Rails has removed SecureRandom from ActiveSupport in Rails 3.2,

deprecated

* Changing references in generators and encryptable_test

lib/generators/devise/install_generator.rb

@@ -1,4 +1,4 @@
-require 'active_support/secure_random'
+require 'securerandom'
 
 module Devise
   module Generators
@@ -21,4 +21,4 @@ module Devise
       end
     end
   end
-end
+end

lib/generators/templates/devise.rb

@@ -54,7 +54,7 @@ Devise.setup do |config|
   config.stretches = 10
 
   # Setup a pepper to generate the encrypted password.
-  # config.pepper = <%= ActiveSupport::SecureRandom.hex(64).inspect %>
+  # config.pepper = <%= SecureRandom.hex(64).inspect %>
 
   # ==> Configuration for :confirmable
   # The time you want to give your user to confirm his account. During this time

test/models/encryptable_test.rb

@@ -31,7 +31,7 @@ class EncryptableTest < ActiveSupport::TestCase
 
   test 'should generate a base64 hash using SecureRandom for password salt' do
     swap_with_encryptor Admin, :sha1 do
-      ActiveSupport::SecureRandom.expects(:base64).with(15).returns('friendly_token')
+      SecureRandom.expects(:base64).with(15).returns('friendly_token')
       assert_equal 'friendly_token', create_admin.password_salt
     end
   end