[Python-checkins] GH-93850: Fix test_asyncio exception ignored tracebacks (#93854)

[vstinner]

https://github.com/python/cpython/commit/b415c5f1aa29259d5d18a5d85b9365430614383a
commit: b415c5f1aa29259d5d18a5d85b9365430614383a
branch: main
author: Kumar Aditya <59607654+kumaraditya303 at users.noreply.github.com>
committer: vstinner <vstinner at python.org>
date: 2022-06-15T16:41:47+02:00
summary:

GH-93850: Fix test_asyncio exception ignored tracebacks (#93854)

files:
M Lib/test/test_asyncio/test_runners.py

diff --git a/Lib/test/test_asyncio/test_runners.py b/Lib/test/test_asyncio/test_runners.py
index 94d449f479184..7780a5f15e1b4 100644
--- a/Lib/test/test_asyncio/test_runners.py
+++ b/Lib/test/test_asyncio/test_runners.py
@@ -44,6 +44,9 @@ class BaseTest(unittest.TestCase):
     def new_loop(self):
         loop = asyncio.BaseEventLoop()
         loop._process_events = mock.Mock()
+        # Mock waking event loop from select
+        loop._write_to_self = mock.Mock()
+        loop._write_to_self.return_value = None
         loop._selector = mock.Mock()
         loop._selector.select.return_value = ()
         loop.shutdown_ag_run = False