Command history, tab completion and Rails SQL logs for script/console

.irbrc

# -*- mode: ruby -*-

# TAB completion for irb
require 'irb/completion'
ARGV.concat [ "--readline", "--prompt-mode", "simple" ]

# Save command history to be used between multiple sessions
require 'irb/ext/save-history'
IRB.conf[:SAVE_HISTORY] = 100
IRB.conf[:HISTORY_FILE] = "#{ENV['HOME']}/.irb-save-history"

# Output Rails logs to stdout when using script/console
script_console_running = ENV.include?('RAILS_ENV') && IRB.conf[:LOAD_MODULES] && IRB.conf[:LOAD_MODULES].include?('console_with_helpers')
rails_running = ENV.include?('RAILS_ENV') && !(IRB.conf[:LOAD_MODULES] && IRB.conf[:LOAD_MODULES].include?('console_with_helpers'))
irb_standalone_running = !script_console_running && !rails_running

if script_console_running
  require 'logger'
  Object.const_set(:RAILS_DEFAULT_LOGGER, Logger.new(STDOUT))
end