diff --git a/test/ruby/test_pattern_matching.rb b/test/ruby/test_pattern_matching.rb
index db6ad06b82..cfe3bd1e19 100644
--- a/test/ruby/test_pattern_matching.rb
+++ b/test/ruby/test_pattern_matching.rb
@@ -1331,7 +1331,7 @@ END
     end
 
     assert_block do
-      case {}
+      case C.new({})
       in {}
         C.keys == nil
       end