Method test_drain_raises

Lib/test/test_asyncio/test_streams.py:930–971

(self)

        self.loop.run_until_complete(main())

    def test_drain_raises(self):
        # See http://bugs.python.org/issue25441

        # This test should not use asyncio for the mock server; the
        # whole point of the test is to test for a bug in drain()
        # where it never gives up the event loop but the socket is
        # closed on the  server side.

        messages = []
        self.loop.set_exception_handler(lambda loop, ctx: messages.append(ctx))
        q = queue.Queue()

        def server():
            # Runs in a separate thread.
            with socket.create_server(('localhost', 0)) as sock:
                addr = sock.getsockname()
                q.put(addr)
                clt, _ = sock.accept()
                clt.close()

        async def client(host, port):
            reader, writer = await asyncio.open_connection(host, port)

            while True:
                writer.write(b"foo\n")
                await writer.drain()

        # Start the server thread and wait for it to be listening.
        thread = threading.Thread(target=server)
        thread.daemon = True
        thread.start()
        addr = q.get()

        # Should not be stuck in an infinite loop.
        with self.assertRaises((ConnectionResetError, ConnectionAbortedError,
                                BrokenPipeError)):
            self.loop.run_until_complete(client(*addr))

        # Clean up the thread.  (Only on success; on failure, it may
        # be stuck in accept().)
        thread.join()
        self.assertEqual([], messages)

    def test___repr__(self):
        stream = asyncio.StreamReader(loop=self.loop)