asyncio: Replace "unittest.mock" with "mock" in unit tests

Use "from unittest import mock". It should simplify my work to merge new tests
in Trollius, because Trollius uses "mock" backport for Python 2.

Lib/test/test_asyncio/test_events.py

@@ -20,7 +20,7 @@ import threading
 import time
 import errno
 import unittest
-import unittest.mock
+from unittest import mock
 from test import support  # find_unused_port, IPV6_ENABLED, TEST_HOME_DIR
 
 
@@ -1812,7 +1812,7 @@ class HandleTests(unittest.TestCase):
             return args
 
         args = ()
-        h = asyncio.Handle(callback, args, unittest.mock.Mock())
+        h = asyncio.Handle(callback, args, mock.Mock())
         self.assertIs(h._callback, callback)
         self.assertIs(h._args, args)
         self.assertFalse(h._cancelled)
@@ -1844,15 +1844,15 @@ class HandleTests(unittest.TestCase):
         def callback():
             raise ValueError()
 
-        m_loop = unittest.mock.Mock()
-        m_loop.call_exception_handler = unittest.mock.Mock()
+        m_loop = mock.Mock()
+        m_loop.call_exception_handler = mock.Mock()
 
         h = asyncio.Handle(callback, (), m_loop)
         h._run()
 
         m_loop.call_exception_handler.assert_called_with({
             'message': test_utils.MockPattern('Exception in callback.*'),
-            'exception': unittest.mock.ANY,
+            'exception': mock.ANY,
             'handle': h
         })
 
@@ -1862,7 +1862,7 @@ class TimerTests(unittest.TestCase):
     def test_hash(self):
         when = time.monotonic()
         h = asyncio.TimerHandle(when, lambda: False, (),
-                                unittest.mock.Mock())
+                                mock.Mock())
         self.assertEqual(hash(h), hash(when))
 
     def test_timer(self):
@@ -1871,7 +1871,7 @@ class TimerTests(unittest.TestCase):
 
         args = ()
         when = time.monotonic()
-        h = asyncio.TimerHandle(when, callback, args, unittest.mock.Mock())
+        h = asyncio.TimerHandle(when, callback, args, mock.Mock())
         self.assertIs(h._callback, callback)
         self.assertIs(h._args, args)
         self.assertFalse(h._cancelled)
@@ -1887,10 +1887,10 @@ class TimerTests(unittest.TestCase):
 
         self.assertRaises(AssertionError,
                           asyncio.TimerHandle, None, callback, args,
-                          unittest.mock.Mock())
+                          mock.Mock())
 
     def test_timer_comparison(self):
-        loop = unittest.mock.Mock()
+        loop = mock.Mock()
 
         def callback(*args):
             return args
@@ -1935,7 +1935,7 @@ class TimerTests(unittest.TestCase):
 class AbstractEventLoopTests(unittest.TestCase):
 
     def test_not_implemented(self):
-        f = unittest.mock.Mock()
+        f = mock.Mock()
         loop = asyncio.AbstractEventLoop()
         self.assertRaises(
             NotImplementedError, loop.run_forever)
@@ -1995,13 +1995,13 @@ class AbstractEventLoopTests(unittest.TestCase):
             NotImplementedError, loop.remove_signal_handler, 1)
         self.assertRaises(
             NotImplementedError, loop.connect_read_pipe, f,
-            unittest.mock.sentinel.pipe)
+            mock.sentinel.pipe)
         self.assertRaises(
             NotImplementedError, loop.connect_write_pipe, f,
-            unittest.mock.sentinel.pipe)
+            mock.sentinel.pipe)
         self.assertRaises(
             NotImplementedError, loop.subprocess_shell, f,
-            unittest.mock.sentinel)
+            mock.sentinel)
         self.assertRaises(
             NotImplementedError, loop.subprocess_exec, f)
 
@@ -2009,7 +2009,7 @@ class AbstractEventLoopTests(unittest.TestCase):
 class ProtocolsAbsTests(unittest.TestCase):
 
     def test_empty(self):
-        f = unittest.mock.Mock()
+        f = mock.Mock()
         p = asyncio.Protocol()
         self.assertIsNone(p.connection_made(f))
         self.assertIsNone(p.connection_lost(f))
@@ -2055,7 +2055,7 @@ class PolicyTests(unittest.TestCase):
     def test_get_event_loop_calls_set_event_loop(self):
         policy = asyncio.DefaultEventLoopPolicy()
 
-        with unittest.mock.patch.object(
+        with mock.patch.object(
                 policy, "set_event_loop",
                 wraps=policy.set_event_loop) as m_set_event_loop:
 
@@ -2073,7 +2073,7 @@ class PolicyTests(unittest.TestCase):
         policy.set_event_loop(None)
         self.assertRaises(AssertionError, policy.get_event_loop)
 
-    @unittest.mock.patch('asyncio.events.threading.current_thread')
+    @mock.patch('asyncio.events.threading.current_thread')
     def test_get_event_loop_thread(self, m_current_thread):
 
         def f():