[PATCH] rebase -i: fix numbering in squash message

[Phillip Wood <phillip.wood@talktalk.net>]

From: Phillip Wood <phillip.wood@dunelm.org.uk>

Commit e12a7ef597 ("rebase -i: Handle "combination of <n> commits" with
GETTEXT_POISON", 2018-04-27) changed the way that individual commit
messages are labelled when squashing commits together. In doing so a
regression was introduced where the numbering of the messages is off by
one. This commit fixes that and adds a test for the numbering.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
---
 sequencer.c                | 4 ++--
 t/t3418-rebase-continue.sh | 4 +++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/sequencer.c b/sequencer.c
index 2eb5ec7227..77d3c2346f 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -1387,13 +1387,13 @@ static int update_squash_messages(enum todo_command command,
 		unlink(rebase_path_fixup_msg());
 		strbuf_addf(&buf, "\n%c ", comment_line_char);
 		strbuf_addf(&buf, _("This is the commit message #%d:"),
-			    ++opts->current_fixup_count);
+			    ++opts->current_fixup_count + 1);
 		strbuf_addstr(&buf, "\n\n");
 		strbuf_addstr(&buf, body);
 	} else if (command == TODO_FIXUP) {
 		strbuf_addf(&buf, "\n%c ", comment_line_char);
 		strbuf_addf(&buf, _("The commit message #%d will be skipped:"),
-			    ++opts->current_fixup_count);
+			    ++opts->current_fixup_count + 1);
 		strbuf_addstr(&buf, "\n\n");
 		strbuf_add_commented_lines(&buf, body, strlen(body));
 	} else
diff --git a/t/t3418-rebase-continue.sh b/t/t3418-rebase-continue.sh
index e9fd029160..ee871dd1bb 100755
--- a/t/t3418-rebase-continue.sh
+++ b/t/t3418-rebase-continue.sh
@@ -128,13 +128,15 @@ test_expect_success '--skip after failed fixup cleans commit message' '
 	: The first squash was skipped, therefore: &&
 	git show HEAD >out &&
 	test_i18ngrep "# This is a combination of 2 commits" out &&
+	test_i18ngrep "# This is the commit message #2:" out &&
 
 	(test_set_editor "$PWD/copy-editor.sh" && git rebase --skip) &&
 	git show HEAD >out &&
 	test_i18ngrep ! "# This is a combination" out &&
 
 	: Final squash failed, but there was still a squash &&
-	test_i18ngrep "# This is a combination of 2 commits" .git/copy.txt
+	test_i18ngrep "# This is a combination of 2 commits" .git/copy.txt &&
+	test_i18ngrep "# This is the commit message #2:" .git/copy.txt
 '
 
 test_expect_success 'setup rerere database' '
-- 
2.18.0