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>

2 files changed, 58 insertions, 0 deletions

diff --git a/t/t3206-range-diff.sh b/t/t3206-range-diff.sh
index 1b26c4c2ef..e30bc48a29 100755
--- a/t/t3206-range-diff.sh
+++ b/t/t3206-range-diff.sh
@@ -521,6 +521,30 @@ test_expect_success 'format-patch --range-diff as commentary' '
 	grep "> 1: .* new message" 0001-*
 '
 
+test_expect_success 'format-patch --range-diff reroll-count with a non-integer' '
+	git format-patch --range-diff=HEAD~1 -v2.9 HEAD~1 >actual &&
+	test_when_finished "rm v2.9-0001-*" &&
+	test_line_count = 1 actual &&
+	test_i18ngrep "^Range-diff:$" v2.9-0001-* &&
+	grep "> 1: .* new message" v2.9-0001-*
+'
+
+test_expect_success 'format-patch --range-diff reroll-count with a integer' '
+	git format-patch --range-diff=HEAD~1 -v2 HEAD~1 >actual &&
+	test_when_finished "rm v2-0001-*" &&
+	test_line_count = 1 actual &&
+	test_i18ngrep "^Range-diff ..* v1:$" v2-0001-* &&
+	grep "> 1: .* new message" v2-0001-*
+'
+
+test_expect_success 'format-patch --range-diff with v0' '
+	git format-patch --range-diff=HEAD~1 -v0 HEAD~1 >actual &&
+	test_when_finished "rm v0-0001-*" &&
+	test_line_count = 1 actual &&
+	test_i18ngrep "^Range-diff:$" v0-0001-* &&
+	grep "> 1: .* new message" v0-0001-*
+'
+
 test_expect_success 'range-diff overrides diff.noprefix internally' '
 	git -c diff.noprefix=true range-diff HEAD^...
 '
diff --git a/t/t4014-format-patch.sh b/t/t4014-format-patch.sh
index cdd3154e70..712d4b5ddf 100755
--- a/t/t4014-format-patch.sh
+++ b/t/t4014-format-patch.sh
@@ -386,6 +386,30 @@ test_expect_success 'reroll count (-v)' '
 	! grep -v "^Subject: \[PATCH v4 [0-3]/3\] " subjects
 '
 
+test_expect_success 'reroll count (-v) with a fractional number' '
+	rm -fr patches &&
+	git format-patch -o patches --cover-letter -v4.4 main..side >list &&
+	! grep -v "^patches/v4.4-000[0-3]-" list &&
+	sed -n -e "/^Subject: /p" $(cat list) >subjects &&
+	! grep -v "^Subject: \[PATCH v4.4 [0-3]/3\] " subjects
+'
+
+test_expect_success 'reroll (-v) count with a non number' '
+	rm -fr patches &&
+	git format-patch -o patches --cover-letter -v4rev2 main..side >list &&
+	! grep -v "^patches/v4rev2-000[0-3]-" list &&
+	sed -n -e "/^Subject: /p" $(cat list) >subjects &&
+	! grep -v "^Subject: \[PATCH v4rev2 [0-3]/3\] " subjects
+'
+
+test_expect_success 'reroll (-v) count with a non-pathname character' '
+	rm -fr patches &&
+	git format-patch -o patches --cover-letter -v4---..././../--1/.2//  main..side >list &&
+	! grep -v "patches/v4-\.-\.-\.-1-\.2-000[0-3]-" list &&
+	sed -n -e "/^Subject: /p" $(cat list) >subjects &&
+	! grep -v "^Subject: \[PATCH v4---\.\.\./\./\.\./--1/\.2// [0-3]/3\] " subjects
+'
+
 check_threading () {
 	expect="$1" &&
 	shift &&
@@ -2255,6 +2279,16 @@ test_expect_success 'interdiff: reroll-count' '
 	test_i18ngrep "^Interdiff ..* v1:$" v2-0000-cover-letter.patch
 '
 
+test_expect_success 'interdiff: reroll-count with a non-integer' '
+	git format-patch --cover-letter --interdiff=boop~2 -v2.2 -1 boop &&
+	test_i18ngrep "^Interdiff:$" v2.2-0000-cover-letter.patch
+'
+
+test_expect_success 'interdiff: reroll-count with a integer' '
+	git format-patch --cover-letter --interdiff=boop~2 -v2 -1 boop &&
+	test_i18ngrep "^Interdiff ..* v1:$" v2-0000-cover-letter.patch
+'
+
 test_expect_success 'interdiff: solo-patch' '
 	cat >expect <<-\EOF &&
 	  +fleep