Correct imap sensor measurement class and add suggested precision (#94060)

* Fix imap sensor measurement class and precision

* Test measurement class is set correctly

* Remove unrelated changes

* Move EntityDescription to module level

homeassistant/components/imap/sensor.py

@@ -1,7 +1,11 @@
 """IMAP sensor support."""
 from __future__ import annotations
 
-from homeassistant.components.sensor import SensorEntity
+from homeassistant.components.sensor import (
+    SensorEntity,
+    SensorEntityDescription,
+    SensorStateClass,
+)
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import CONF_USERNAME
 from homeassistant.core import HomeAssistant
@@ -13,6 +17,12 @@ from homeassistant.helpers.update_coordinator import CoordinatorEntity
 from . import ImapPollingDataUpdateCoordinator, ImapPushDataUpdateCoordinator
 from .const import DOMAIN
 
+IMAP_MAIL_COUNT_DESCRIPTION = SensorEntityDescription(
+    key="imap_mail_count",
+    state_class=SensorStateClass.MEASUREMENT,
+    suggested_display_precision=0,
+)
+
 
 async def async_setup_entry(
     hass: HomeAssistant, entry: ConfigEntry, async_add_entities: AddEntitiesCallback
@@ -22,8 +32,7 @@ async def async_setup_entry(
     coordinator: ImapPushDataUpdateCoordinator | ImapPollingDataUpdateCoordinator = (
         hass.data[DOMAIN][entry.entry_id]
     )
-
-    async_add_entities([ImapSensor(coordinator)])
+    async_add_entities([ImapSensor(coordinator, IMAP_MAIL_COUNT_DESCRIPTION)])
 
 
 class ImapSensor(
@@ -38,9 +47,11 @@ class ImapSensor(
     def __init__(
         self,
         coordinator: ImapPushDataUpdateCoordinator | ImapPollingDataUpdateCoordinator,
+        description: SensorEntityDescription,
     ) -> None:
         """Initialize the sensor."""
         super().__init__(coordinator)
+        self.entity_description = description
         self._attr_unique_id = f"{coordinator.config_entry.entry_id}"
         self._attr_device_info = DeviceInfo(
             identifiers={(DOMAIN, coordinator.config_entry.entry_id)},

tests/components/imap/test_init.py

@@ -9,6 +9,7 @@ import pytest
 
 from homeassistant.components.imap import DOMAIN
 from homeassistant.components.imap.errors import InvalidAuth, InvalidFolder
+from homeassistant.components.sensor.const import SensorStateClass
 from homeassistant.const import STATE_UNAVAILABLE
 from homeassistant.core import HomeAssistant
 from homeassistant.util.dt import utcnow
@@ -135,6 +136,7 @@ async def test_receiving_message_successfully(
     # we should have received one message
     assert state is not None
     assert state.state == "1"
+    assert state.attributes["state_class"] == SensorStateClass.MEASUREMENT
 
     # we should have received one event
     assert len(event_called) == 1