Fix Nissan Leaf default states (#59866)

* Fix default states and add device_class.

Car data is initialised to zero, which means that graphs have an ugly
drop to zero in them when HA is restarted. We should report "None" when
the state is unknown.

We need to use availability to signal whether binary_sensors have
sensible data or not.

We can remove the custom icons and use the defaults provided by using
appropriate device_class.

* Make isort happy.

* Explicitly return None

* Remove feature from bugfix PR.

homeassistant/components/nissan_leaf/__init__.py

@@ -213,12 +213,12 @@ class LeafDataStore:
         self.car_config = car_config
         self.force_miles = car_config[CONF_FORCE_MILES]
         self.data = {}
-        self.data[DATA_CLIMATE] = False
-        self.data[DATA_BATTERY] = 0
-        self.data[DATA_CHARGING] = False
-        self.data[DATA_RANGE_AC] = 0
-        self.data[DATA_RANGE_AC_OFF] = 0
-        self.data[DATA_PLUGGED_IN] = False
+        self.data[DATA_CLIMATE] = None
+        self.data[DATA_BATTERY] = None
+        self.data[DATA_CHARGING] = None
+        self.data[DATA_RANGE_AC] = None
+        self.data[DATA_RANGE_AC_OFF] = None
+        self.data[DATA_PLUGGED_IN] = None
         self.next_update = None
         self.last_check = None
         self.request_in_progress = False

homeassistant/components/nissan_leaf/binary_sensor.py

@@ -30,6 +30,11 @@ class LeafPluggedInSensor(LeafEntity, BinarySensorEntity):
         """Sensor name."""
         return f"{self.car.leaf.nickname} Plug Status"
 
+    @property
+    def available(self):
+        """Sensor availability."""
+        return self.car.data[DATA_PLUGGED_IN] is not None
+
     @property
     def is_on(self):
         """Return true if plugged in."""
@@ -51,6 +56,11 @@ class LeafChargingSensor(LeafEntity, BinarySensorEntity):
         """Sensor name."""
         return f"{self.car.leaf.nickname} Charging Status"
 
+    @property
+    def available(self):
+        """Sensor availability."""
+        return self.car.data[DATA_CHARGING] is not None
+
     @property
     def is_on(self):
         """Return true if charging."""

homeassistant/components/nissan_leaf/sensor.py

@@ -52,6 +52,8 @@ class LeafBatterySensor(LeafEntity, SensorEntity):
     @property
     def native_value(self):
         """Battery state percentage."""
+        if self.car.data[DATA_BATTERY] is None:
+            return None
         return round(self.car.data[DATA_BATTERY])
 
     @property
@@ -96,6 +98,9 @@ class LeafRangeSensor(LeafEntity, SensorEntity):
         else:
             ret = self.car.data[DATA_RANGE_AC_OFF]
 
+        if ret is None:
+            return None
+
         if not self.car.hass.config.units.is_metric or self.car.force_miles:
             ret = IMPERIAL_SYSTEM.length(ret, METRIC_SYSTEM.length_unit)