class Capybara::Helpers::Timer

def current
  Capybara::Helpers.monotonic_time
end

def expired?
  if stalled?
    raise Capybara::FrozenInTime, 'Time appears to be frozen. Capybara does not work with libraries which freeze time, consider using time travelling instead'
  end
  current - @start >= @expire_in
end

def initialize(expire_in)
  @start = current
  @expire_in = expire_in
end

def stalled?
  @start == current
end