1 files changed, 10 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/core_ext/object/duplicable.rb b/activesupport/lib/active_support/core_ext/object/duplicable.rb
index c5d59128e5..665cb0f96d 100644
--- a/activesupport/lib/active_support/core_ext/object/duplicable.rb
+++ b/activesupport/lib/active_support/core_ext/object/duplicable.rb
@@ -91,3 +91,13 @@ class BigDecimal
     # can't dup, so use superclass implementation
   end
 end
+
+class Method
+  # Methods are not duplicable:
+  #
+  #  method(:puts).duplicable? # => false
+  #  method(:puts).dup         # => TypeError: allocator undefined for Method
+  def duplicable?
+    false
+  end
+end