1  module ActiveSupport #:nodoc:
   2    module CoreExtensions #:nodoc:
   3      module Array #:nodoc:
   4        module RandomAccess
   5          # This method is deprecated because it masks Kernel#rand within the Array class itself, 
   6          # which may be used by a 3rd party library extending Array in turn. See
   7          #
   8          #   https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/4555
   9          #
  10          def rand # :nodoc:
  11            ActiveSupport::Deprecation.warn 'Array#rand is deprecated and will be removed in Rails 3. Use Array#sample instead', caller
  12            sample
  13          end
  14 
  15          # Returns a random element from the array.
  16          def random_element # :nodoc:
  17            ActiveSupport::Deprecation.warn 'Array#random_element is deprecated and will be removed in Rails 3. Use Array#sample instead', caller
  18            sample
  19          end
  20 
  21          # Backport of Array#sample based on Marc-Andre Lafortune's http://github.com/marcandre/backports/
  22          def sample(n=nil)
  23            return self[Kernel.rand(size)] if n.nil?
  24            n = n.to_int
  25          rescue Exception => e
  26            raise TypeError, "Coercion error: #{n.inspect}.to_int => Integer failed:\n(#{e.message})"
  27          else
  28            raise TypeError, "Coercion error: #{n}.to_int did NOT return an Integer (was #{n.class})" unless n.kind_of? ::Integer
  29            raise ArgumentError, "negative array size" if n < 0
  30            n = size if n > size
  31            result = ::Array.new(self)
  32            n.times do |i|
  33              r = i + Kernel.rand(size - i)
  34              result[i], result[r] = result[r], result[i]
  35            end
  36            result[n..size] = []
  37            result
  38          end unless method_defined? :sample
  39        end
  40      end
  41    end
  42  end