From d51f9d2e2f8fd62633db584461595c142eeed170 Mon Sep 17 00:00:00 2001
From: Masahiro Nakagawa <repeatedly@gmail.com>
Date: Fri, 10 Feb 2017 15:35:36 +0900
Subject: [PATCH] Revert "Use BasicObject for cleanroom"

---
 lib/fluent/plugin/filter_record_transformer.rb | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/fluent/plugin/filter_record_transformer.rb b/lib/fluent/plugin/filter_record_transformer.rb
index ec2b749dc2..62d6142a79 100644
--- a/lib/fluent/plugin/filter_record_transformer.rb
+++ b/lib/fluent/plugin/filter_record_transformer.rb
@@ -308,10 +308,14 @@ def expand(str, placeholders, force_stringify = false)
         raise "failed to expand `#{str}` : error = #{e}"
       end
 
-      class CleanroomExpander < BasicObject
+      class CleanroomExpander
         def expand(__str_to_eval__, tag, time, record, tag_parts, tag_prefix, tag_suffix, hostname)
           instance_eval(__str_to_eval__)
         end
+
+        (Object.instance_methods).each do |m|
+          undef_method m unless m.to_s =~ /^__|respond_to_missing\?|object_id|public_methods|instance_eval|method_missing|define_singleton_method|respond_to\?|new_ostruct_member/
+        end
       end
     end
   end