From 347ef9cb4c7ed6c540944dc5f2f34898239a713d Mon Sep 17 00:00:00 2001
From: Franck Nijhof <git@frenck.dev>
Date: Mon, 14 Jun 2021 18:05:01 +0200
Subject: [PATCH] Define NumberEntity entity attributes as class variables
 (#51842)

---
 homeassistant/components/demo/number.py     | 87 ++++++---------------
 homeassistant/components/number/__init__.py | 18 +++--
 2 files changed, 38 insertions(+), 67 deletions(-)

diff --git a/homeassistant/components/demo/number.py b/homeassistant/components/demo/number.py
index f3fd815f621..a6842d2ca43 100644
--- a/homeassistant/components/demo/number.py
+++ b/homeassistant/components/demo/number.py
@@ -1,4 +1,6 @@
 """Demo platform that offers a fake Number entity."""
+from __future__ import annotations
+
 import voluptuous as vol
 
 from homeassistant.components.number import NumberEntity
@@ -40,26 +42,32 @@ async def async_setup_entry(hass, config_entry, async_add_entities):
 class DemoNumber(NumberEntity):
     """Representation of a demo Number entity."""
 
+    _attr_should_poll = False
+
     def __init__(
         self,
-        unique_id,
-        name,
-        state,
-        icon,
-        assumed,
-        min_value=None,
-        max_value=None,
+        unique_id: str,
+        name: str,
+        state: float,
+        icon: str,
+        assumed: bool,
+        min_value: float | None = None,
+        max_value: float | None = None,
         step=None,
-    ):
+    ) -> None:
         """Initialize the Demo Number entity."""
-        self._unique_id = unique_id
-        self._name = name or DEVICE_DEFAULT_NAME
-        self._state = state
-        self._icon = icon
-        self._assumed = assumed
-        self._min_value = min_value
-        self._max_value = max_value
-        self._step = step
+        self._attr_assumed_state = assumed
+        self._attr_icon = icon
+        self._attr_name = name or DEVICE_DEFAULT_NAME
+        self._attr_unique_id = unique_id
+        self._attr_value = state
+
+        if min_value is not None:
+            self._attr_min_value = min_value
+        if max_value is not None:
+            self._attr_max_value = max_value
+        if step is not None:
+            self._attr_step = step
 
     @property
     def device_info(self):
@@ -72,51 +80,6 @@ class DemoNumber(NumberEntity):
             "name": self.name,
         }
 
-    @property
-    def unique_id(self):
-        """Return the unique id."""
-        return self._unique_id
-
-    @property
-    def should_poll(self):
-        """No polling needed for a demo Number entity."""
-        return False
-
-    @property
-    def name(self):
-        """Return the name of the device if any."""
-        return self._name
-
-    @property
-    def icon(self):
-        """Return the icon to use for device if any."""
-        return self._icon
-
-    @property
-    def assumed_state(self):
-        """Return if the state is based on assumptions."""
-        return self._assumed
-
-    @property
-    def value(self):
-        """Return the current value."""
-        return self._state
-
-    @property
-    def min_value(self):
-        """Return the minimum value."""
-        return self._min_value or super().min_value
-
-    @property
-    def max_value(self):
-        """Return the maximum value."""
-        return self._max_value or super().max_value
-
-    @property
-    def step(self):
-        """Return the value step."""
-        return self._step or super().step
-
     async def async_set_value(self, value):
         """Update the current value."""
         num_value = float(value)
@@ -126,5 +89,5 @@ class DemoNumber(NumberEntity):
                 f"Invalid value for {self.entity_id}: {value} (range {self.min_value} - {self.max_value})"
             )
 
-        self._state = num_value
+        self._attr_value = num_value
         self.async_write_ha_state()
diff --git a/homeassistant/components/number/__init__.py b/homeassistant/components/number/__init__.py
index 046895ac29c..897186dce7b 100644
--- a/homeassistant/components/number/__init__.py
+++ b/homeassistant/components/number/__init__.py
@@ -1,10 +1,9 @@
 """Component to allow numeric input for platforms."""
 from __future__ import annotations
 
-from abc import abstractmethod
 from datetime import timedelta
 import logging
-from typing import Any
+from typing import Any, final
 
 import voluptuous as vol
 
@@ -68,6 +67,12 @@ async def async_unload_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
 class NumberEntity(Entity):
     """Representation of a Number entity."""
 
+    _attr_max_value: float = DEFAULT_MAX_VALUE
+    _attr_min_value: float = DEFAULT_MIN_VALUE
+    _attr_state: None = None
+    _attr_step: float
+    _attr_value: float
+
     @property
     def capability_attributes(self) -> dict[str, Any]:
         """Return capability attributes."""
@@ -80,16 +85,18 @@ class NumberEntity(Entity):
     @property
     def min_value(self) -> float:
         """Return the minimum value."""
-        return DEFAULT_MIN_VALUE
+        return self._attr_min_value
 
     @property
     def max_value(self) -> float:
         """Return the maximum value."""
-        return DEFAULT_MAX_VALUE
+        return self._attr_max_value
 
     @property
     def step(self) -> float:
         """Return the increment/decrement step."""
+        if hasattr(self, "_attr_step"):
+            return self._attr_step
         step = DEFAULT_STEP
         value_range = abs(self.max_value - self.min_value)
         if value_range != 0:
@@ -98,14 +105,15 @@ class NumberEntity(Entity):
         return step
 
     @property
+    @final
     def state(self) -> float:
         """Return the entity state."""
         return self.value
 
     @property
-    @abstractmethod
     def value(self) -> float:
         """Return the entity value to represent the entity state."""
+        return self._attr_value
 
     def set_value(self, value: float) -> None:
         """Set new value."""