Anonymous Devise Issue: "[17] is not a symbol" [duplicate]

Question

Devise is throwing an issue I don't understand.

Using better errors gem; here's where it gets caught:

block in constantize(gem) activesupport-3.2.12/lib/active_support/inflector/methods.rb

  225         names = camel_cased_word.split('::')
  226         names.shift if names.empty? || names.first.empty?
  227 
  228         constant = Object
  229         names.each do |name|
  230           constant = constant.const_defined?(name, false) ? 
                  constant.const_get(name) : constant.const_missing(name)
  231         end
  232         constant
  233       end
  234     end 

Further details:

Request info:
Request parameters {"controller"=>"devise/sessions", "action"=>"new"}
Rack session       {"session_id"=>"a2bcc708204fb5dce015439f6881f67d","_csrf_token"=>"TzIKUgPy8y4F6kFfkDG/xfgCm4vMqkgReLHbK+cjeFI=", "warden.user.user.key"=>[[17], "$2a$10$/WvxkLxIdgHOMxg8nus6cu"]}


Local Variables:
name      [17]
camel_cased_word [17]
names    [[17]]
constant Object

Any ideas? What further info would be useful?

Here's a chunk off the end of the trace:

block in ActiveSupport::Inflector.constantize
(gem) activesupport-3.2.12/lib/active_support/inflector/methods.rb, line 230
ActiveSupport::Inflector.constantize
(gem) activesupport-3.2.12/lib/active_support/inflector/methods.rb, line 229
Warden::SessionSerializer#deserialize
(gem) devise-2.2.3/lib/devise/rails/warden_compat.rb, line 27
Warden::SessionSerializer#fetch
(gem) warden-1.2.1/lib/warden/session_serializer.rb, line 35
Warden::Proxy#user
(gem) warden-1.2.1/lib/warden/proxy.rb, line 212
Warden::Proxy#_perform_authentication
(gem) warden-1.2.1/lib/warden/proxy.rb, line 318
Warden::Proxy#authenticate
(gem) warden-1.2.1/lib/warden/proxy.rb, line 104
Warden::Proxy#authenticate?
(gem) warden-1.2.1/lib/warden/proxy.rb, line 114
Devise::SessionsController#require_no_authentication
(gem) devise-2.2.3/app/controllers/devise_controller.rb, line 124
Devise::SessionsController#
_run__642094268016367352__process_action__582726832569976772__callbacks
(gem) activesupport-3.2.12/lib/active_support/callbacks.rb, line 418
Devise::SessionsController.__run_callback
(gem) activesupport-3.2.12/lib/active_support/callbacks.rb, line 405
Devise::SessionsController#_run_process_action_callbacks
(gem) activesupport-3.2.12/lib/active_support/callbacks.rb, line 385
Devise::SessionsController#run_callbacks
(gem) activesupport-3.2.12/lib/active_support/callbacks.rb, line 81
Devise::SessionsController#process_action
(gem) actionpack-3.2.12/lib/abstract_controller/callbacks.rb, line 17
Devise::SessionsController#process_action
(gem) actionpack-3.2.12/lib/action_controller/metal/rescue.rb, line 29
block in Devise::SessionsController#process_action
(gem) actionpack-3.2.12/lib/action_controller/metal/instrumentation.rb, line 30
block in ActiveSupport::Notifications.instrument
(gem) activesupport-3.2.12/lib/active_support/notifications.rb, line 123
ActiveSupport::Notifications::Instrumenter#instrument
(gem) activesupport-3.2.12/lib/active_support/notifications/instrumenter.rb, line 20
ActiveSupport::Notifications.instrument
(gem) activesupport-3.2.12/lib/active_support/notifications.rb, line 123
Devise::SessionsController#process_action
(gem) actionpack-3.2.12/lib/action_controller/metal/instrumentation.rb, line 29
Devise::SessionsController#process_action

Answer 1

I updated from 2.0.4 to 2.2.4 and that happened me when I changed to a stable branch of my project with the old version. The solution was to clear all the cookies in the browser for my localhost. In your case would be the server where you're running your application.