write_inheritable_array

# File activesupport/lib/active_support/core_ext/class/inheritable_attributes.rb, line 139
  def write_inheritable_array(key, elements)
    write_inheritable_attribute(key, []) if read_inheritable_attribute(key).nil?
    write_inheritable_attribute(key, read_inheritable_attribute(key) + elements)
  end