gistfile1.txt

u = User.find(4)
=> #<User id: 4, .... >

u.save!
ActiveRecord::RecordInvalid: Validation failed: Path has already been taken
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/protected_attributes-1.0.5/lib/active_record/mass_assignment_security/associations.rb:109:in `create_record'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/protected_attributes-1.0.5/lib/active_record/mass_assignment_security/associations.rb:94:in `create!'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/associations/builder/singular_association.rb:27:in `create_namespace!'
	from /home/git/gitlab/app/observers/user_observer.rb:14:in `after_save'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/rails-observers-0.1.2/lib/rails/observers/active_model/observing.rb:352:in `update'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/rails-observers-0.1.2/lib/rails/observers/activerecord/observer.rb:118:in `block (2 levels) in define_callbacks'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activesupport-4.0.3/lib/active_support/callbacks.rb:416:in `_run__1900265881998485983__save__callbacks'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activesupport-4.0.3/lib/active_support/callbacks.rb:80:in `run_callbacks'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/callbacks.rb:302:in `create_or_update'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/persistence.rb:128:in `save!'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/validations.rb:57:in `save!'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/attribute_methods/dirty.rb:41:in `save!'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/transactions.rb:275:in `block in save!'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/transactions.rb:326:in `block in with_transaction_returning_status'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/connection_adapters/abstract/database_statements.rb:200:in `transaction'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/transactions.rb:209:in `transaction'
... 13 levels...
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/state_machine-1.2.0/lib/state_machine/transition_collection.rb:62:in `perform'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/state_machine-1.2.0/lib/state_machine/integrations/active_record.rb:502:in `block in around_save'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/state_machine-1.2.0/lib/state_machine/integrations/active_record.rb:530:in `block in transaction'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/connection_adapters/abstract/database_statements.rb:202:in `block in transaction'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/connection_adapters/abstract/database_statements.rb:210:in `within_new_transaction'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/connection_adapters/abstract/database_statements.rb:202:in `transaction'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-4.0.3/lib/active_record/transactions.rb:209:in `transaction'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/state_machine-1.2.0/lib/state_machine/integrations/active_record.rb:529:in `transaction'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/state_machine-1.2.0/lib/state_machine/integrations/active_record.rb:501:in `around_save'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/state_machine-1.2.0/lib/state_machine/integrations/active_record.rb:487:in `save!'
	from (irb):14
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/railties-4.0.3/lib/rails/commands/console.rb:90:in `start'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/railties-4.0.3/lib/rails/commands/console.rb:9:in `start'
	from /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/railties-4.0.3/lib/rails/commands.rb:62:in `<top (required)>'
	from bin/rails:8:in `require'