2 files changed, 13 insertions, 1 deletions
diff --git a/activesupport/lib/active_support/core_ext/object/blank.rb b/activesupport/lib/active_support/core_ext/object/blank.rb
index 7271671908..d67711f3b8 100644
--- a/activesupport/lib/active_support/core_ext/object/blank.rb
+++ b/activesupport/lib/active_support/core_ext/object/blank.rb
@@ -1,5 +1,4 @@
 # encoding: utf-8
-require 'active_support/core_ext/string/encoding'
 
 class Object
   # An object is blank if it's false, empty, or a whitespace string.
diff --git a/activesupport/lib/active_support/core_ext/object/duplicable.rb b/activesupport/lib/active_support/core_ext/object/duplicable.rb
index 9d044eba71..9d1630bb7c 100644
--- a/activesupport/lib/active_support/core_ext/object/duplicable.rb
+++ b/activesupport/lib/active_support/core_ext/object/duplicable.rb
@@ -104,3 +104,16 @@ class Module
     false
   end
 end
+
+require 'bigdecimal'
+class BigDecimal
+  begin
+    BigDecimal.new('4.56').dup
+
+    def duplicable?
+      true
+    end
+  rescue TypeError
+    # can't dup, so use superclass implementation
+  end
+end