Update test case

tests/components/mqtt/test_discovery.py

@@ -1,12 +1,15 @@
 """The tests for the MQTT discovery."""
 import asyncio
+import unittest
 from unittest.mock import patch
 
 from homeassistant.components.mqtt.discovery import async_start, \
                                                     ALREADY_DISCOVERED
+from homeassistant.const import STATE_ON, STATE_OFF
 
-from tests.common import async_fire_mqtt_message, mock_coro
-
+from tests.common import (
+    mock_mqtt_component, fire_mqtt_message, get_test_home_assistant,
+    async_fire_mqtt_message, mock_coro)
 
 @asyncio.coroutine
 def test_subscribing_config_topic(hass, mqtt_mock):
@@ -189,17 +192,25 @@ def test_discovery_expansion(hass, mqtt_mock, caplog):
     yield from async_start(hass, 'homeassistant', {})
 
     data = (
-        '{ "name": "DiscoveryExpansionTest",'
-        '  "stat_t": "test_topic",'
-        '  "cmd_t": "test_topic" }'
+        '{ "~": "some/prefix",'
+        '  "name": "DiscoveryExpansionTest",'
+        '  "stat_t": "~/test_topic",'
+        '  "cmd_t": "~/test_topic" }'
     )
 
     async_fire_mqtt_message(
         hass, 'homeassistant/switch/bla/config', data)
     yield from hass.async_block_till_done()
 
     state = hass.states.get('switch.DiscoveryExpansionTest')
-
     assert state is not None
     assert state.name == 'DiscoveryExpansionTest'
     assert ('switch', 'bla') in hass.data[ALREADY_DISCOVERED]
+    assert state.state == STATE_OFF
+
+    async_fire_mqtt_message(hass, 'some/prefix/test_topic', 'ON')
+    yield from hass.async_block_till_done()
+    yield from hass.async_block_till_done()
+
+    state = hass.states.get('switch.DiscoveryExpansionTest')
+    assert state.state == STATE_ON