class ActionDispatch::Routing::Mapper::Mapping

def normalize_path(path)
  raise ArgumentError, "path is required" if path.blank?
  path = Mapper.normalize_path(path)
  if path.match(':controller')
    raise ArgumentError, ":controller segment is not allowed within a namespace block" if @scope[:module]
    # Add a default constraint for :controller path segments that matches namespaced
    # controllers with default routes like :controller/:action/:id(.:format), e.g:
    # GET /admin/products/show/1
    # => { :controller => 'admin/products', :action => 'show', :id => '1' }
    @options.reverse_merge!(:controller => /.+?/)
  end
  if @options[:format] == false
    @options.delete(:format)
    path
  elsif path.include?(":format")
    path
  else
    "#{path}(.:format)"
  end
end