src/cobalt/black_box_tests/tests/preload_font.py

"""Open Cobalt in preload mode and find a basic element."""

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import time

import _env  # pylint: disable=unused-import

from cobalt.black_box_tests import black_box_tests

_MAX_RESUME_WAIT_SECONDS = 30


class PreloadFontTest(black_box_tests.BlackBoxTestCase):

  def test_simple(self):

    url = self.GetURL(file_name='preload_font.html')

    with self.CreateCobaltRunner(
        url=url, target_params=['--preload']) as runner:
      runner.WaitForJSTestsSetup()
      runner.SendResume()
      start_time = time.time()
      while runner.IsInPreload():
        if time.time() - start_time > _MAX_RESUME_WAIT_SECONDS:
          raise Exception('Cobalt can not exit preload mode after receiving'
                          'resume signal')
        time.sleep(.1)
      # At this point, Cobalt is in started mode.
      self.assertTrue(runner.JSTestsSucceeded())