag.sh b/t/t7030-verify-tag.sh
> index 3cefde9602b..10faa645157 100755
> --- a/t/t7030-verify-tag.sh
> +++ b/t/t7030-verify-tag.sh
> @@ -194,6 +194,10 @@ test_expect_success GPG 'verifying tag with --format' '
>         test_cmp expect actual
>  '
>
> +test_expect_success GPG 'verifying tag with --format="%(rest)" must fail' '
> +       test_must_fail git verify-tag --format="%(rest)" "fourth-signed"
> +'
> +
>  test_expect_success GPG 'verifying a forged tag with --format should fail silently' '
>         test_must_fail git verify-tag --format="tagname : %(tag)" $(cat forged1.tag) >actual-forged &&
>         test_must_be_empty actual-forged
> --
> gitgitgadget