From 98fa332e334633d5559ff3963df0ab5c6108d8e1 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Thu, 17 Jul 2014 23:49:11 +0200 Subject: [PATCH] Issue #21247: Fix a race condition in test_send_signal() of asyncio Add a basic synchronization mechanism to wait until the child process is ready before sending it a signal. --- Lib/test/test_asyncio/test_subprocess.py | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/Lib/test/test_asyncio/test_subprocess.py b/Lib/test/test_asyncio/test_subprocess.py index d050458e7ff..5425d9bfd5e 100644 --- a/Lib/test/test_asyncio/test_subprocess.py +++ b/Lib/test/test_asyncio/test_subprocess.py @@ -108,11 +108,22 @@ class SubprocessMixin: @unittest.skipIf(sys.platform == 'win32', "Don't have SIGHUP") def test_send_signal(self): - args = PROGRAM_BLOCKED - create = asyncio.create_subprocess_exec(*args, loop=self.loop) + code = 'import time; print("sleeping", flush=True); time.sleep(3600)' + args = [sys.executable, '-c', code] + create = asyncio.create_subprocess_exec(*args, loop=self.loop, stdout=subprocess.PIPE) proc = self.loop.run_until_complete(create) - proc.send_signal(signal.SIGHUP) - returncode = self.loop.run_until_complete(proc.wait()) + + @asyncio.coroutine + def send_signal(proc): + # basic synchronization to wait until the program is sleeping + line = yield from proc.stdout.readline() + self.assertEqual(line, b'sleeping\n') + + proc.send_signal(signal.SIGHUP) + returncode = (yield from proc.wait()) + return returncode + + returncode = self.loop.run_until_complete(send_signal(proc)) self.assertEqual(-signal.SIGHUP, returncode) def prepare_broken_pipe_test(self):