Clean up asyncio loop usage

cloudbot/bot.py

@@ -160,7 +160,7 @@ def __init__(
         self.db_engine = create_engine(db_path)
         database.configure(self.db_engine)
         self.db_executor_pool = ExecutorPool(
-            50, max_workers=1, thread_name_prefix="cloudbot-db"
+            50, max_workers=1, thread_name_prefix="cloudbot-db", loop=self.loop
         )
 
         logger.debug("Database system initialised.")

cloudbot/util/async_util.py

@@ -58,8 +58,7 @@ def run_coroutine_threadsafe(coro, loop):
     asyncio.run_coroutine_threadsafe(coro, loop)
 
 
-def create_future(loop=None):
-    loop = loop if loop is not None else asyncio.get_event_loop()
+def create_future(loop):
     return loop.create_future()
 
 

cloudbot/util/executor_pool.py

@@ -1,3 +1,4 @@
+from asyncio import AbstractEventLoop
 import logging
 import os
 import random
@@ -27,8 +28,8 @@ def __del__(self):
 
 class ExecutorPool:
     def __init__(
-        self, max_executors=None, executor_type=ThreadPoolExecutor, **kwargs
-    ):
+        self, max_executors=None, executor_type=ThreadPoolExecutor, *, loop:AbstractEventLoop, **kwargs
+    ) -> None:
         if max_executors is None:
             max_executors = (os.cpu_count() or 1) * 5
 
@@ -41,7 +42,7 @@ def __init__(
 
         self._executors = []
         self._free_executors = []
-        self._executor_waiter = create_future()
+        self._executor_waiter = create_future(loop)
 
     def get(self):
         return ExecutorWrapper(self, self._get())

tests/util/mock_bot.py

@@ -21,9 +21,13 @@ def __init__(
         db: Optional[MockDB] = None,
         base_dir=None,
     ):
-        self.db_executor_pool = ExecutorPool(
-            50, max_workers=1, thread_name_prefix="cloudbot-db"
-        )
+        if loop:
+            self.db_executor_pool = ExecutorPool(
+                50, max_workers=1, thread_name_prefix="cloudbot-db", loop=loop
+            )
+        else:
+            self.db_executor_pool = None
+
         self.old_db = None
         self.do_db_migrate = False
         self.loop = loop