# File lib/mechanize.rb, line 630
  def auth user, password, domain = nil
    caller.first =~ /(.*?):(\d+).*?$/

    warn "At \#{$1} line \#{$2}\n\nUse of #auth and #basic_auth are deprecated due to a security vulnerability.\n\n"

    @agent.add_default_auth user, password, domain
  end