module Concourse::Util

def ensure_in_gitignore file_glob
  if File.exist?(GITIGNORE_FILE)
    if File.read(GITIGNORE_FILE).split("\n").include?(file_glob)
      note "found '#{file_glob}' already present in #{GITIGNORE_FILE}"
      return
    end
  end
  note "adding '#{file_glob}' to #{GITIGNORE_FILE}"
  File.open(GITIGNORE_FILE, "a") { |f| f.puts file_glob }
end