notes.c: Use two newlines (instead of one) when concatenating notes

When using combine_notes_concatenate() to concatenate notes, it currently
ensures exactly one newline character between the given notes. However,
when using builtin/notes.c:create_note() to concatenate notes (e.g. by
'git notes append'), it adds a newline character to the trailing newline
of the preceding notes object, thus resulting in _two_ newlines (aka. a
blank line) separating contents of the two notes.

This patch brings combine_notes_concatenate() into consistency with
builtin/notes.c:create_note(), by ensuring exactly _two_ newline characters
between concatenated notes.

The patch also changes a few notes-related selftests accordingly.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/notes.c b/notes.c
index 1674391d38..09a93abca1 100644
--- a/notes.c
+++ b/notes.c
@@ -812,16 +812,17 @@ int combine_notes_concatenate(unsigned char *cur_sha1,
 		return 0;
 	}
 
-	/* we will separate the notes by a newline anyway */
+	/* we will separate the notes by two newlines anyway */
 	if (cur_msg[cur_len - 1] == '\n')
 		cur_len--;
 
 	/* concatenate cur_msg and new_msg into buf */
-	buf_len = cur_len + 1 + new_len;
+	buf_len = cur_len + 2 + new_len;
 	buf = (char *) xmalloc(buf_len);
 	memcpy(buf, cur_msg, cur_len);
 	buf[cur_len] = '\n';
-	memcpy(buf + cur_len + 1, new_msg, new_len);
+	buf[cur_len + 1] = '\n';
+	memcpy(buf + cur_len + 2, new_msg, new_len);
 	free(cur_msg);
 	free(new_msg);