You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: collector.rb
    path of file: ./repos/stackneveroverflow/vendor/bundle/ruby/2.3.0/gems/actionpack-5.0.3/lib/abstract_controller
    
    the code of the file until where you have to start completion: require "action_dispatch/http/mime_type
    
    def method_missing(symbol, &block)
      unless mime_constant = Mime[symbol]
        raise NoMethodError, "To respond to a custom format, register it as a MIME type first: " \
          "http://guides.rubyonrails.org/action_controller_overview.html#restful-downloads. " \
          "If you meant to respond to a variant like :tablet or :phone, not a custom format, " \
          "be sure to nest your variant response within a format response: " \
          "format.html { |html| html.tablet { ... } }"
      end