format-patch: allow a non-integral version numbers

The `-v<n>` option of `format-patch` can give nothing but an
integral iteration number to patches in a series.  Some people,
however, prefer to mark a new iteration with only a small fixup
with a non integral iteration number (e.g. an "oops, that was
wrong" fix-up patch for v4 iteration may be labeled as "v4.1").

Allow `format-patch` to take such a non-integral iteration
number.

`<n>` can be any string, such as '3.1' or '4rev2'. 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>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/log-tree.c b/log-tree.c
index 4531ceb..f3178a6 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -369,8 +369,14 @@ void fmt_output_subject(struct strbuf *filename,
 	int start_len = filename->len;
 	int max_len = start_len + info->patch_name_max - (strlen(suffix) + 1);
 
-	if (0 < info->reroll_count)
-		strbuf_addf(filename, "v%d-", info->reroll_count);
+	if (info->reroll_count) {
+		struct strbuf temp = STRBUF_INIT;
+
+		strbuf_addf(&temp, "v%s", info->reroll_count);
+		format_sanitized_subject(filename, temp.buf, temp.len);
+		strbuf_addstr(filename, "-");
+		strbuf_release(&temp);
+	}
 	strbuf_addf(filename, "%04d-%s", nr, subject);
 
 	if (max_len < filename->len)