asyncio: Fix unix pipe transport 'repr' methods

Patch by Vincent Michel.
See also https://github.com/python/asyncio/pull/326

Lib/test/test_asyncio/test_events.py

@@ -1366,6 +1366,41 @@ class EventLoopTestsMixin:
         # extra info is available
         self.assertIsNotNone(proto.transport.get_extra_info('pipe'))
 
+    @unittest.skipUnless(sys.platform != 'win32',
+                         "Don't support pipes for Windows")
+    def test_unclosed_pipe_transport(self):
+        # This test reproduces the issue #314 on GitHub
+        loop = self.create_event_loop()
+        read_proto = MyReadPipeProto(loop=loop)
+        write_proto = MyWritePipeProto(loop=loop)
+
+        rpipe, wpipe = os.pipe()
+        rpipeobj = io.open(rpipe, 'rb', 1024)
+        wpipeobj = io.open(wpipe, 'w', 1024)
+
+        @asyncio.coroutine
+        def connect():
+            read_transport, _ = yield from loop.connect_read_pipe(
+                lambda: read_proto, rpipeobj)
+            write_transport, _ = yield from loop.connect_write_pipe(
+                lambda: write_proto, wpipeobj)
+            return read_transport, write_transport
+
+        # Run and close the loop without closing the transports
+        read_transport, write_transport = loop.run_until_complete(connect())
+        loop.close()
+
+        # These 'repr' calls used to raise an AttributeError
+        # See Issue #314 on GitHub
+        self.assertIn('open', repr(read_transport))
+        self.assertIn('open', repr(write_transport))
+
+        # Clean up (avoid ResourceWarning)
+        rpipeobj.close()
+        wpipeobj.close()
+        read_transport._pipe = None
+        write_transport._pipe = None
+
     @unittest.skipUnless(sys.platform != 'win32',
                          "Don't support pipes for Windows")
     # select, poll and kqueue don't support character devices (PTY) on Mac OS X