asyncio: Fix unix pipe transport 'repr' methods

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

Lib/asyncio/unix_events.py

@@ -329,14 +329,17 @@ class _UnixReadPipeTransport(transports.ReadTransport):
         elif self._closing:
             info.append('closing')
         info.append('fd=%s' % self._fileno)
-        if self._pipe is not None:
+        selector = getattr(self._loop, '_selector', None)
+        if self._pipe is not None and selector is not None:
             polling = selector_events._test_selector_event(
-                          self._loop._selector,
+                          selector,
                           self._fileno, selectors.EVENT_READ)
             if polling:
                 info.append('polling')
             else:
                 info.append('idle')
+        elif self._pipe is not None:
+            info.append('open')
         else:
             info.append('closed')
         return '<%s>' % ' '.join(info)
@@ -453,9 +456,10 @@ class _UnixWritePipeTransport(transports._FlowControlMixin,
         elif self._closing:
             info.append('closing')
         info.append('fd=%s' % self._fileno)
-        if self._pipe is not None:
+        selector = getattr(self._loop, '_selector', None)
+        if self._pipe is not None and selector is not None:
             polling = selector_events._test_selector_event(
-                          self._loop._selector,
+                          selector,
                           self._fileno, selectors.EVENT_WRITE)
             if polling:
                 info.append('polling')
@@ -464,6 +468,8 @@ class _UnixWritePipeTransport(transports._FlowControlMixin,
 
             bufsize = self.get_write_buffer_size()
             info.append('bufsize=%s' % bufsize)
+        elif self._pipe is not None:
+            info.append('open')
         else:
             info.append('closed')
         return '<%s>' % ' '.join(info)

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