1 files changed, 11 insertions, 1 deletions
diff --git a/activesupport/lib/active_support/core_ext/array/random_access.rb b/activesupport/lib/active_support/core_ext/array/random_access.rb
index 343003f6f7..5338836b29 100644
--- a/activesupport/lib/active_support/core_ext/array/random_access.rb
+++ b/activesupport/lib/active_support/core_ext/array/random_access.rb
@@ -1,6 +1,16 @@
 class Array
+  # This method is deprecated because it masks Kernel#rand within the Array class itself, 
+  # which may be used by a 3rd party library extending Array in turn. See
+  #
+  #   https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/4555
+  #
+  def rand # :nodoc:
+    ActiveSupport::Deprecation.warn "Array#rand is deprecated, use random_element instead", caller
+    random_element
+  end
+
   # Returns a random element from the array.
-  def rand
+  def random_element
     self[Kernel.rand(length)]
   end
 end