# File lib/capybara/session.rb, line 55 def driver @driver ||= begin unless Capybara.drivers.has_key?(mode) other_drivers = Capybara.drivers.keys.map { |key| key.inspect } raise Capybara::DriverNotFoundError, "no driver called #{mode.inspect} was found, available drivers: #{other_drivers.join(', ')}" end Capybara.drivers[mode].call(app) end end