Add strict typing to Whois (#62959)

.strict-typing

@@ -158,6 +158,7 @@ homeassistant.components.watttime.*
 homeassistant.components.weather.*
 homeassistant.components.websocket_api.*
 homeassistant.components.wemo.*
+homeassistant.components.whois.*
 homeassistant.components.zodiac.*
 homeassistant.components.zeroconf.*
 homeassistant.components.zone.*

homeassistant/components/whois/sensor.py

@@ -1,4 +1,6 @@
 """Get WHOIS information for a given host."""
+from __future__ import annotations
+
 from datetime import timedelta
 import logging
 
@@ -7,7 +9,10 @@ import whois
 
 from homeassistant.components.sensor import PLATFORM_SCHEMA, SensorEntity
 from homeassistant.const import CONF_DOMAIN, CONF_NAME, TIME_DAYS
+from homeassistant.core import HomeAssistant
 import homeassistant.helpers.config_validation as cv
+from homeassistant.helpers.entity_platform import AddEntitiesCallback
+from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -28,10 +33,15 @@ PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
 )
 
 
-def setup_platform(hass, config, add_entities, discovery_info=None):
+def setup_platform(
+    hass: HomeAssistant,
+    config: ConfigType,
+    add_entities: AddEntitiesCallback,
+    discovery_info: DiscoveryInfoType | None = None,
+) -> None:
     """Set up the WHOIS sensor."""
-    domain = config.get(CONF_DOMAIN)
-    name = config.get(CONF_NAME)
+    domain = config[CONF_DOMAIN]
+    name = config[CONF_NAME]
 
     try:
         if "expiration_date" in whois.whois(domain):
@@ -52,18 +62,18 @@ class WhoisSensor(SensorEntity):
     _attr_icon = "mdi:calendar-clock"
     _attr_native_unit_of_measurement = TIME_DAYS
 
-    def __init__(self, name, domain):
+    def __init__(self, name: str, domain: str) -> None:
         """Initialize the sensor."""
         self.whois = whois.whois
         self._domain = domain
         self._attr_name = name
 
-    def _empty_value_and_attributes(self):
+    def _empty_value_and_attributes(self) -> None:
         """Empty the state and attributes on an error."""
         self._attr_native_value = None
-        self._attr_extra_state_attributes = None
+        self._attr_extra_state_attributes = {}
 
-    def update(self):
+    def update(self) -> None:
         """Get the current WHOIS data for the domain."""
         try:
             response = self.whois(self._domain)

mypy.ini

@@ -1749,6 +1749,17 @@ no_implicit_optional = true
 warn_return_any = true
 warn_unreachable = true
 
+[mypy-homeassistant.components.whois.*]
+check_untyped_defs = true
+disallow_incomplete_defs = true
+disallow_subclassing_any = true
+disallow_untyped_calls = true
+disallow_untyped_decorators = true
+disallow_untyped_defs = true
+no_implicit_optional = true
+warn_return_any = true
+warn_unreachable = true
+
 [mypy-homeassistant.components.zodiac.*]
 check_untyped_defs = true
 disallow_incomplete_defs = true