[Python-checkins] bpo-35347: Fix test_socket.NonBlockingTCPTests (GH-10791)

Fri Nov 30 06:51:46 EST 2018

https://github.com/python/cpython/commit/af7e81f71858519de8d2bafcb38fce8cca86aa0a
commit: af7e81f71858519de8d2bafcb38fce8cca86aa0a
branch: 3.6
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: GitHub <noreply at github.com>
date: 2018年11月30日T03:51:42-08:00
summary:
bpo-35347: Fix test_socket.NonBlockingTCPTests (GH-10791)
testAccept() and testRecv() of test_socket.NonBlockingTCPTests have a
race condition: time.sleep() is used as a weak synchronization
primitive and the tests fail randomly on slow buildbots.
Use a reliable threading.Event to fix these tests.
Other changes:
* Replace send() with sendall()
* Expect specific BlockingIOError rather than generic OSError
* Add a timeout to select() in testAccept() and testRecv()
* Use addCleanup() to close sockets
* Use assertRaises()
(cherry picked from commit ebd5d6d6e6e4e751ba9c7534004aadfc27ba9265)
Co-authored-by: Victor Stinner <vstinner at redhat.com>
files:
M Lib/test/test_socket.py

diff --git a/Lib/test/test_socket.py b/Lib/test/test_socket.py
index fbbc9f9abfb0..6b7afba49d9e 100644
--- a/Lib/test/test_socket.py
+++ b/Lib/test/test_socket.py
@@ -32,6 +32,7 @@
 
 HOST = support.HOST
 MSG = 'Michael Gilfix was here\u1234\r\n'.encode('utf-8') ## test unicode string and carriage return
+MAIN_TIMEOUT = 60.0
 
 try:
 import _thread as thread
@@ -3870,6 +3871,7 @@ def _testSend(self):
 class NonBlockingTCPTests(ThreadedTCPSocketTest):
 
 def __init__(self, methodName='runTest'):
+ self.event = threading.Event()
 ThreadedTCPSocketTest.__init__(self, methodName=methodName)
 
 def testSetBlocking(self):
@@ -3944,22 +3946,27 @@ def _testInheritFlags(self):
 def testAccept(self):
 # Testing non-blocking accept
 self.serv.setblocking(0)
- try:
- conn, addr = self.serv.accept()
- except OSError:
- pass
- else:
- self.fail("Error trying to do non-blocking accept.")
- read, write, err = select.select([self.serv], [], [])
- if self.serv in read:
+
+ # connect() didn't start: non-blocking accept() fails
+ with self.assertRaises(BlockingIOError):
 conn, addr = self.serv.accept()
- self.assertIsNone(conn.gettimeout())
- conn.close()
- else:
+
+ self.event.set()
+
+ read, write, err = select.select([self.serv], [], [], MAIN_TIMEOUT)
+ if self.serv not in read:
 self.fail("Error trying to do accept after select.")
 
+ # connect() completed: non-blocking accept() doesn't block
+ conn, addr = self.serv.accept()
+ self.addCleanup(conn.close)
+ self.assertIsNone(conn.gettimeout())
+
 def _testAccept(self):
- time.sleep(0.1)
+ # don't connect before event is set to check
+ # that non-blocking accept() raises BlockingIOError
+ self.event.wait()
+
 self.cli.connect((HOST, self.port))
 
 def testConnect(self):
@@ -3974,25 +3981,32 @@ def _testConnect(self):
 def testRecv(self):
 # Testing non-blocking recv
 conn, addr = self.serv.accept()
+ self.addCleanup(conn.close)
 conn.setblocking(0)
- try:
- msg = conn.recv(len(MSG))
- except OSError:
- pass
- else:
- self.fail("Error trying to do non-blocking recv.")
- read, write, err = select.select([conn], [], [])
- if conn in read:
+
+ # the server didn't send data yet: non-blocking recv() fails
+ with self.assertRaises(BlockingIOError):
 msg = conn.recv(len(MSG))
- conn.close()
- self.assertEqual(msg, MSG)
- else:
+
+ self.event.set()
+
+ read, write, err = select.select([conn], [], [], MAIN_TIMEOUT)
+ if conn not in read:
 self.fail("Error during select call to non-blocking socket.")
 
+ # the server sent data yet: non-blocking recv() doesn't block
+ msg = conn.recv(len(MSG))
+ self.assertEqual(msg, MSG)
+
 def _testRecv(self):
 self.cli.connect((HOST, self.port))
- time.sleep(0.1)
- self.cli.send(MSG)
+
+ # don't send anything before event is set to check
+ # that non-blocking recv() raises BlockingIOError
+ self.event.wait()
+
+ # send data: recv() will no longer block
+ self.cli.sendall(MSG)
 
 @unittest.skipUnless(thread, 'Threading required for this test.')
 class FileObjectClassTestCase(SocketConnectedTest):
