Tddium post-build task to deploy into Heroku and notify New Relic

tddium_post_build.rake

def cmd(c)
  system c
end

namespace :tddium do
  desc "post_build_hook"
  task :post_build_hook do
    # This build hook should only run after CI builds.
    #
    # There are other cases where we'd want to run something after every build,
    # or only after manual builds.
    return unless ENV["TDDIUM_MODE"] == "ci"
    return unless ENV["TDDIUM_BUILD_STATUS"] == "passed"

    dir = File.expand_path("~/.heroku/")
    heroku_email = ENV["HEROKU_EMAIL"]
    heroku_api_key = ENV["HEROKU_API_KEY"]
    current_branch = `git symbolic-ref HEAD 2>/dev/null | cut -d"/" -f 3-`.strip
    app_name = ENV["HEROKU_APP_NAME"]
    push_target = "git@heroku.com:#{app_name}.git"

    abort "invalid current branch" unless current_branch

    FileUtils.mkdir_p(dir) or abort "Could not create #{dir}"

    puts "Writing Heroku Credentials"
    File.open(File.join(dir, "credentials"), "w") do |f|
      f.write([heroku_email, heroku_api_key].join("\n"))
      f.write("\n")
    end

    File.open(File.expand_path("~/.netrc"), "a+") do |f|
      ['api', 'code'].each do |host|
        f.puts "machine #{host}.heroku.com"
        f.puts "  login #{heroku_email}"
        f.puts "  password #{heroku_api_key}"
      end
    end

    puts "Pushing to Heroku: #{push_target}..."
    cmd "git push #{push_target} HEAD:master --force" or abort "could not push to #{push_target}"

    Bundler.with_clean_env do
      puts "Running Heroku Migrations..."
      cmd "heroku run rake db:migrate --app #{app_name}" or abort "aborted migrations"

      puts "Restarting Heroku..."
      cmd "heroku restart --app #{app_name}" or abort "aborted heroku restart"
    end
  end
end

The Gist description says it "notifies New Relic" and this page is linked from the Solano help site but there's no reference to New Relic in the code. Does this assume that Heroku is notifying New Relic? Or is something missing in the code? Or is the description just wrong?

The New Relic notification was removed in a previous version; you can see it by looking at the revision history here. A new version will be posted.