diff --git a/test/reline/helper.rb b/test/reline/helper.rb
index be155124a4..e3ce318c44 100644
--- a/test/reline/helper.rb
+++ b/test/reline/helper.rb
@@ -21,6 +21,8 @@ def test_mode(ansi: false)
     end
 
     def test_reset
+      remove_const('IOGate') if const_defined?('IOGate')
+      const_set('IOGate', Reline::GeneralIO)
       Reline.instance_variable_set(:@core, nil)
     end
   end