move expression tests to standard dir for guard

test/register/test_collector.rb

@@ -5,7 +5,7 @@ module Register
     def test_simple_collect
       Machine.new.boot
       objects = Register::Collector.collect_space
-      assert ((352 == objects.length) or (419 == objects.length)) , objects.length.to_s
+      assert ((352 == objects.length) or (420 == objects.length)) , objects.length.to_s
     end
   end
 end