describe: when failing, tell the user about options that work

diff --git a/revision.c b/revision.c
index 35eca4a36185b1c5c40245748d0004fdaf0f6c00..9fc4e8d3818f29261b1963f4995bc36f8af31179 100644 (file)
--- a/revision.c
+++ b/revision.c
@@ -1159,8 +1159,10 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
                revs->simplify_history = 0;
        } else if (!strcmp(arg, "--relative-date")) {
                revs->date_mode = DATE_RELATIVE;
+               revs->date_mode_explicit = 1;
        } else if (!strncmp(arg, "--date=", 7)) {
                revs->date_mode = parse_date_format(arg + 7);
+               revs->date_mode_explicit = 1;
        } else if (!strcmp(arg, "--log-size")) {
                revs->show_log_size = 1;
        }