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: closing_issue_extractor.rb
    path of file: ./repos/gitlabhq/lib/gitlab
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

module Gitlab
  class ClosingIssueExtractor
    ISSUE_CLOSING_REGEX = begin
      link_pattern = Banzai::Filter::AutolinkFilter::LINK_PATTERN

      pattern = Gitlab.config
    
    def closed_by_message(message)
      return [] if message.nil?

      closing_statements = []
      message.scan(ISSUE_CLOSING_REGEX) do
        closing_statements << Regexp.last_match[0]
      end

      @extractor.analyze(closing_statements.join(" "))

      @extractor.issues.reject do |issue|
        @extractor.project.forked_from?(issue.project) ||
          !issue.project.autoclose_referenced_issues
      end
    end