[PATCH v4] format-patch: allow a non-integral version numbers

From: ZheNing Hu <adlternative@gmail.com>

Usually we can only use `format-patch -v<n>` to generate integral version numbers patches, but sometimes a same fixup should be labeled as a non-integral version like `v1.1`, so teach `format-patch` to allow a non-integral version which may be helpful to send those patches.

`<n>` can be any string, such as `-v1.1`. In the case where it is a non-integral value, the "Range-diff" and "Interdiff" headers will not include the previous version.

Signed-off-by: ZheNing Hu <adlternative@gmail.com>
---
    [GSOC] format-patch: allow a non-integral version numbers
    
    There is a small question: in the case of --reroll-count=<n>, "n" is an
    integer, we output "n-1" in the patch instead of "m" specified by
    --previous-count=<m>,Should we switch the priority of these two: let "m"
    output?
    
    this want to fix #882 Thanks.

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-885%2Fadlternative%2Fformat_patch_non_intergral-v4
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-885/adlternative/format_patch_non_intergral-v4
Pull-Request: https://github.com/gitgitgadget/git/pull/885

Range-diff vs v3:

 1:  d4f38b78c464 ! 1:  cb1c0267e16b format-patch: allow a non-integral version numbers
     @@ Commit message
      
          Usually we can only use `format-patch -v<n>` to generate integral
          version numbers patches, but sometimes a same fixup should be
     -    labeled as a non-integral versions like `v1.1`, so teach `format-patch`
     -    to allow a non-integral versions may be helpful to send those patches.
     +    labeled as a non-integral version like `v1.1`, so teach `format-patch`
     +    to allow a non-integral version which may be helpful to send those
     +    patches.
      
     -    Since the original `format-patch` logic, if we specify a version `-v<n>`
     -    and commbine with `--interdiff` or `--rangediff`, the patch will output
     -    "Interdiff again v<n-1>:" or "Range-diff again v<n-1>:`, but this does
     -    not meet the requirements of our fractional version numbers, so if the
     -    user use a integral version number `-v<n>`, ensure that the output in
     -    the patch is still `v<n-1>`; otherwise, only output "Interdiff" or
     -    "Range-diff".
     +    `<n>` can be any string, such as `-v1.1`.  In the case where it
     +    is a non-integral value, the "Range-diff" and "Interdiff"
     +    headers will not include the previous version.
      
          Signed-off-by: ZheNing Hu <adlternative@gmail.com>
      
     @@ Documentation/git-format-patch.txt: populated with placeholder text.
       	Add a `To:` header to the email headers. This is in addition
      
       ## builtin/log.c ##
     -@@ builtin/log.c: static void print_bases(struct base_tree_info *bases, FILE *file)
     - 	oidclr(&bases->base_commit);
     - }
     - 
     --static const char *diff_title(struct strbuf *sb, int reroll_count,
     --		       const char *generic, const char *rerolled)
     -+static const char *diff_title(struct strbuf *sb,
     -+			const char *reroll_count_string,
     -+			const char*previous_count_string,
     -+			const char *generic, const char *rerolled)
     - {
     --	if (reroll_count <= 0)
     -+	if (!reroll_count_string || !previous_count_string)
     - 		strbuf_addstr(sb, generic);
     --	else /* RFC may be v0, so allow -v1 to diff against v0 */
     --		strbuf_addf(sb, rerolled, reroll_count - 1);
     -+	else if (previous_count_string)
     -+		strbuf_addf(sb, rerolled, previous_count_string);
     - 	return sb->buf;
     - }
     - 
      @@ builtin/log.c: int cmd_format_patch(int argc, const char **argv, const char *prefix)
       	int use_patch_format = 0;
       	int quiet = 0;
       	int reroll_count = -1;
      +	const char *reroll_count_string = NULL;
     -+	const char *previous_count_string = NULL;
       	char *cover_from_description_arg = NULL;
       	char *branch_name = NULL;
       	char *base_commit = NULL;
     @@ builtin/log.c: int cmd_format_patch(int argc, const char **argv, const char *pre
       		OPT_INTEGER(0, "start-number", &start_number,
       			    N_("start numbering patches at <n> instead of 1")),
      -		OPT_INTEGER('v', "reroll-count", &reroll_count,
     --			    N_("mark the series as Nth re-roll")),
      +		OPT_STRING('v', "reroll-count", &reroll_count_string, N_("reroll-count"),
     -+			    N_("mark the series as specified version re-roll")),
     + 			    N_("mark the series as Nth re-roll")),
       		OPT_INTEGER(0, "filename-max-length", &fmt_patch_name_max,
       			    N_("max length of output filename")),
     - 		OPT_CALLBACK_F(0, "rfc", &rev, NULL,
      @@ builtin/log.c: int cmd_format_patch(int argc, const char **argv, const char *prefix)
       	if (cover_from_description_arg)
       		cover_from_description_mode = parse_cover_from_description(cover_from_description_arg);
     @@ builtin/log.c: int cmd_format_patch(int argc, const char **argv, const char *pre
      -		strbuf_addf(&sprefix, "%s v%d",
      -			    rev.subject_prefix, reroll_count);
      -		rev.reroll_count = reroll_count;
     -+		char *endp;
      +
     -+		reroll_count = strtoul(reroll_count_string, &endp, 10);
     -+		if (!*endp && 0 < reroll_count) {
     -+			previous_count_string = xstrfmt("%d", reroll_count - 1);
     -+		}
     ++		strtol_i(reroll_count_string, 10, &reroll_count);
      +		strbuf_addf(&sprefix, "%s v%s",
      +			    rev.subject_prefix, reroll_count_string);
      +		rev.reroll_count = reroll_count_string;
       		rev.subject_prefix = strbuf_detach(&sprefix, NULL);
       	}
       
     -@@ builtin/log.c: int cmd_format_patch(int argc, const char **argv, const char *prefix)
     - 			die(_("--interdiff requires --cover-letter or single patch"));
     - 		rev.idiff_oid1 = &idiff_prev.oid[idiff_prev.nr - 1];
     - 		rev.idiff_oid2 = get_commit_tree_oid(list[0]);
     --		rev.idiff_title = diff_title(&idiff_title, reroll_count,
     --					     _("Interdiff:"),
     --					     _("Interdiff against v%d:"));
     -+		rev.idiff_title = diff_title(&idiff_title, reroll_count_string,
     -+					previous_count_string,
     -+					_("Interdiff:"),
     -+					_("Interdiff against v%s:"));
     - 	}
     - 
     - 	if (creation_factor < 0)
     -@@ builtin/log.c: int cmd_format_patch(int argc, const char **argv, const char *prefix)
     - 		rev.rdiff1 = rdiff1.buf;
     - 		rev.rdiff2 = rdiff2.buf;
     - 		rev.creation_factor = creation_factor;
     --		rev.rdiff_title = diff_title(&rdiff_title, reroll_count,
     --					     _("Range-diff:"),
     --					     _("Range-diff against v%d:"));
     -+		rev.rdiff_title = diff_title(&rdiff_title, reroll_count_string,
     -+					previous_count_string,
     -+					_("Range-diff:"),
     -+					_("Range-diff against v%s:"));
     - 	}
     - 
     - 	if (!signature) {
      
       ## log-tree.c ##
      @@ log-tree.c: void fmt_output_subject(struct strbuf *filename,

 Documentation/git-format-patch.txt |  1 +
 builtin/log.c                      | 13 ++++++++-----
 log-tree.c                         |  4 ++--
 revision.h                         |  2 +-
 t/t3206-range-diff.sh              | 16 ++++++++++++++++
 t/t4014-format-patch.sh            | 26 ++++++++++++++++++++++++++
 6 files changed, 54 insertions(+), 8 deletions(-)