Add tests for mFi sensors

Note that some of the indirection here is so that I can reuse
a few things for mFi switch tests to follow.

.coveragerc

@@ -122,7 +122,6 @@ omit =
     homeassistant/components/sensor/eliqonline.py
     homeassistant/components/sensor/forecast.py
     homeassistant/components/sensor/glances.py
-    homeassistant/components/sensor/mfi.py
     homeassistant/components/sensor/netatmo.py
     homeassistant/components/sensor/onewire.py
     homeassistant/components/sensor/openweathermap.py

tests/components/sensor/test_mfi.py

@@ -0,0 +1,138 @@
+"""
+tests.components.sensor.test_mfi
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Tests mFi sensor.
+"""
+import unittest
+import unittest.mock as mock
+
+import homeassistant.core as ha
+import homeassistant.components.sensor as sensor
+import homeassistant.components.sensor.mfi as mfi
+from homeassistant.const import TEMP_CELCIUS
+
+
+class TestMfiSensorSetup(unittest.TestCase):
+    PLATFORM = mfi
+    COMPONENT = sensor
+    THING = 'sensor'
+    GOOD_CONFIG = {
+        'sensor': {
+            'platform': 'mfi',
+            'host': 'foo',
+            'port': 6123,
+            'username': 'user',
+            'password': 'pass',
+        }
+    }
+
+    def setup_method(self, method):
+        self.hass = ha.HomeAssistant()
+        self.hass.config.latitude = 32.87336
+        self.hass.config.longitude = 117.22743
+
+    def teardown_method(self, method):
+        """ Stop down stuff we started. """
+        self.hass.stop()
+
+    def test_setup_missing_config(self):
+        config = {
+            'sensor': {
+                'platform': 'mfi',
+            }
+        }
+        self.assertFalse(self.PLATFORM.setup_platform(self.hass, config, None))
+
+    @mock.patch('mficlient.client')
+    def test_setup_failed_login(self, mock_client):
+        mock_client.FailedToLogin = Exception()
+        mock_client.MFiClient.side_effect = mock_client.FailedToLogin
+        self.assertFalse(
+            self.PLATFORM.setup_platform(self.hass,
+                                         dict(self.GOOD_CONFIG),
+                                         None))
+
+    @mock.patch('mficlient.client.MFiClient')
+    def test_setup_minimum(self, mock_client):
+        config = dict(self.GOOD_CONFIG)
+        del config[self.THING]['port']
+        assert self.COMPONENT.setup(self.hass, config)
+        mock_client.assert_called_once_with('foo', 'user', 'pass',
+                                            port=6443)
+
+    @mock.patch('mficlient.client.MFiClient')
+    def test_setup_with_port(self, mock_client):
+        config = dict(self.GOOD_CONFIG)
+        config[self.THING]['port'] = 6123
+        assert self.COMPONENT.setup(self.hass, config)
+        mock_client.assert_called_once_with('foo', 'user', 'pass',
+                                            port=6123)
+
+    @mock.patch('mficlient.client.MFiClient')
+    @mock.patch('homeassistant.components.sensor.mfi.MfiSensor')
+    def test_setup_adds_proper_devices(self, mock_sensor, mock_client):
+        ports = {i: mock.MagicMock(model=model)
+                 for i, model in enumerate(mfi.SENSOR_MODELS)}
+        ports['bad'] = mock.MagicMock(model='notasensor')
+        print(ports['bad'].model)
+        mock_client.return_value.get_devices.return_value = \
+            [mock.MagicMock(ports=ports)]
+        assert sensor.setup(self.hass, self.GOOD_CONFIG)
+        for ident, port in ports.items():
+            if ident != 'bad':
+                mock_sensor.assert_any_call(port, self.hass)
+        assert mock.call(ports['bad'], self.hass) not in mock_sensor.mock_calls
+
+
+class TestMfiSensor(unittest.TestCase):
+    def setup_method(self, method):
+        self.hass = ha.HomeAssistant()
+        self.hass.config.latitude = 32.87336
+        self.hass.config.longitude = 117.22743
+        self.port = mock.MagicMock()
+        self.sensor = mfi.MfiSensor(self.port, self.hass)
+
+    def teardown_method(self, method):
+        """ Stop down stuff we started. """
+        self.hass.stop()
+
+    def test_name(self):
+        self.assertEqual(self.port.label, self.sensor.name)
+
+    def test_uom_temp(self):
+        self.port.tag = 'temperature'
+        self.assertEqual(TEMP_CELCIUS, self.sensor.unit_of_measurement)
+
+    def test_uom_power(self):
+        self.port.tag = 'active_pwr'
+        self.assertEqual('Watts', self.sensor.unit_of_measurement)
+
+    def test_uom_digital(self):
+        self.port.model = 'Input Digital'
+        self.assertEqual('State', self.sensor.unit_of_measurement)
+
+    def test_uom_unknown(self):
+        self.port.tag = 'balloons'
+        self.assertEqual('balloons', self.sensor.unit_of_measurement)
+
+    def test_state_digital(self):
+        self.port.model = 'Input Digital'
+        self.port.value = 0
+        self.assertEqual(mfi.STATE_OFF, self.sensor.state)
+        self.port.value = 1
+        self.assertEqual(mfi.STATE_ON, self.sensor.state)
+        self.port.value = 2
+        self.assertEqual(mfi.STATE_ON, self.sensor.state)
+
+    def test_state_digits(self):
+        self.port.tag = 'didyoucheckthedict?'
+        self.port.value = 1.25
+        with mock.patch.dict(mfi.DIGITS, {'didyoucheckthedict?': 1}):
+            self.assertEqual(1.2, self.sensor.state)
+        with mock.patch.dict(mfi.DIGITS, {}):
+            self.assertEqual(1.0, self.sensor.state)
+
+    def test_update(self):
+        self.sensor.update()
+        self.port.refresh.assert_called_once_with()