Use dynamic ports for test instances (#6232)

tests/common.py

@@ -10,6 +10,7 @@ import threading
 from contextlib import contextmanager
 
 from aiohttp import web
+from aiohttp.test_utils import unused_port as get_test_instance_port  # noqa
 
 from homeassistant import core as ha, loader
 from homeassistant.bootstrap import setup_component, DATA_SETUP
@@ -23,7 +24,7 @@ import homeassistant.util.yaml as yaml
 from homeassistant.const import (
     STATE_ON, STATE_OFF, DEVICE_DEFAULT_NAME, EVENT_TIME_CHANGED,
     EVENT_STATE_CHANGED, EVENT_PLATFORM_DISCOVERED, ATTR_SERVICE,
-    ATTR_DISCOVERED, SERVER_PORT, EVENT_HOMEASSISTANT_STOP)
+    ATTR_DISCOVERED, EVENT_HOMEASSISTANT_STOP)
 from homeassistant.components import sun, mqtt, recorder
 from homeassistant.components.http.auth import auth_middleware
 from homeassistant.components.http.const import (
@@ -31,7 +32,6 @@ from homeassistant.components.http.const import (
 from homeassistant.util.async import (
     run_callback_threadsafe, run_coroutine_threadsafe)
 
-_TEST_INSTANCE_PORT = SERVER_PORT
 _LOGGER = logging.getLogger(__name__)
 INST_COUNT = 0
 
@@ -139,18 +139,6 @@ def async_test_home_assistant(loop):
     return hass
 
 
-def get_test_instance_port():
-    """Return unused port for running test instance.
-
-    The socket that holds the default port does not get released when we stop
-    HA in a different test case. Until I have figured out what is going on,
-    let's run each test on a different port.
-    """
-    global _TEST_INSTANCE_PORT
-    _TEST_INSTANCE_PORT += 1
-    return _TEST_INSTANCE_PORT
-
-
 def mock_service(hass, domain, service):
     """Setup a fake service.