asyncio: Fix pyflakes warnings: remove unused variables and imports

Lib/asyncio/test_utils.py

@@ -11,7 +11,6 @@ import sys
 import tempfile
 import threading
 import time
-import unittest
 from unittest import mock
 
 from http.server import HTTPServer

Lib/test/test_asyncio/test_base_events.py

@@ -7,7 +7,7 @@ import sys
 import time
 import unittest
 from unittest import mock
-from test.support import find_unused_port, IPV6_ENABLED
+from test.support import IPV6_ENABLED
 
 import asyncio
 from asyncio import base_events

Lib/test/test_asyncio/test_events.py

@@ -25,7 +25,6 @@ from test import support  # find_unused_port, IPV6_ENABLED, TEST_HOME_DIR
 
 
 import asyncio
-from asyncio import events
 from asyncio import selector_events
 from asyncio import test_utils
 
@@ -1648,13 +1647,12 @@ class SubprocessTestsMixin:
 
     def test_subprocess_wait_no_same_group(self):
         proto = None
-        transp = None
 
         @asyncio.coroutine
         def connect():
             nonlocal proto
             # start the new process in a new session
-            transp, proto = yield from self.loop.subprocess_shell(
+            _, proto = yield from self.loop.subprocess_shell(
                 functools.partial(MySubprocessProtocol, self.loop),
                 'exit 7', stdin=None, stdout=None, stderr=None,
                 start_new_session=True)

Lib/test/test_asyncio/test_selector_events.py

@@ -1,6 +1,5 @@
 """Tests for selector_events.py"""
 
-import collections
 import errno
 import gc
 import pprint
@@ -1378,7 +1377,7 @@ class SelectorSslWithoutSslTransportTests(unittest.TestCase):
     def test_ssl_transport_requires_ssl_module(self):
         Mock = mock.Mock
         with self.assertRaises(RuntimeError):
-            transport = _SelectorSslTransport(Mock(), Mock(), Mock(), Mock())
+            _SelectorSslTransport(Mock(), Mock(), Mock(), Mock())
 
 
 class SelectorDatagramTransportTests(unittest.TestCase):

Lib/test/test_asyncio/test_streams.py

@@ -1,6 +1,5 @@
 """Tests for streams.py."""
 
-import functools
 import gc
 import socket
 import unittest

Lib/test/test_asyncio/test_tasks.py

@@ -830,7 +830,7 @@ class TaskTests(unittest.TestCase):
                 v = yield from f
                 self.assertEqual(v, 'a')
 
-        res = loop.run_until_complete(asyncio.Task(foo(), loop=loop))
+        loop.run_until_complete(asyncio.Task(foo(), loop=loop))
 
     def test_as_completed_reverse_wait(self):
 
@@ -964,13 +964,9 @@ class TaskTests(unittest.TestCase):
         loop = test_utils.TestLoop(gen)
         self.addCleanup(loop.close)
 
-        sleepfut = None
-
         @asyncio.coroutine
         def sleep(dt):
-            nonlocal sleepfut
-            sleepfut = asyncio.sleep(dt, loop=loop)
-            yield from sleepfut
+            yield from asyncio.sleep(dt, loop=loop)
 
         @asyncio.coroutine
         def doit():

Lib/test/test_asyncio/test_unix_events.py

@@ -1376,19 +1376,16 @@ class ChildWatcherTestsMixin:
         # attach a new loop
         old_loop = self.loop
         self.loop = test_utils.TestLoop()
+        patch = mock.patch.object
 
-        with mock.patch.object(
-                old_loop,
-                "remove_signal_handler") as m_old_remove_signal_handler, \
-             mock.patch.object(
-                self.loop,
-                "add_signal_handler") as m_new_add_signal_handler:
+        with patch(old_loop, "remove_signal_handler") as m_old_remove, \
+             patch(self.loop, "add_signal_handler") as m_new_add:
 
             self.watcher.attach_loop(self.loop)
 
-            m_old_remove_signal_handler.assert_called_once_with(
+            m_old_remove.assert_called_once_with(
                 signal.SIGCHLD)
-            m_new_add_signal_handler.assert_called_once_with(
+            m_new_add.assert_called_once_with(
                 signal.SIGCHLD, self.watcher._sig_chld)
 
         # child terminates
@@ -1462,7 +1459,6 @@ class ChildWatcherTestsMixin:
     def test_close(self, m):
         # register two children
         callback1 = mock.Mock()
-        callback2 = mock.Mock()
 
         with self.watcher:
             self.running = True

Lib/test/test_asyncio/test_windows_events.py

@@ -8,7 +8,6 @@ if sys.platform != 'win32':
 import _winapi
 
 import asyncio
-from asyncio import test_utils
 from asyncio import _overlapped
 from asyncio import windows_events
 
@@ -50,7 +49,7 @@ class ProactorTests(unittest.TestCase):
         ADDRESS = r'\\.\pipe\test_double_bind-%s' % os.getpid()
         server1 = windows_events.PipeServer(ADDRESS)
         with self.assertRaises(PermissionError):
-            server2 = windows_events.PipeServer(ADDRESS)
+            windows_events.PipeServer(ADDRESS)
         server1.close()
 
     def test_pipe(self):