tools/accessibility/nvda/nvda_chrome_tests.py

   1 #!/usr/bin/env python
   2 # Copyright 2014 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 """Semi-automated tests of Chrome with NVDA.
   7
   8 This file performs (semi) automated tests of Chrome with NVDA
   9 (NonVisual Desktop Access), a popular open-source screen reader for
  10 visually impaired users on Windows. It works by launching Chrome in a
  11 subprocess, then launching NVDA in a special environment that simulates
  12 speech rather than actually speaking, and ignores all events coming from
  13 processes other than a specific Chrome process ID. Each test automates
  14 Chrome with a series of actions and asserts that NVDA gives the expected
  15 feedback in response.
  16
  17 The tests are "semi" automated in the sense that they are not intended to be
  18 run from any developer machine, or on a buildbot - it requires setting up the
  19 environment according to the instructions in README.txt, then running the
  20 test script, then filing bugs for any potential failures. If the environment
  21 is set up correctly, the actual tests should run automatically and unattended.
  22 """
  23
  24 import os
  25 import pywinauto
  26 import re
  27 import shutil
  28 import signal
  29 import subprocess
  30 import sys
  31 import tempfile
  32 import time
  33 import unittest
  34
  35 CHROME_PROFILES_PATH = os.path.join(os.getcwd(), 'chrome_profiles')
  36 CHROME_PATH = os.path.join(os.environ['USERPROFILE'],
  37                            'AppData',
  38                            'Local',
  39                            'Google',
  40                            'Chrome SxS',
  41                            'Application',
  42                            'chrome.exe')
  43 NVDA_PATH = os.path.join(os.getcwd(),
  44                          'nvdaPortable',
  45                          'nvda_noUIAccess.exe')
  46 NVDA_PROCTEST_PATH = os.path.join(os.getcwd(),
  47                                   'nvda-proctest')
  48 NVDA_LOGPATH = os.path.join(os.getcwd(),
  49                             'nvda_log.txt')
  50 WAIT_FOR_SPEECH_TIMEOUT_SECS = 3.0
  51
  52 class NvdaChromeTest(unittest.TestCase):
  53   @classmethod
  54   def setUpClass(cls):
  55     print 'user data: %s' % CHROME_PROFILES_PATH
  56     print 'chrome: %s' % CHROME_PATH
  57     print 'nvda: %s' % NVDA_PATH
  58     print 'nvda_proctest: %s' % NVDA_PROCTEST_PATH
  59
  60     print
  61     print 'Clearing user data directory and log file from previous runs'
  62     if os.access(NVDA_LOGPATH, os.F_OK):
  63       os.remove(NVDA_LOGPATH)
  64     if os.access(CHROME_PROFILES_PATH, os.F_OK):
  65       shutil.rmtree(CHROME_PROFILES_PATH)
  66     os.mkdir(CHROME_PROFILES_PATH, 0777)
  67
  68     def handler(signum, frame):
  69       print 'Test interrupted, attempting to kill subprocesses.'
  70       self.tearDown()
  71       sys.exit()
  72     signal.signal(signal.SIGINT, handler)
  73
  74   def setUp(self):
  75     user_data_dir = tempfile.mkdtemp(dir = CHROME_PROFILES_PATH)
  76     args = [CHROME_PATH,
  77             '--user-data-dir=%s' % user_data_dir,
  78             '--no-first-run',
  79             'about:blank']
  80     print
  81     print ' '.join(args)
  82     self._chrome_proc = subprocess.Popen(args)
  83     self._chrome_proc.poll()
  84     if self._chrome_proc.returncode is None:
  85       print 'Chrome is running'
  86     else:
  87       print 'Chrome exited with code', self._chrome_proc.returncode
  88       sys.exit()
  89     print 'Chrome pid: %d' % self._chrome_proc.pid
  90
  91     os.environ['NVDA_SPECIFIC_PROCESS'] = str(self._chrome_proc.pid)
  92
  93     args = [NVDA_PATH,
  94             '-m',
  95             '-c',
  96             NVDA_PROCTEST_PATH,
  97             '-f',
  98             NVDA_LOGPATH]
  99     self._nvda_proc = subprocess.Popen(args)
 100     self._nvda_proc.poll()
 101     if self._nvda_proc.returncode is None:
 102       print 'NVDA is running'
 103     else:
 104       print 'NVDA exited with code', self._nvda_proc.returncode
 105       sys.exit()
 106     print 'NVDA pid: %d' % self._nvda_proc.pid
 107
 108     app = pywinauto.application.Application()
 109     app.connect_(process = self._chrome_proc.pid)
 110     self._pywinauto_window = app.top_window_()
 111
 112     try:
 113       self._WaitForSpeech(['Address and search bar edit', 'about:blank'])
 114     except:
 115       self.tearDown()
 116
 117   def tearDown(self):
 118     print
 119     print 'Shutting down'
 120
 121     self._chrome_proc.poll()
 122     if self._chrome_proc.returncode is None:
 123       print 'Killing Chrome subprocess'
 124       self._chrome_proc.kill()
 125     else:
 126       print 'Chrome already died.'
 127
 128     self._nvda_proc.poll()
 129     if self._nvda_proc.returncode is None:
 130       print 'Killing NVDA subprocess'
 131       self._nvda_proc.kill()
 132     else:
 133       print 'NVDA already died.'
 134
 135   def _GetSpeechFromNvdaLogFile(self):
 136     """Return everything NVDA would have spoken as a list of strings.
 137
 138     Parses lines like this from NVDA's log file:
 139       Speaking [LangChangeCommand ('en'), u'Google Chrome', u'window']
 140       Speaking character u'slash'
 141
 142     Returns a single list of strings like this:
 143       [u'Google Chrome', u'window', u'slash']
 144     """
 145     if not os.access(NVDA_LOGPATH, os.F_OK):
 146       return []
 147     lines = open(NVDA_LOGPATH).readlines()
 148     regex = re.compile(r"u'((?:[^\'\\]|\\.)*)\'")
 149     result = []
 150     for line in lines:
 151       for m in regex.finditer(line):
 152         speech_with_whitespace = m.group(1)
 153         speech_stripped = re.sub(r'\s+', ' ', speech_with_whitespace).strip()
 154         result.append(speech_stripped)
 155     return result
 156
 157   def _WaitForSpeech(self, expected):
 158     """Block until the last speech in NVDA's log file is the given string(s).
 159
 160     Repeatedly parses the log file until the last speech line(s) in the
 161     log file match the given strings, or it times out.
 162
 163     Args:
 164       expected: string or a list of string - only succeeds if these are the last
 165         strings spoken, in order.
 166
 167     Returns when those strings are spoken, or throws an error if it times out
 168       waiting for those strings.
 169     """
 170     if type(expected) is type(''):
 171       expected = [expected]
 172     start_time = time.time()
 173     while True:
 174       lines = self._GetSpeechFromNvdaLogFile()
 175       if (lines[-len(expected):] == expected):
 176         break
 177
 178       if time.time() - start_time >= WAIT_FOR_SPEECH_TIMEOUT_SECS:
 179         print '** Speech from NVDA so far:'
 180         for line in lines:
 181           print '"%s"' % line
 182         print '** Was waiting for:'
 183         for line in expected:
 184           print '"%s"' % line
 185         raise Exception('Timed out')
 186       time.sleep(0.1)
 187
 188   #
 189   # Tests
 190   #
 191
 192   def testTypingInOmnibox(self):
 193     # Ctrl+A: Select all.
 194     self._pywinauto_window.TypeKeys('^A')
 195     self._WaitForSpeech('selecting about:blank')
 196
 197     # Type three characters.
 198     self._pywinauto_window.TypeKeys('xyz')
 199     self._WaitForSpeech(['x', 'y', 'z'])
 200
 201     # Arrow back over two characters.
 202     self._pywinauto_window.TypeKeys('{LEFT}')
 203     self._WaitForSpeech(['z', 'z', 'unselecting'])
 204
 205     self._pywinauto_window.TypeKeys('{LEFT}')
 206     self._WaitForSpeech('y')
 207
 208   def testFocusToolbarButton(self):
 209     # Alt+Shift+T.
 210     self._pywinauto_window.TypeKeys('%+T')
 211     self._WaitForSpeech('Reload button Reload this page')
 212
 213   def testReadAllOnPageLoad(self):
 214     # Ctrl+A: Select all
 215     self._pywinauto_window.TypeKeys('^A')
 216     self._WaitForSpeech('selecting about:blank')
 217
 218     # Load data url.
 219     self._pywinauto_window.TypeKeys('data:text/html,Hello<p>World.')
 220     self._WaitForSpeech('dot')
 221     self._pywinauto_window.TypeKeys('{ENTER}')
 222     self._WaitForSpeech(
 223         ['document',
 224          'Hello',
 225          'World.'])
 226
 227 if __name__ == '__main__':
 228   unittest.main()
 229