Use rubocop --lint when no .rubocop.yml

* lisp/progmodes/ruby-mode.el (ruby-flymake-rubocop): When no
config file found, only run lint cops (bug#31760).

1 files changed, 2 insertions, 1 deletions

diff --git a/lisp/progmodes/ruby-mode.el b/lisp/progmodes/ruby-mode.el
index d60899cf182..2a50374765c 100644
--- a/lisp/progmodes/ruby-mode.el
+++ b/lisp/progmodes/ruby-mode.el
@@ -2324,7 +2324,8 @@ Only takes effect if RuboCop is installed."
     (when buffer-file-name
       (setq config-dir (locate-dominating-file buffer-file-name
                                                ruby-rubocop-config))
-      (when config-dir
+      (if (not config-dir)
+          (setq command (append command '("--lint")))
         (setq command (append command (list "--config"
                                             (expand-file-name ruby-rubocop-config
                                                               config-dir)))))