text: """Test the helper method for writing tests."""
  import asyncio
  from datetime import timedelta
  import functools as ft
  import os
  import sys
  from unittest.mock import patch, MagicMock, Mock
  from io import StringIO
  import logging
  import threading
  from contextlib import contextmanager
  
  from homeassistant import auth, core as ha, data_entry_flow, config_entries
  from homeassistant.setup import setup_component, async_setup_component
  from homeassistant.config import async_process_component_config
  from homeassistant.helpers import (
      intent, entity, restore_state, entity_registry,
      entity_platform)
  from homeassistant.util.unit_system import METRIC_SYSTEM
  import homeassistant.util.dt as date_util
  import homeassistant.util.yaml as yaml
  from homeassistant.const import (
      STATE_ON, STATE_OFF, DEVICE_DEFAULT_NAME, EVENT_TIME_CHANGED,
      EVENT_STATE_CHANGED, EVENT_PLATFORM_DISCOVERED, ATTR_SERVICE,
      ATTR_DISCOVERED, SERVER_PORT, EVENT_HOMEASSISTANT_CLOSE)
  from homeassistant.components import mqtt, recorder
  from homeassistant.util.async_ import (
      run_callback_threadsafe, run_coroutine_threadsafe)
  
  _TEST_INSTANCE_PORT = SERVER_PORT
  _LOGGER = logging.getLogger(__name__)
  INSTANCES = []
  
  
  def threadsafe_callback_factory(func):
      """Create threadsafe functions out of callbacks.
  
      Callback needs to have `hass` as first argument.
      """
      @ft.wraps(func)
      def threadsafe(*args, **kwargs):
          """Call func threadsafe."""
          hass = args[0]
          return run_callback_threadsafe(
              hass.loop, ft.partial(func, *args, **kwargs)).result()
  
      return threadsafe
  
  
  def threadsafe_coroutine_factory(func):
      """Create threadsafe functions out of coroutine.
  
      Callback needs to have `hass` as first argument.
      """
      @ft.wraps(func)
      def threadsafe(*args, **kwargs):
          """Call func threadsafe."""
          hass = args[0]
          return run_coroutine_threadsafe(
              func(*args, **kwargs), hass.loop).result()
  
      return threadsafe
  
  
  def get_test_config_dir(*add_path):
      """Return a path to a test config dir."""
      return os.path.join(os.path.dirname(__file__), 'testing_config', *add_path)
  
  
  def get_test_home_assistant():
      """Return a Home Assistant object pointing at test config directory."""
      if sys.platform == "win32":
          loop = asyncio.ProactorEventLoop()
      else:
          loop = asyncio.new_event_loop()
  
      hass = loop.run_until_complete(async_test_home_assistant(loop))
  
      stop_event = threading.Event()
  
      def run_loop():
          """Run event loop."""
          # pylint: disable=protected-access
          loop._thread_ident = threading.get_ident()
          loop.run_forever()
          stop_event.set()
  
      orig_stop = hass.stop
  
      def start_hass(*mocks):
          """Start hass."""
          run_coroutine_threadsafe(hass.async_start(), loop=hass.loop).result()
  
      def stop_hass():
          """Stop hass."""
          orig_stop()
          stop_event.wait()
          loop.close()
  
      hass.start = start_hass
      hass.stop = stop_hass
  
      threading.Thread(name="LoopThread", target=run_loop, daemon=False).start()
  
      return hass
  
  
  # pylint: disable=protected-access
  @asyncio.coroutine
  def async_test_home_assistant(loop):
      """Return a Home Assistant object pointing at test config dir."""
      hass = ha.HomeAssistant(loop)
      hass.config.async_load = Mock()
      store = auth.AuthStore(hass)
      hass.auth = auth.AuthManager(hass, store, {})
      ensure_auth_manager_loaded(hass.auth)
      INSTANCES.append(hass)
  
      orig_async_add_job = hass.async_add_job
  
      def async_add_job(target, *args):
          """Add a magic mock."""
          if isinstance(target, Mock):
              return mock_coro(target(*args))
          return orig_async_add_job(target, *args)
  
      hass.async_add_job = async_add_job
  
      hass.config.location_name = 'test home'
      hass.config.config_dir = get_test_config_dir()
      hass.config.latitude = 32.87336
      hass.config.longitude = -117.22743
      hass.config.elevation = 0
      hass.config.time_zone = date_util.get_time_zone('US/Pacific')
      hass.config.units = METRIC_SYSTEM
      hass.config.skip_pip = True
  
      hass.config_entries = config_entries.ConfigEntries(hass, {})
      hass.config_entries._entries = []
      hass.config_entries._store._async_ensure_stop_listener = lambda: None
  
      hass.state = ha.CoreState.running
  
      # Mock async_start
      orig_start = hass.async_start
  
      @asyncio.coroutine
      def mock_async_start():
          """Start the mocking."""
          # We only mock time during tests and we want to track tasks
          with patch('homeassistant.core._async_create_timer'), \
                  patch.object(hass, 'async_stop_track_tasks'):
              yield from orig_start()
  
      hass.async_start = mock_async_start
  
      @ha.callback
      def clear_instance(event):
          """Clear global instance."""
          INSTANCES.remove(hass)
  
      hass.bus.async_listen_once(EVENT_HOMEASSISTANT_CLOSE, clear_instance)
  
      return hass
  
  
  def get_test_instance_port():
      """Return unused port for running test instance.
  
      The socket that holds the default port does not get released when we stop
      HA in a different test case. Until I have figured out what is going on,
      let's run each test on a different port.
      """
      global _TEST_INSTANCE_PORT
      _TEST_INSTANCE_PORT += 1
      return _TEST_INSTANCE_PORT
  
  
  @ha.callback
  def async_mock_service(hass, domain, service, schema=None):
      """Set up a fake service & return a calls log list to this service."""
      calls = []
  
      @asyncio.coroutine
      def mock_service_log(call):  # pylint: disable=unnecessary-lambda
          """Mock service call."""
          calls.append(call)
  
      hass.services.async_register(
          domain, service, mock_service_log, schema=schema)
  
      return calls
  
  
  mock_service = threadsafe_callback_factory(async_mock_service)
  
  
  @ha.callback
  def async_mock_intent(hass, intent_typ):
      """Set up a fake intent handler."""
      intents = []
  
      class MockIntentHandler(intent.IntentHandler):
          intent_type = intent_typ
  
          @asyncio.coroutine
          def async_handle(self, intent):
              """Handle the intent."""
              intents.append(intent)
              return intent.create_response()
  
      intent.async_register(hass, MockIntentHandler())
  
      return intents
  
  
  @ha.callback
  def async_fire_mqtt_message(hass, topic, payload, qos=0, retain=False):
      """Fire the MQTT message."""
      if isinstance(payload, str):
          payload = payload.encode('utf-8')
      msg = mqtt.Message(topic, payload, qos, retain)
      hass.async_run_job(hass.data['mqtt']._mqtt_on_message, None, None, msg)
  
  
  fire_mqtt_message = threadsafe_callback_factory(async_fire_mqtt_message)
  
  
  @ha.callback
  def async_fire_time_changed(hass, time):
      """Fire a time changes event."""
      hass.bus.async_fire(EVENT_TIME_CHANGED, {'now': time})
  
  
  fire_time_changed = threadsafe_callback_factory(async_fire_time_changed)
  
  
  def fire_service_discovered(hass, service, info):
      """Fire the MQTT message."""
      hass.bus.fire(EVENT_PLATFORM_DISCOVERED, {
          ATTR_SERVICE: service,
          ATTR_DISCOVERED: info
      })
  
  
  def load_fixture(filename):
      """Load a fixture."""
      path = os.path.join(os.path.dirname(__file__), 'fixtures', filename)
      with open(path, encoding='utf-8') as fptr:
          return fptr.read()
  
  
  def mock_state_change_event(hass, new_state, old_state=None):
      """Mock state change envent."""
      event_data = {
          'entity_id': new_state.entity_id,
          'new_state': new_state,
      }
  
      if old_state:
          event_data['old_state'] = old_state
  
      hass.bus.fire(EVENT_STATE_CHANGED, event_data)
  
  
  @asyncio.coroutine
  def async_mock_mqtt_component(hass, config=None):
      """Mock the MQTT component."""
      if config is None:
          config = {mqtt.CONF_BROKER: 'mock-broker'}
  
      with patch('paho.mqtt.client.Client') as mock_client:
          mock_client().connect.return_value = 0
          mock_client().subscribe.return_value = (0, 0)
          mock_client().publish.return_value = (0, 0)
  
          result = yield from async_setup_component(hass, mqtt.DOMAIN, {
              mqtt.DOMAIN: config
          })
          assert result
  
          hass.data['mqtt'] = MagicMock(spec_set=hass.data['mqtt'],
                                        wraps=hass.data['mqtt'])
  
          return hass.data['mqtt']
  
  
  mock_mqtt_component = threadsafe_coroutine_factory(async_mock_mqtt_component)
  
  
  @ha.callback
  def mock_component(hass, component):
      """Mock a component is setup."""
      if component in hass.config.components:
          AssertionError("Component {} is already setup".format(component))
  
      hass.config.components.add(component)
  
  
  def mock_registry(hass, mock_entries=None):
      """Mock the Entity Registry."""
      registry = entity_registry.EntityRegistry(hass)
      registry.entities = mock_entries or {}
      hass.data[entity_registry.DATA_REGISTRY] = registry
      return registry
  
  
  class MockUser(auth.User):
      """Mock a user in Home Assistant."""
  
      def __init__(self, id='mock-id', is_owner=True, is_active=True,
                   name='Mock User'):
          """Initialize mock user."""
          super().__init__(id, is_owner, is_active, name)
  
      def add_to_hass(self, hass):
          """Test helper to add entry to hass."""
          return self.add_to_auth_manager(hass.auth)
  
      def add_to_auth_manager(self, auth_mgr):
          """Test helper to add entry to hass."""
          auth_mgr._store.users[self.id] = self
          return self
  
  
  @ha.callback
  def ensure_auth_manager_loaded(auth_mgr):
      """Ensure an auth manager is considered loaded."""
      store = auth_mgr._store
      if store.clients is None:
          store.clients = {}
      if store.users is None:
          store.users = {}
  
  
  class MockModule(object):
      """Representation of a fake module."""
  
      # pylint: disable=invalid-name
      def __init__(self, domain=None, dependencies=None, setup=None,
                   requirements=None, config_schema=None, platform_schema=None,
                   async_setup=None, async_setup_entry=None,
                   async_unload_entry=None):
          """Initialize the mock module."""
          self.DOMAIN = domain
          self.DEPENDENCIES = dependencies or []
          self.REQUIREMENTS = requirements or []
  
          if config_schema is not None:
              self.CONFIG_SCHEMA = config_schema
  
          if platform_schema is not None:
              self.PLATFORM_SCHEMA = platform_schema
  
          if setup is not None:
              # We run this in executor, wrap it in function
              self.setup = lambda *args: setup(*args)
  
          if async_setup is not None:
              self.async_setup = async_setup
  
          if setup is None and async_setup is None:
              self.async_setup = mock_coro_func(True)
  
          if async_setup_entry is not None:
              self.async_setup_entry = async_setup_entry
  
          if async_unload_entry is not None:
              self.async_unload_entry = async_unload_entry
  
  
  class MockPlatform(object):
      """Provide a fake platform."""
  
      # pylint: disable=invalid-name
      def __init__(self, setup_platform=None, dependencies=None,
                   platform_schema=None, async_setup_platform=None,
                   async_setup_entry=None, scan_interval=None):
          """Initialize the platform."""
          self.DEPENDENCIES = dependencies or []
  
          if platform_schema is not None:
              self.PLATFORM_SCHEMA = platform_schema
  
          if scan_interval is not None:
              self.SCAN_INTERVAL = scan_interval
  
          if setup_platform is not None:
              # We run this in executor, wrap it in function
              self.setup_platform = lambda *args: setup_platform(*args)
  
          if async_setup_platform is not None:
              self.async_setup_platform = async_setup_platform
  
          if async_setup_entry is not None:
              self.async_setup_entry = async_setup_entry
  
          if setup_platform is None and async_setup_platform is None:
              self.async_setup_platform = mock_coro_func()
  
  
  class MockEntityPlatform(entity_platform.EntityPlatform):
      """Mock class with some mock defaults."""
  
      def __init__(
          self, hass,
          logger=None,
          domain='test_domain',
          platform_name='test_platform',
          platform=None,
          scan_interval=timedelta(seconds=15),
          entity_namespace=None,
          async_entities_added_callback=lambda: None
      ):
          """Initialize a mock entity platform."""
          if logger is None:
              logger = logging.getLogger('homeassistant.helpers.entity_platform')
  
          # Otherwise the constructor will blow up.
          if (isinstance(platform, Mock) and
                  isinstance(platform.PARALLEL_UPDATES, Mock)):
              platform.PARALLEL_UPDATES = 0
  
          super().__init__(
              hass=hass,
              logger=logger,
              domain=domain,
              platform_name=platform_name,
              platform=platform,
              scan_interval=scan_interval,
              entity_namespace=entity_namespace,
              async_entities_added_callback=async_entities_added_callback,
          )
  
  
  class MockToggleDevice(entity.ToggleEntity):
      """Provide a mock toggle device."""
  
      def __init__(self, name, state):
          """Initialize the mock device."""
          self._name = name or DEVICE_DEFAULT_NAME
          self._state = state
          self.calls = []
  
      @property
      def name(self):
          """Return the name of the device if any."""
          self.calls.append(('name', {}))
          return self._name
  
      @property
      def state(self):
          """Return the name of the device if any."""
          self.calls.append(('state', {}))
          return self._state
  
      @property
      def is_on(self):
          """Return true if device is on."""
          self.calls.append(('is_on', {}))
          return self._state == STATE_ON
  
      def turn_on(self, **kwargs):
          """Turn the device on."""
          self.calls.append(('turn_on', kwargs))
          self._state = STATE_ON
  
      def turn_off(self, **kwargs):
          """Turn the device off."""
          self.calls.append(('turn_off', kwargs))
          self._state = STATE_OFF
  
      def last_call(self, method=None):
          """Return the last call."""
          if not self.calls:
              return None
          elif method is None:
              return self.calls[-1]
          else:
              try:
                  return next(call for call in reversed(self.calls)
                              if call[0] == method)
              except StopIteration:
                  return None
  
  
  class MockConfigEntry(config_entries.ConfigEntry):
      """Helper for creating config entries that adds some defaults."""
  
      def __init__(self, *, domain='test', data=None, version=0, entry_id=None,
                   source=data_entry_flow.SOURCE_USER, title='Mock Title',
                   state=None):
          """Initialize a mock config entry."""
          kwargs = {
              'entry_id': entry_id or 'mock-id',
              'domain': domain,
              'data': data or {},
              'version': version,
              'title': title
          }
          if source is not None:
              kwargs['source'] = source
          if state is not None:
              kwargs['state'] = state
          super().__init__(**kwargs)
  
      def add_to_hass(self, hass):
          """Test helper to add entry to hass."""
          hass.config_entries._entries.append(self)
  
      def add_to_manager(self, manager):
          """Test helper to add entry to entry manager."""
          manager._entries.append(self)
  
  
  def patch_yaml_files(files_dict, endswith=True):
      """Patch load_yaml with a dictionary of yaml files."""
      # match using endswith, start search with longest string
      matchlist = sorted(list(files_dict.keys()), key=len) if endswith else []
  
      def mock_open_f(fname, **_):
          """Mock open() in the yaml module, used by load_yaml."""
          # Return the mocked file on full match
          if fname in files_dict:
              _LOGGER.debug("patch_yaml_files match %s", fname)
              res = StringIO(files_dict[fname])
              setattr(res, 'name', fname)
              return res
  
          # Match using endswith
          for ends in matchlist:
              if fname.endswith(ends):
                  _LOGGER.debug("patch_yaml_files end match %s: %s", ends, fname)
                  res = StringIO(files_dict[ends])
                  setattr(res, 'name', fname)
                  return res
  
          # Fallback for hass.components (i.e. services.yaml)
          if 'homeassistant/components' in fname:
              _LOGGER.debug("patch_yaml_files using real file: %s", fname)
              return open(fname, encoding='utf-8')
  
          # Not found
          raise FileNotFoundError("File not found: {}".format(fname))
  
      return patch.object(yaml, 'open', mock_open_f, create=True)
  
  
  def mock_coro(return_value=None):
      """Return a coro that returns a value."""
      return mock_coro_func(return_value)()
  
  
  def mock_coro_func(return_value=None):
      """Return a method to create a coro function that returns a value."""
      @asyncio.coroutine
      def coro(*args, **kwargs):
          """Fake coroutine."""
          return return_value
  
      return coro
  
  
  @contextmanager
  def assert_setup_component(count, domain=None):
      """Collect valid configuration from setup_component.
  
      - count: The amount of valid platforms that should be setup
      - domain: The domain to count is optional. It can be automatically
                determined most of the time
  
      Use as a context manager around setup.setup_component
          with assert_setup_component(0) as result_config:
              setup_component(hass, domain, start_config)
              # using result_config is optional
      """
      config = {}
  
      @ha.callback
      def mock_psc(hass, config_input, domain):
          """Mock the prepare_setup_component to capture config."""
          res = async_process_component_config(
              hass, config_input, domain)
          config[domain] = None if res is None else res.get(domain)
          _LOGGER.debug("Configuration for %s, Validated: %s, Original %s",
                        domain, config[domain], config_input.get(domain))
          return res
  
      assert isinstance(config, dict)
      with patch('homeassistant.config.async_process_component_config',
                 mock_psc):
          yield config
  
      if domain is None:
          assert len(config) == 1, ('assert_setup_component requires DOMAIN: {}'
                                    .format(list(config.keys())))
          domain = list(config.keys())[0]
  
      res = config.get(domain)
      res_len = 0 if res is None else len(res)
      assert res_len == count, 'setup_component failed, expected {} got {}: {}' \
          .format(count, res_len, res)
  
  
  def init_recorder_component(hass, add_config=None):
      """Initialize the recorder."""
      config = dict(add_config) if add_config else {}
      config[recorder.CONF_DB_URL] = 'sqlite://'  # In memory DB
  
      with patch('homeassistant.components.recorder.migration.migrate_schema'):
          assert setup_component(hass, recorder.DOMAIN,
                                 {recorder.DOMAIN: config})
          assert recorder.DOMAIN in hass.config.components
      _LOGGER.info("In-memory recorder successfully started")
  
  
  def mock_restore_cache(hass, states):
      """Mock the DATA_RESTORE_CACHE."""
      key = restore_state.DATA_RESTORE_CACHE
      hass.data[key] = {
          state.entity_id: state for state in states}
      _LOGGER.debug('Restore cache: %s', hass.data[key])
      assert len(hass.data[key]) == len(states), \
          "Duplicate entity_id? {}".format(states)
      hass.state = ha.CoreState.starting
      mock_component(hass, recorder.DOMAIN)
  
  
  class MockDependency:
      """Decorator to mock install a dependency."""
  
      def __init__(self, root, *args):
          """Initialize decorator."""
          self.root = root
          self.submodules = args
  
      def __enter__(self):
          """Start mocking."""
          def resolve(mock, path):
              """Resolve a mock."""
              if not path:
                  return mock
  
              return resolve(getattr(mock, path[0]), path[1:])
  
          base = MagicMock()
          to_mock = {
              "{}.{}".format(self.root, tom): resolve(base, tom.split('.'))
              for tom in self.submodules
          }
          to_mock[self.root] = base
  
          self.patcher = patch.dict('sys.modules', to_mock)
          self.patcher.start()
          return base
  
      def __exit__(self, *exc):
          """Stop mocking."""
          self.patcher.stop()
          return False
  
      def __call__(self, func):
          """Apply decorator."""
          def run_mocked(*args, **kwargs):
              """Run with mocked dependencies."""
              with self as base:
                  args = list(args) + [base]
                  func(*args, **kwargs)
  
          return run_mocked
  
  
  class MockEntity(entity.Entity):
      """Mock Entity class."""
  
      def __init__(self, **values):
          """Initialize an entity."""
          self._values = values
  
          if 'entity_id' in values:
              self.entity_id = values['entity_id']
  
      @property
      def name(self):
          """Return the name of the entity."""
          return self._handle('name')
  
      @property
      def should_poll(self):
          """Return the ste of the polling."""
          return self._handle('should_poll')
  
      @property
      def unique_id(self):
          """Return the unique ID of the entity."""
          return self._handle('unique_id')
  
      @property
      def available(self):
          """Return True if entity is available."""
          return self._handle('available')
  
      def _handle(self, attr):
          """Helper for the attributes."""
          if attr in self._values:
              return self._values[attr]
          return getattr(super(), attr)
  