Old style environment.rb referenced this method directly. Please note, it doesn’t actually do anything any more.
# File activesupport/lib/active_support/dependencies.rb, line 399 def self.root(*args) if defined?(RAILS_DEFAULT_LOGGER) RAILS_DEFAULT_LOGGER.warn "Your environment.rb uses the old syntax, it may not continue to work in future releases." RAILS_DEFAULT_LOGGER.warn "For upgrade instructions please see: http://manuals.rubyonrails.com/read/book/19" end end