tools/perf/measurements/screenshot_unittest.py

# Copyright 2014 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import logging
import shutil
import tempfile

from measurements import screenshot
from telemetry.page import page_measurement_unittest_base
from telemetry.page import page_test
from telemetry.unittest import options_for_unittests


class ScreenshotUnitTest(
      page_measurement_unittest_base.PageMeasurementUnitTestBase):
  def setUp(self):
    self._options = options_for_unittests.GetCopy()
    self._options.png_outdir = tempfile.mkdtemp('_png_test')

  def tearDown(self):
    shutil.rmtree(self._options.png_outdir)

  def testScreenshot(self):
    ps = self.CreatePageSetFromFileInUnittestDataDir('blank.html')
    measurement = screenshot.Screenshot()
    try:
      results = self.RunMeasurement(measurement, ps, options=self._options)
    except page_test.TestNotSupportedOnPlatformFailure as failure:
      logging.warning(str(failure))
      return

    saved_picture_count = results.FindAllPageSpecificValuesNamed(
        'saved_picture_count')
    self.assertEquals(len(saved_picture_count), 1)
    self.assertGreater(saved_picture_count[0].GetRepresentativeNumber(), 0)