commit: abort commit if interactive add failed

Previously we ignored the result of calling add_interactive,
which meant that if an error occurred we simply committed
whatever happened to be in the index.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-commit.c

@@ -224,7 +224,8 @@ static char *prepare_index(int argc, const char **argv, const char *prefix)
 	const char **pathspec = NULL;
 
 	if (interactive) {
-		interactive_add(argc, argv, prefix);
+		if (interactive_add(argc, argv, prefix) != 0)
+			die("interactive add failed");
 		if (read_cache() < 0)
 			die("index file corrupt");
 		commit_style = COMMIT_AS_IS;