Add type hints for MQTT common helper and fixtures (#87065)

tests/common.py

@@ -379,16 +379,34 @@ def async_mock_intent(hass, intent_typ):
 
 
 @callback
-def async_fire_mqtt_message(hass, topic, payload, qos=0, retain=False):
+def async_fire_mqtt_message(
+    hass: HomeAssistant,
+    topic: str,
+    payload: bytes | str,
+    qos: int = 0,
+    retain: bool = False,
+) -> None:
     """Fire the MQTT message."""
     # Local import to avoid processing MQTT modules when running a testcase
     # which does not use MQTT.
-    from homeassistant.components.mqtt.models import ReceiveMessage
+
+    # pylint: disable-next=import-outside-toplevel
+    from paho.mqtt.client import MQTTMessage
+
+    # pylint: disable-next=import-outside-toplevel
+    from homeassistant.components.mqtt.models import MqttData
 
     if isinstance(payload, str):
         payload = payload.encode("utf-8")
-    msg = ReceiveMessage(topic, payload, qos, retain)
-    hass.data["mqtt"].client._mqtt_handle_message(msg)
+
+    msg = MQTTMessage(topic=topic.encode("utf-8"))
+    msg.payload = payload
+    msg.qos = qos
+    msg.retain = retain
+
+    mqtt_data: MqttData = hass.data["mqtt"]
+    assert mqtt_data.client
+    mqtt_data.client._mqtt_handle_message(msg)
 
 
 fire_mqtt_message = threadsafe_callback_factory(async_fire_mqtt_message)