git-mergetool.sh: avoid "test <cond> -a/-o <cond>"

diff --git a/config.c b/config.c
index c227aa85177724354b3c9740ec62ea2ce521ac62..3c3e31448e5be385f9302ccce9c6993667014e5b 100644 (file)
--- a/config.c
+++ b/config.c
@@ -826,9 +826,16 @@ 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 (!strcasecmp(comment, "auto"))
+                       auto_comment_line_char = 1;
+               else if (comment[0] && !comment[1]) {
                        comment_line_char = comment[0];
-               return ret;
+                       auto_comment_line_char = 0;
+               } else
+                       return error("core.commentChar should only be one character");
+               return 0;
        }
 
        if (!strcmp(var, "core.askpass"))