Required fields on token_authenticatable

lib/devise/models/token_authenticatable.rb

@@ -27,6 +27,14 @@ module Devise
     module TokenAuthenticatable
       extend ActiveSupport::Concern
 
+      module ModuleMethods
+        extend self
+
+        def required_fields
+          [:authentication_token]
+        end
+      end
+
       # Generate new authentication token (a.k.a. "single access token").
       def reset_authentication_token
         self.authentication_token = self.class.authentication_token

test/models/token_authenticatable_test.rb

@@ -46,4 +46,10 @@ class TokenAuthenticatableTest < ActiveSupport::TestCase
     user = User.find_for_token_authentication(:auth_token => {'$ne' => user1.authentication_token})
     assert_nil user
   end
+
+  test 'required_fields should contain the fields that Devise uses' do
+    assert_equal Devise::Models::TokenAuthenticatable::ModuleMethods.required_fields.sort, [
+      :authentication_token
+    ]
+  end
 end