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: incompatibility.rb
    path of file: ./repos/ruby/lib/bundler/vendor/pub_grub/lib/pub_grub
    
    the code of the file until where you have to start completion: module Bundler::PubGrub
  class Inc
    
    def external_incompatibilities
      if conflict?
        [
          cause.conflict,
          cause.other
        ].flat_map(&:external_incompatibilities)
      else
        [this]
      end