Add BaseSelectorEventLoopTests.test_accept_connection_skip_connectionabortederror to test graceful handling of ConnectionAbortedError

Author: jb2170

Lib/test/test_asyncio/test_selector_events.py

@@ -364,6 +364,31 @@ def test_accept_connection_multiple(self):
         self.loop.run_until_complete(asyncio.sleep(0))
         self.assertEqual(sock.accept.call_count, backlog)
 
+    def test_accept_connection_skip_connectionabortederror(self):
+        sock = mock.Mock()
+
+        def mock_sock_accept():
+            # mock accept(2) returning -ECONNABORTED every-other
+            # time that it's called. This applies most to OpenBSD
+            # whose sockets generate this errno more reproducibly than
+            # Linux and other OSs.
+            if sock.accept.call_count % 2 == 0:
+                raise ConnectionAbortedError
+            return (mock.Mock(), mock.Mock())
+
+        sock.accept.side_effect = mock_sock_accept
+        backlog = 100
+        # test that _accept_connection's loop calls sock.accept
+        # all 100 times, continuing past ConnectionAbortedError
+        # instead of unnecessarily returning early
+        mock_obj = mock.patch.object
+        with mock_obj(self.loop, '_accept_connection2') as accept2_mock:
+            self.loop._accept_connection(
+                mock.Mock(), sock, backlog=backlog)
+        # as in test_accept_connection_multiple avoid task pending
+        # warnings by using asyncio.sleep(0)
+        self.loop.run_until_complete(asyncio.sleep(0))
+        self.assertEqual(sock.accept.call_count, backlog)
 
 class SelectorTransportTests(test_utils.TestCase):