Added required fields to lockable

lib/devise/models/lockable.rb

@@ -22,6 +22,10 @@ module Devise
 
       delegate :lock_strategy_enabled?, :unlock_strategy_enabled?, :to => "self.class"
 
+      def self.required_fields(klass)
+        [:failed_attempts, :unlock_at, :unlock_token]
+      end
+
       # Lock a user setting its locked_at to actual time.
       def lock_access!
         self.locked_at = Time.now.utc

test/models/lockable_test.rb

@@ -235,4 +235,12 @@ class LockableTest < ActiveSupport::TestCase
       assert_nil user.locked_at
     end
   end
-end
+
+  test 'required_fields should contain the fields that Devise uses' do
+    assert_equal Devise::Models::Lockable.required_fields(User).sort, [
+      :failed_attempts,
+      :unlock_at,
+      :unlock_token
+    ]
+  end
+end