Do not reset current selection on reconfig or MQTT select (#85099)

* Do not reset current selection on reconfig

* Add a test

homeassistant/components/mqtt/select.py

@@ -113,6 +113,7 @@ class MqttSelect(MqttEntity, SelectEntity, RestoreEntity):
         discovery_data: DiscoveryInfoType | None,
     ) -> None:
         """Initialize the MQTT select."""
+        self._attr_current_option = None
         SelectEntity.__init__(self)
         MqttEntity.__init__(self, hass, config, config_entry, discovery_data)
 
@@ -123,7 +124,6 @@ class MqttSelect(MqttEntity, SelectEntity, RestoreEntity):
 
     def _setup_from_config(self, config: ConfigType) -> None:
         """(Re)Setup the entity."""
-        self._attr_current_option = None
         self._optimistic = config[CONF_OPTIMISTIC]
         self._attr_options = config[CONF_OPTIONS]
 

tests/components/mqtt/test_common.py

@@ -18,6 +18,7 @@ from homeassistant.const import (
     SERVICE_RELOAD,
     STATE_UNAVAILABLE,
 )
+from homeassistant.core import HomeAssistant
 from homeassistant.generated.mqtt import MQTT
 from homeassistant.helpers import device_registry as dr, entity_registry as er
 from homeassistant.helpers.dispatcher import async_dispatcher_send
@@ -1818,3 +1819,15 @@ async def help_test_unload_config_entry_with_platform(
 
     discovery_setup_entity = hass.states.get(f"{domain}.discovery_setup")
     assert discovery_setup_entity is None
+
+
+async def help_test_discovery_setup(
+    hass: HomeAssistant, domain: str, discovery_data_payload: str, name: str
+) -> None:
+    """Test setting up an MQTT entity using discovery."""
+    async_fire_mqtt_message(
+        hass, f"homeassistant/{domain}/{name}/config", discovery_data_payload
+    )
+    await hass.async_block_till_done()
+    state = hass.states.get(f"{domain}.{name}")
+    assert state.state is not None

tests/components/mqtt/test_select.py

@@ -29,6 +29,7 @@ from .test_common import (
     help_test_default_availability_payload,
     help_test_discovery_broken,
     help_test_discovery_removal,
+    help_test_discovery_setup,
     help_test_discovery_update,
     help_test_discovery_update_attr,
     help_test_discovery_update_unchanged,
@@ -455,7 +456,7 @@ async def test_discovery_update_select(hass, mqtt_mock_entry_no_yaml_config, cap
         "name": "Milk",
         "state_topic": "test-topic",
         "command_topic": "test-topic",
-        "options": ["milk", "beer"],
+        "options": ["milk"],
     }
 
     await help_test_discovery_update(
@@ -701,3 +702,27 @@ async def test_unload_entry(hass, mqtt_mock_entry_with_yaml_config, tmp_path):
     await help_test_unload_config_entry_with_platform(
         hass, mqtt_mock_entry_with_yaml_config, tmp_path, domain, config
     )
+
+
+async def test_persistent_state_after_reconfig(
+    hass: ha.HomeAssistant, mqtt_mock_entry_no_yaml_config
+) -> None:
+    """Test of the state is persistent after reconfiguring the select options."""
+    await mqtt_mock_entry_no_yaml_config()
+    discovery_data = '{ "name": "Milk", "state_topic": "test-topic", "command_topic": "test-topic", "options": ["milk", "beer"]}'
+    await help_test_discovery_setup(hass, SELECT_DOMAIN, discovery_data, "milk")
+
+    # assign an initial state
+    async_fire_mqtt_message(hass, "test-topic", "beer")
+    state = hass.states.get("select.milk")
+    assert state.state == "beer"
+    assert state.attributes["options"] == ["milk", "beer"]
+
+    # remove "milk" option
+    discovery_data = '{ "name": "Milk", "state_topic": "test-topic", "command_topic": "test-topic", "options": ["beer"]}'
+    await help_test_discovery_setup(hass, SELECT_DOMAIN, discovery_data, "milk")
+
+    # assert the state persistent
+    state = hass.states.get("select.milk")
+    assert state.state == "beer"
+    assert state.attributes["options"] == ["beer"]