config: be strict on core.commentChar

We don't support comment _strings_ (at least not yet). And multi-byte
character encoding could also be misinterpreted.

The test with two commas is updated because it violates this. It's
added with the patch that introduces core.commentChar in eff80a9
(Allow custom "comment char" - 2013-01-16). It's not clear to me _why_
that behavior is wanted.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/config.c b/config.c
index a30cb5c..491a905 100644
--- a/config.c
+++ b/config.c
@@ -826,9 +826,13 @@ static int git_default_core_config(const char *var, const char *value)
 	if (!strcmp(var, "core.commentchar")) {
 		const char *comment;
 		int ret = git_config_string(&comment, var, value);
-		if (!ret)
+		if (ret)
+			return ret;
+		else if (comment[0] && !comment[1]) {
 			comment_line_char = comment[0];
-		return ret;
+		} else
+			return error("core.commentChar should only be one character");
+		return 0;
 	}
 
 	if (!strcmp(var, "core.askpass"))