class ActionDispatch::Cookies::CookieJar

def []=(name, options)

value or a hash of options as documented above.
Sets the cookie named +name+. The second argument may be the cookie's
def []=(name, options)
  if options.is_a?(Hash)
    options.symbolize_keys!
    value = options[:value]
  else
    value = options
    options = { value: value }
  end
  handle_options(options)
  if @cookies[name.to_s] != value || options[:expires]
    @cookies[name.to_s] = value
    @set_cookies[name.to_s] = options
    @delete_cookies.delete(name.to_s)
  end
  value
end