Fix test notifier

Author: Qizot

tests/support/asyncio_utils.py

@@ -16,9 +16,10 @@ async def _assert_messages(notifier_callback, message_checks):
 
     @notifier_callback
     def handle_message(message):
-        expected_msg = message_checks[0]
-        if message == expected_msg or isinstance(message, expected_msg):
-            message_checks.pop(0)
+        if len(message_checks) > 0:
+            expected_msg = message_checks[0]
+            if message == expected_msg or isinstance(message, expected_msg):
+                message_checks.pop(0)
 
         if message_checks == []:
             success_event.set()

tests/test_notifier.py

@@ -38,7 +38,7 @@ def start_server():
 
     session = requests.Session()
     session.mount(
-        "http",
+        "http://",
         HTTPAdapter(
             max_retries=Retry(
                 total=5,