text: from __future__ import unicode_literals
  
  import multiprocessing
  import threading
  import traceback
  from six.moves.queue import Empty
  from collections import namedtuple
  from multiprocessing import Process, current_process, Queue
  
  from mozlog import structuredlog, capture
  
  # Special value used as a sentinal in various commands
  Stop = object()
  
  
  def release_mozlog_lock():
      try:
          from mozlog.structuredlog import StructuredLogger
          try:
              StructuredLogger._lock.release()
          except threading.ThreadError:
              pass
      except ImportError:
          pass
  
  
  class MessageLogger(object):
      def __init__(self, message_func):
          self.send_message = message_func
  
      def _log_data(self, action, **kwargs):
          self.send_message("log", action, kwargs)
  
      def process_output(self, process, data, command):
          self._log_data("process_output", process=process, data=data, command=command)
  
  
  def _log_func(level_name):
      def log(self, message):
          self._log_data(level_name.lower(), message=message)
      log.__doc__ = """Log a message with level %s
  
  :param message: The string message to log
  """ % level_name
      log.__name__ = str(level_name).lower()
      return log
  
  # Create all the methods on StructuredLog for debug levels
  for level_name in structuredlog.log_levels:
      setattr(MessageLogger, level_name.lower(), _log_func(level_name))
  
  
  class TestRunner(object):
      """Class implementing the main loop for running tests.
  
      This class delegates the job of actually running a test to the executor
      that is passed in.
  
      :param logger: Structured logger
      :param command_queue: subprocess.Queue used to send commands to the
                            process
      :param result_queue: subprocess.Queue used to send results to the
                           parent TestRunnerManager process
      :param executor: TestExecutor object that will actually run a test.
      """
      def __init__(self, logger, command_queue, result_queue, executor):
          self.command_queue = command_queue
          self.result_queue = result_queue
  
          self.executor = executor
          self.name = current_process().name
          self.logger = logger
  
      def __enter__(self):
          return self
  
      def __exit__(self, exc_type, exc_value, traceback):
          self.teardown()
  
      def setup(self):
          self.logger.debug("Executor setup")
          try:
              self.executor.setup(self)
          except Exception:
              # The caller is responsible for logging the exception if required
              self.send_message("init_failed")
          else:
              self.send_message("init_succeeded")
          self.logger.debug("Executor setup done")
  
      def teardown(self):
          self.executor.teardown()
          self.send_message("runner_teardown")
          self.result_queue = None
          self.command_queue = None
          self.browser = None
  
      def run(self):
          """Main loop accepting commands over the pipe and triggering
          the associated methods"""
          try:
              self.setup()
          except Exception:
              self.logger.warning("An error occured during executor setup:\n%s" %
                                  traceback.format_exc())
              raise
          commands = {"run_test": self.run_test,
                      "reset": self.reset,
                      "stop": self.stop,
                      "wait": self.wait}
          while True:
              command, args = self.command_queue.get()
              try:
                  rv = commands[command](*args)
              except Exception:
                  self.send_message("error",
                                    "Error running command %s with arguments %r:\n%s" %
                                    (command, args, traceback.format_exc()))
              else:
                  if rv is Stop:
                      break
  
      def stop(self):
          return Stop
  
      def reset(self):
          self.executor.reset()
  
      def run_test(self, test):
          try:
              return self.executor.run_test(test)
          except Exception:
              self.logger.error(traceback.format_exc())
              raise
  
      def wait(self):
          self.executor.wait()
          self.send_message("wait_finished")
  
      def send_message(self, command, *args):
          self.result_queue.put((command, args))
  
  
  def start_runner(runner_command_queue, runner_result_queue,
                   executor_cls, executor_kwargs,
                   executor_browser_cls, executor_browser_kwargs,
                   capture_stdio, stop_flag):
      """Launch a TestRunner in a new process"""
  
      def send_message(command, *args):
          runner_result_queue.put((command, args))
  
      def handle_error(e):
          logger.critical(traceback.format_exc())
          stop_flag.set()
  
      # Ensure that when we start this in a new process we have the global lock
      # in the logging module unlocked
      release_mozlog_lock()
  
      logger = MessageLogger(send_message)
  
      with capture.CaptureIO(logger, capture_stdio):
          try:
              browser = executor_browser_cls(**executor_browser_kwargs)
              executor = executor_cls(logger, browser, **executor_kwargs)
              with TestRunner(logger, runner_command_queue, runner_result_queue, executor) as runner:
                  try:
                      runner.run()
                  except KeyboardInterrupt:
                      stop_flag.set()
                  except Exception as e:
                      handle_error(e)
          except Exception as e:
              handle_error(e)
  
  
  manager_count = 0
  
  
  def next_manager_number():
      global manager_count
      local = manager_count = manager_count + 1
      return local
  
  
  class BrowserManager(object):
      def __init__(self, logger, browser, command_queue, no_timeout=False):
          self.logger = logger
          self.browser = browser
          self.no_timeout = no_timeout
          self.browser_settings = None
          self.last_test = None
  
          self.started = False
  
          self.init_timer = None
          self.command_queue = command_queue
  
      def update_settings(self, test):
          browser_settings = self.browser.settings(test)
          restart_required = ((self.browser_settings is not None and
                               self.browser_settings != browser_settings) or
                              (self.last_test != test and test.expected() == "CRASH"))
          self.browser_settings = browser_settings
          self.last_test = test
          return restart_required
  
      def init(self, group_metadata):
          """Launch the browser that is being tested,
          and the TestRunner process that will run the tests."""
          # It seems that this lock is helpful to prevent some race that otherwise
          # sometimes stops the spawned processes initialising correctly, and
          # leaves this thread hung
          if self.init_timer is not None:
              self.init_timer.cancel()
  
          self.logger.debug("Init called, starting browser and runner")
  
          if not self.no_timeout:
              self.init_timer = threading.Timer(self.browser.init_timeout,
                                                self.init_timeout)
          try:
              if self.init_timer is not None:
                  self.init_timer.start()
              self.logger.debug("Starting browser with settings %r" % self.browser_settings)
              self.browser.start(group_metadata=group_metadata, **self.browser_settings)
              self.browser_pid = self.browser.pid()
          except Exception:
              self.logger.warning("Failure during init %s" % traceback.format_exc())
              if self.init_timer is not None:
                  self.init_timer.cancel()
              self.logger.error(traceback.format_exc())
              succeeded = False
          else:
              succeeded = True
              self.started = True
  
          return succeeded
  
      def send_message(self, command, *args):
          self.command_queue.put((command, args))
  
      def init_timeout(self):
          # This is called from a separate thread, so we send a message to the
          # main loop so we get back onto the manager thread
          self.logger.debug("init_failed called from timer")
          self.send_message("init_failed")
  
      def after_init(self):
          """Callback when we have started the browser, started the remote
          control connection, and we are ready to start testing."""
          if self.init_timer is not None:
              self.init_timer.cancel()
  
      def stop(self, force=False):
          self.browser.stop(force=force)
          self.started = False
  
      def cleanup(self):
          if self.init_timer is not None:
              self.init_timer.cancel()
  
      def check_crash(self, test_id):
          return self.browser.check_crash(process=self.browser_pid, test=test_id)
  
      def is_alive(self):
          return self.browser.is_alive()
  
  
  class _RunnerManagerState(object):
      before_init = namedtuple("before_init", [])
      initializing = namedtuple("initializing_browser",
                                ["test", "test_group", "group_metadata", "failure_count"])
      running = namedtuple("running", ["test", "test_group", "group_metadata"])
      restarting = namedtuple("restarting", ["test", "test_group", "group_metadata"])
      error = namedtuple("error", [])
      stop = namedtuple("stop", [])
  
  
  RunnerManagerState = _RunnerManagerState()
  
  
  class TestRunnerManager(threading.Thread):
      def __init__(self, suite_name, test_queue, test_source_cls, browser_cls, browser_kwargs,
                   executor_cls, executor_kwargs, stop_flag, rerun=1, pause_after_test=False,
                   pause_on_unexpected=False, restart_on_unexpected=True, debug_info=None,
                   capture_stdio=True, recording=None):
          """Thread that owns a single TestRunner process and any processes required
          by the TestRunner (e.g. the Firefox binary).
  
          TestRunnerManagers are responsible for launching the browser process and the
          runner process, and for logging the test progress. The actual test running
          is done by the TestRunner. In particular they:
  
          * Start the binary of the program under test
          * Start the TestRunner
          * Tell the TestRunner to start a test, if any
          * Log that the test started
          * Log the test results
          * Take any remedial action required e.g. restart crashed or hung
            processes
          """
          self.suite_name = suite_name
  
          self.test_source = test_source_cls(test_queue)
  
          self.browser_cls = browser_cls
          self.browser_kwargs = browser_kwargs
  
          self.executor_cls = executor_cls
          self.executor_kwargs = executor_kwargs
  
          # Flags used to shut down this thread if we get a sigint
          self.parent_stop_flag = stop_flag
          self.child_stop_flag = multiprocessing.Event()
  
          self.rerun = rerun
          self.run_count = 0
          self.pause_after_test = pause_after_test
          self.pause_on_unexpected = pause_on_unexpected
          self.restart_on_unexpected = restart_on_unexpected
          self.debug_info = debug_info
  
          self.manager_number = next_manager_number()
          assert recording is not None
          self.recording = recording
  
          self.command_queue = Queue()
          self.remote_queue = Queue()
  
          self.test_runner_proc = None
  
          threading.Thread.__init__(self, name="TestRunnerManager-%i" % self.manager_number)
          # This is started in the actual new thread
          self.logger = None
  
          self.test_count = 0
          self.unexpected_count = 0
  
          # This may not really be what we want
          self.daemon = True
  
          self.timer = None
  
          self.max_restarts = 5
  
          self.browser = None
  
          self.capture_stdio = capture_stdio
  
      def run(self):
          """Main loop for the TestRunnerManager.
  
          TestRunnerManagers generally receive commands from their
          TestRunner updating them on the status of a test. They
          may also have a stop flag set by the main thread indicating
          that the manager should shut down the next time the event loop
          spins."""
          self.recording.set(["testrunner", "startup"])
          self.logger = structuredlog.StructuredLogger(self.suite_name)
          with self.browser_cls(self.logger, **self.browser_kwargs) as browser:
              self.browser = BrowserManager(self.logger,
                                            browser,
                                            self.command_queue,
                                            no_timeout=self.debug_info is not None)
              dispatch = {
                  RunnerManagerState.before_init: self.start_init,
                  RunnerManagerState.initializing: self.init,
                  RunnerManagerState.running: self.run_test,
                  RunnerManagerState.restarting: self.restart_runner
              }
  
              self.state = RunnerManagerState.before_init()
              end_states = (RunnerManagerState.stop,
                            RunnerManagerState.error)
  
              try:
                  while not isinstance(self.state, end_states):
                      f = dispatch.get(self.state.__class__)
                      while f:
                          self.logger.debug("Dispatch %s" % f.__name__)
                          if self.should_stop():
                              return
                          new_state = f()
                          if new_state is None:
                              break
                          self.state = new_state
                          self.logger.debug("new state: %s" % self.state.__class__.__name__)
                          if isinstance(self.state, end_states):
                              return
                          f = dispatch.get(self.state.__class__)
  
                      new_state = None
                      while new_state is None:
                          new_state = self.wait_event()
                          if self.should_stop():
                              return
                      self.state = new_state
                      self.logger.debug("new state: %s" % self.state.__class__.__name__)
              except Exception:
                  self.logger.error(traceback.format_exc())
                  raise
              finally:
                  self.logger.debug("TestRunnerManager main loop terminating, starting cleanup")
                  clean = isinstance(self.state, RunnerManagerState.stop)
                  self.stop_runner(force=not clean)
                  self.teardown()
          self.logger.debug("TestRunnerManager main loop terminated")
  
      def wait_event(self):
          dispatch = {
              RunnerManagerState.before_init: {},
              RunnerManagerState.initializing:
              {
                  "init_succeeded": self.init_succeeded,
                  "init_failed": self.init_failed,
              },
              RunnerManagerState.running:
              {
                  "test_ended": self.test_ended,
                  "wait_finished": self.wait_finished,
              },
              RunnerManagerState.restarting: {},
              RunnerManagerState.error: {},
              RunnerManagerState.stop: {},
              None: {
                  "runner_teardown": self.runner_teardown,
                  "log": self.log,
                  "error": self.error
              }
          }
          try:
              command, data = self.command_queue.get(True, 1)
              self.logger.debug("Got command: %r" % command)
          except IOError:
              self.logger.error("Got IOError from poll")
              return RunnerManagerState.restarting(0)
          except Empty:
              if (self.debug_info and self.debug_info.interactive and
                  self.browser.started and not self.browser.is_alive()):
                  self.logger.debug("Debugger exited")
                  return RunnerManagerState.stop()
  
              if (isinstance(self.state, RunnerManagerState.running) and
                  not self.test_runner_proc.is_alive()):
                  if not self.command_queue.empty():
                      # We got a new message so process that
                      return
  
                  # If we got to here the runner presumably shut down
                  # unexpectedly
                  self.logger.info("Test runner process shut down")
  
                  if self.state.test is not None:
                      # This could happen if the test runner crashed for some other
                      # reason
                      # Need to consider the unlikely case where one test causes the
                      # runner process to repeatedly die
                      self.logger.critical("Last test did not complete")
                      return RunnerManagerState.error()
                  self.logger.warning("More tests found, but runner process died, restarting")
                  return RunnerManagerState.restarting(0)
          else:
              f = (dispatch.get(self.state.__class__, {}).get(command) or
                   dispatch.get(None, {}).get(command))
              if not f:
                  self.logger.warning("Got command %s in state %s" %
                                      (command, self.state.__class__.__name__))
                  return
              return f(*data)
  
      def should_stop(self):
          return self.child_stop_flag.is_set() or self.parent_stop_flag.is_set()
  
      def start_init(self):
          test, test_group, group_metadata = self.get_next_test()
          self.recording.set(["testrunner", "init"])
          if test is None:
              return RunnerManagerState.stop()
          else:
              return RunnerManagerState.initializing(test, test_group, group_metadata, 0)
  
      def init(self):
          assert isinstance(self.state, RunnerManagerState.initializing)
          if self.state.failure_count > self.max_restarts:
              self.logger.critical("Max restarts exceeded")
              return RunnerManagerState.error()
  
          self.browser.update_settings(self.state.test)
  
          result = self.browser.init(self.state.group_metadata)
          if result is Stop:
              return RunnerManagerState.error()
          elif not result:
              return RunnerManagerState.initializing(self.state.test,
                                                     self.state.test_group,
                                                     self.state.group_metadata,
                                                     self.state.failure_count + 1)
          else:
              self.executor_kwargs["group_metadata"] = self.state.group_metadata
              self.start_test_runner()
  
      def start_test_runner(self):
          # Note that we need to be careful to start the browser before the
          # test runner to ensure that any state set when the browser is started
          # can be passed in to the test runner.
          assert isinstance(self.state, RunnerManagerState.initializing)
          assert self.command_queue is not None
          assert self.remote_queue is not None
          self.logger.info("Starting runner")
          executor_browser_cls, executor_browser_kwargs = self.browser.browser.executor_browser()
  
          args = (self.remote_queue,
                  self.command_queue,
                  self.executor_cls,
                  self.executor_kwargs,
                  executor_browser_cls,
                  executor_browser_kwargs,
                  self.capture_stdio,
                  self.child_stop_flag)
          self.test_runner_proc = Process(target=start_runner,
                                          args=args,
                                          name="TestRunner-%i" % self.manager_number)
          self.test_runner_proc.start()
          self.logger.debug("Test runner started")
          # Now we wait for either an init_succeeded event or an init_failed event
  
      def init_succeeded(self):
          assert isinstance(self.state, RunnerManagerState.initializing)
          self.browser.after_init()
          return RunnerManagerState.running(self.state.test,
                                            self.state.test_group,
                                            self.state.group_metadata)
  
      def init_failed(self):
          assert isinstance(self.state, RunnerManagerState.initializing)
          self.browser.check_crash(None)
          self.browser.after_init()
          self.stop_runner(force=True)
          return RunnerManagerState.initializing(self.state.test,
                                                 self.state.test_group,
                                                 self.state.group_metadata,
                                                 self.state.failure_count + 1)
  
      def get_next_test(self, test_group=None):
          test = None
          while test is None:
              while test_group is None or len(test_group) == 0:
                  test_group, group_metadata = self.test_source.group()
                  if test_group is None:
                      self.logger.info("No more tests")
                      return None, None, None
              test = test_group.popleft()
          self.run_count = 0
          return test, test_group, group_metadata
  
      def run_test(self):
          assert isinstance(self.state, RunnerManagerState.running)
          assert self.state.test is not None
  
          if self.browser.update_settings(self.state.test):
              self.logger.info("Restarting browser for new test environment")
              return RunnerManagerState.restarting(self.state.test,
                                                   self.state.test_group,
                                                   self.state.group_metadata)
  
          self.recording.set(["testrunner", "test"] + self.state.test.id.split("/")[1:])
          self.logger.test_start(self.state.test.id)
          if self.rerun > 1:
              self.logger.info("Run %d/%d" % (self.run_count, self.rerun))
              self.send_message("reset")
          self.run_count += 1
          if self.debug_info is None:
              # Factor of 3 on the extra timeout here is based on allowing the executor
              # at least test.timeout + 2 * extra_timeout to complete,
              # which in turn is based on having several layers of timeout inside the executor
              wait_timeout = (self.state.test.timeout * self.executor_kwargs['timeout_multiplier'] +
                              3 * self.executor_cls.extra_timeout)
              self.timer = threading.Timer(wait_timeout, self._timeout)
  
          self.send_message("run_test", self.state.test)
          if self.timer:
              self.timer.start()
  
      def _timeout(self):
          # This is executed in a different thread (threading.Timer).
          self.logger.info("Got timeout in harness")
          test = self.state.test
          self.inject_message(
              "test_ended",
              test,
              (test.result_cls("EXTERNAL-TIMEOUT",
                               "TestRunner hit external timeout "
                               "(this may indicate a hang)"), []),
          )
  
      def test_ended(self, test, results):
          """Handle the end of a test.
  
          Output the result of each subtest, and the result of the overall
          harness to the logs.
          """
          if ((not isinstance(self.state, RunnerManagerState.running)) or
              (test != self.state.test)):
              # Due to inherent race conditions in EXTERNAL-TIMEOUT, we might
              # receive multiple test_ended for a test (e.g. from both Executor
              # and TestRunner), in which case we ignore the duplicate message.
              self.logger.error("Received unexpected test_ended for %s" % test)
              return
          if self.timer is not None:
              self.timer.cancel()
          # Write the result of each subtest
          file_result, test_results = results
          subtest_unexpected = False
          expect_any_subtest_status = test.expect_any_subtest_status()
          if expect_any_subtest_status:
              self.logger.debug("Ignoring subtest statuses for test %s" % test.id)
          for result in test_results:
              if test.disabled(result.name):
                  continue
              if expect_any_subtest_status:
                  expected = result.status
              else:
                  expected = test.expected(result.name)
              known_intermittent = test.known_intermittent(result.name)
              is_unexpected = expected != result.status and result.status not in known_intermittent
  
              if is_unexpected:
                  self.unexpected_count += 1
                  self.logger.debug("Unexpected count in this thread %i" % self.unexpected_count)
                  subtest_unexpected = True
              self.logger.test_status(test.id,
                                      result.name,
                                      result.status,
                                      message=result.message,
                                      expected=expected,
                                      known_intermittent=known_intermittent,
                                      stack=result.stack)
  
          # We have a couple of status codes that are used internally, but not exposed to the
          # user. These are used to indicate that some possibly-broken state was reached
          # and we should restart the runner before the next test.
          # INTERNAL-ERROR indicates a Python exception was caught in the harness
          # EXTERNAL-TIMEOUT indicates we had to forcibly kill the browser from the harness
          # because the test didn't return a result after reaching the test-internal timeout
          status_subns = {"INTERNAL-ERROR": "ERROR",
                          "EXTERNAL-TIMEOUT": "TIMEOUT"}
          expected = test.expected()
          known_intermittent = test.known_intermittent()
          status = status_subns.get(file_result.status, file_result.status)
  
          if self.browser.check_crash(test.id) and status != "CRASH":
              if test.test_type == "crashtest":
                  self.logger.info("Found a crash dump file; changing status to CRASH")
                  status = "CRASH"
              else:
                  self.logger.warning("Found a crash dump; should change status from %s to CRASH but this causes instability" % (status,))
  
          self.test_count += 1
          is_unexpected = expected != status and status not in known_intermittent
          if is_unexpected:
              self.unexpected_count += 1
              self.logger.debug("Unexpected count in this thread %i" % self.unexpected_count)
  
          if "assertion_count" in file_result.extra:
              assertion_count = file_result.extra.pop("assertion_count")
              if assertion_count > 0:
                  self.logger.assertion_count(test.id,
                                              int(assertion_count),
                                              test.min_assertion_count,
                                              test.max_assertion_count)
  
          file_result.extra["test_timeout"] = test.timeout * self.executor_kwargs['timeout_multiplier']
  
          self.logger.test_end(test.id,
                               status,
                               message=file_result.message,
                               expected=expected,
                               known_intermittent=known_intermittent,
                               extra=file_result.extra,
                               stack=file_result.stack)
  
          restart_before_next = (test.restart_after or
                                 file_result.status in ("CRASH", "EXTERNAL-TIMEOUT", "INTERNAL-ERROR") or
                                 ((subtest_unexpected or is_unexpected) and
                                  self.restart_on_unexpected))
  
          self.recording.set(["testrunner", "after-test"])
          if (not file_result.status == "CRASH" and
              self.pause_after_test or
              (self.pause_on_unexpected and (subtest_unexpected or is_unexpected))):
              self.logger.info("Pausing until the browser exits")
              self.send_message("wait")
          else:
              return self.after_test_end(test, restart_before_next)
  
      def wait_finished(self):
          assert isinstance(self.state, RunnerManagerState.running)
          self.logger.debug("Wait finished")
  
          # The browser should be stopped already, but this ensures we do any
          # post-stop processing
          return self.after_test_end(self.state.test, True)
  
      def after_test_end(self, test, restart):
          assert isinstance(self.state, RunnerManagerState.running)
          if self.run_count == self.rerun:
              test, test_group, group_metadata = self.get_next_test()
              if test is None:
                  return RunnerManagerState.stop()
              if test_group is not self.state.test_group:
                  # We are starting a new group of tests, so force a restart
                  self.logger.info("Restarting browser for new test group")
                  restart = True
          else:
              test_group = self.state.test_group
              group_metadata = self.state.group_metadata
          if restart:
              return RunnerManagerState.restarting(test, test_group, group_metadata)
          else:
              return RunnerManagerState.running(test, test_group, group_metadata)
  
      def restart_runner(self):
          """Stop and restart the TestRunner"""
          assert isinstance(self.state, RunnerManagerState.restarting)
          self.stop_runner()
          return RunnerManagerState.initializing(self.state.test, self.state.test_group, self.state.group_metadata, 0)
  
      def log(self, action, kwargs):
          getattr(self.logger, action)(**kwargs)
  
      def error(self, message):
          self.logger.error(message)
          self.restart_runner()
  
      def stop_runner(self, force=False):
          """Stop the TestRunner and the browser binary."""
          self.recording.set(["testrunner", "stop_runner"])
          if self.test_runner_proc is None:
              return
  
          if self.test_runner_proc.is_alive():
              self.send_message("stop")
          try:
              self.browser.stop(force=force)
              self.ensure_runner_stopped()
          finally:
              self.cleanup()
  
      def teardown(self):
          self.logger.debug("TestRunnerManager teardown")
          self.test_runner_proc = None
          self.command_queue.close()
          self.remote_queue.close()
          self.command_queue = None
          self.remote_queue = None
          self.recording.pause()
  
      def ensure_runner_stopped(self):
          self.logger.debug("ensure_runner_stopped")
          if self.test_runner_proc is None:
              return
  
          self.browser.stop(force=True)
          self.logger.debug("waiting for runner process to end")
          self.test_runner_proc.join(10)
          self.logger.debug("After join")
          if self.test_runner_proc.is_alive():
              # This might leak a file handle from the queue
              self.logger.warning("Forcibly terminating runner process")
              self.test_runner_proc.terminate()
  
              # Multiprocessing queues are backed by operating system pipes. If
              # the pipe in the child process had buffered data at the time of
              # forced termination, the queue is no longer in a usable state
              # (subsequent attempts to retrieve items may block indefinitely).
              # Discard the potentially-corrupted queue and create a new one.
              self.command_queue.close()
              self.command_queue = Queue()
              self.remote_queue.close()
              self.remote_queue = Queue()
          else:
              self.logger.debug("Runner process exited with code %i" % self.test_runner_proc.exitcode)
  
      def runner_teardown(self):
          self.ensure_runner_stopped()
          return RunnerManagerState.stop()
  
      def send_message(self, command, *args):
          """Send a message to the remote queue (to Executor)."""
          self.remote_queue.put((command, args))
  
      def inject_message(self, command, *args):
          """Inject a message to the command queue (from Executor)."""
          self.command_queue.put((command, args))
  
      def cleanup(self):
          self.logger.debug("TestRunnerManager cleanup")
          if self.browser:
              self.browser.cleanup()
          while True:
              try:
                  cmd, data = self.command_queue.get_nowait()
              except Empty:
                  break
              else:
                  if cmd == "log":
                      self.log(*data)
                  elif cmd == "runner_teardown":
                      # It's OK for the "runner_teardown" message to be left in
                      # the queue during cleanup, as we will already have tried
                      # to stop the TestRunner in `stop_runner`.
                      pass
                  else:
                      self.logger.warning("Command left in command_queue during cleanup: %r, %r" % (cmd, data))
          while True:
              try:
                  cmd, data = self.remote_queue.get_nowait()
                  self.logger.warning("Command left in remote_queue during cleanup: %r, %r" % (cmd, data))
              except Empty:
                  break
  
  
  def make_test_queue(tests, test_source_cls, **test_source_kwargs):
      queue = test_source_cls.make_queue(tests, **test_source_kwargs)
  
      # There is a race condition that means sometimes we continue
      # before the tests have been written to the underlying pipe.
      # Polling the pipe for data here avoids that
      queue._reader.poll(10)
      assert not queue.empty()
      return queue
  
  
  class ManagerGroup(object):
      """Main thread object that owns all the TestRunnerManager threads."""
      def __init__(self, suite_name, size, test_source_cls, test_source_kwargs,
                   browser_cls, browser_kwargs,
                   executor_cls, executor_kwargs,
                   rerun=1,
                   pause_after_test=False,
                   pause_on_unexpected=False,
                   restart_on_unexpected=True,
                   debug_info=None,
                   capture_stdio=True,
                   recording=None):
          self.suite_name = suite_name
          self.size = size
          self.test_source_cls = test_source_cls
          self.test_source_kwargs = test_source_kwargs
          self.browser_cls = browser_cls
          self.browser_kwargs = browser_kwargs
          self.executor_cls = executor_cls
          self.executor_kwargs = executor_kwargs
          self.pause_after_test = pause_after_test
          self.pause_on_unexpected = pause_on_unexpected
          self.restart_on_unexpected = restart_on_unexpected
          self.debug_info = debug_info
          self.rerun = rerun
          self.capture_stdio = capture_stdio
          self.recording = recording
          assert recording is not None
  
          self.pool = set()
          # Event that is polled by threads so that they can gracefully exit in the face
          # of sigint
          self.stop_flag = threading.Event()
          self.logger = structuredlog.StructuredLogger(suite_name)
  
      def __enter__(self):
          return self
  
      def __exit__(self, exc_type, exc_val, exc_tb):
          self.stop()
  
      def run(self, test_type, tests):
          """Start all managers in the group"""
          self.logger.debug("Using %i processes" % self.size)
          type_tests = tests[test_type]
          if not type_tests:
              self.logger.info("No %s tests to run" % test_type)
              return
  
          test_queue = make_test_queue(type_tests, self.test_source_cls, **self.test_source_kwargs)
  
          for _ in range(self.size):
              manager = TestRunnerManager(self.suite_name,
                                          test_queue,
                                          self.test_source_cls,
                                          self.browser_cls,
                                          self.browser_kwargs,
                                          self.executor_cls,
                                          self.executor_kwargs,
                                          self.stop_flag,
                                          self.rerun,
                                          self.pause_after_test,
                                          self.pause_on_unexpected,
                                          self.restart_on_unexpected,
                                          self.debug_info,
                                          self.capture_stdio,
                                          recording=self.recording)
              manager.start()
              self.pool.add(manager)
          self.wait()
  
      def wait(self):
          """Wait for all the managers in the group to finish"""
          for manager in self.pool:
              manager.join()
  
      def stop(self):
          """Set the stop flag so that all managers in the group stop as soon
          as possible"""
          self.stop_flag.set()
          self.logger.debug("Stop flag set in ManagerGroup")
  
      def test_count(self):
          return sum(manager.test_count for manager in self.pool)
  
      def unexpected_count(self):
          return sum(manager.unexpected_count for manager in self.pool)
  