added helper method for rbx

hsbt · hsbt · commit e7e11037118a · 2016-06-28T15:08:28.000+09:00
diff --git a/test/helper.rb b/test/helper.rb
@@ -115,5 +115,9 @@ def jruby9?
     jruby? && (JRUBY_VERSION >= '9.0.0.0')
   end
 
+  def rbx?
+    RUBY_ENGINE == 'rbx'
+  end
+
   include RakefileDefinitions
 end
