Question

Having some huge headaches with migrations not seeming to run. No idea why – giving me the irrits! I don’t know what the heck ‘visitor’ is.

$ bundle exec rake db:migrate --trace

** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
** Invoke db:load_config (first_time)
** Invoke rails_env (first_time)
** Execute rails_env
** Execute db:load_config
** Execute db:migrate
rake aborted!
undefined method `visitor' for #    <ActiveRecord::ConnectionAdapters::SQLite3Adapter:0x007fcdcbdd8308>
/Users/danbronsema/.rvm/gems/ruby-1.9.2-p290@edge/gems/arel-2.1.5/lib/arel/tree_manager.rb:19:in `visitor'

Below is the gemlist

actionmailer (3.1.0.rc5)
actionpack (3.1.0.rc5)
activemodel (3.1.0.rc5)
activerecord (3.1.0.rc5)
activeresource (3.1.0.rc5)
activesupport (3.1.0.rc5)
ansi (1.3.0)
arel (2.1.5)
bcrypt-ruby (2.1.4)
builder (3.0.0)
bundler (1.0.17)
coffee-rails (3.1.0.rc.5)
coffee-script (2.2.0)
coffee-script-source (1.1.2)
erubis (2.7.0)
execjs (1.2.4)
hike (1.2.0)
i18n (0.6.0)
jquery-rails (1.0.12)
mail (2.3.0)
mime-types (1.16)
multi_json (1.0.3)
polyglot (0.3.2)
rack (1.3.2)
rack-cache (1.0.2)
rack-mount (0.8.1)
rack-ssl (1.3.2)
rack-test (0.6.1)
rails (3.1.0.rc5)
railties (3.1.0.rc5)
rake (0.9.2)
rdoc (3.9.1)
sass (3.1.7)
sass-rails (3.1.0.rc.5)
sprockets (2.0.0.beta.13)
sqlite3 (1.3.4)
thor (0.14.6)
tilt (1.3.2)
treetop (1.4.10)
turn (0.8.2)
tzinfo (0.3.29)
uglifier (1.0.0)

Answer 1

This is a bug in arel 2.1.5.

Fix this by adding gem "arel", "2.1.4" to your Gemfile and running bundle update arel.