Fix PendingDeprecationWarning: Task.all_tasks() is deprecated, use asyncio.all_tasks...

diff --git a/black.py b/black.py
index 200e15fbd071f897e4161f9cc5923fbbb96c9b8f..db1b2b6caa4192bd1a5e1479a680bf2b6f5689b5 100644 (file)
--- a/black.py
+++ b/black.py
@@ -3423,8 +3423,12 @@ def cancel(tasks: Iterable[asyncio.Task]) -> None:
 def shutdown(loop: BaseEventLoop) -> None:
     """Cancel all pending tasks on `loop`, wait for them, and close the loop."""
     try:
+        if sys.version_info[:2] >= (3, 7):
+            all_tasks = asyncio.all_tasks
+        else:
+            all_tasks = asyncio.Task.all_tasks
         # This part is borrowed from asyncio/runners.py in Python 3.7b2.
-        to_cancel = [task for task in asyncio.Task.all_tasks(loop) if not task.done()]
+        to_cancel = [task for task in all_tasks(loop) if not task.done()]
         if not to_cancel:
             return