Closes #22922: More EventLoop methods fail if the loop is closed. Initial patch

written by Torsten Landschoff.

create_task(), call_at(), call_soon(), call_soon_threadsafe() and
run_in_executor() now raise an error if the event loop is closed.

Lib/asyncio/base_events.py

@@ -177,6 +177,7 @@ class BaseEventLoop(events.AbstractEventLoop):
 
         Return a task object.
         """
+        self._check_closed()
         task = tasks.Task(coro, loop=self)
         if task._source_traceback:
             del task._source_traceback[-1]
@@ -360,6 +361,7 @@ class BaseEventLoop(events.AbstractEventLoop):
         if (coroutines.iscoroutine(callback)
         or coroutines.iscoroutinefunction(callback)):
             raise TypeError("coroutines cannot be used with call_at()")
+        self._check_closed()
         if self._debug:
             self._assert_is_current_event_loop()
         timer = events.TimerHandle(when, callback, args, self)
@@ -390,6 +392,7 @@ class BaseEventLoop(events.AbstractEventLoop):
             raise TypeError("coroutines cannot be used with call_soon()")
         if self._debug and check_loop:
             self._assert_is_current_event_loop()
+        self._check_closed()
         handle = events.Handle(callback, args, self)
         if handle._source_traceback:
             del handle._source_traceback[-1]
@@ -426,6 +429,7 @@ class BaseEventLoop(events.AbstractEventLoop):
         if (coroutines.iscoroutine(callback)
         or coroutines.iscoroutinefunction(callback)):
             raise TypeError("coroutines cannot be used with run_in_executor()")
+        self._check_closed()
         if isinstance(callback, events.Handle):
             assert not args
             assert not isinstance(callback, events.TimerHandle)

Lib/asyncio/unix_events.py

@@ -71,6 +71,7 @@ class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop):
         or coroutines.iscoroutinefunction(callback)):
             raise TypeError("coroutines cannot be used with add_signal_handler()")
         self._check_signal(sig)
+        self._check_closed()
         try:
             # set_wakeup_fd() raises ValueError if this is not the
             # main thread.  By calling it early we ensure that an

Lib/test/test_asyncio/test_events.py

@@ -226,7 +226,8 @@ class EventLoopTestsMixin:
 
     def tearDown(self):
         # just in case if we have transport close callbacks
-        test_utils.run_briefly(self.loop)
+        if not self.loop.is_closed():
+            test_utils.run_briefly(self.loop)
 
         self.loop.close()
         gc.collect()
@@ -1434,6 +1435,38 @@ class EventLoopTestsMixin:
         with self.assertRaises(RuntimeError):
             self.loop.run_until_complete(coro)
 
+    def test_close(self):
+        self.loop.close()
+
+        @asyncio.coroutine
+        def test():
+            pass
+
+        func = lambda: False
+        coro = test()
+        self.addCleanup(coro.close)
+
+        # operation blocked when the loop is closed
+        with self.assertRaises(RuntimeError):
+            self.loop.run_forever()
+        with self.assertRaises(RuntimeError):
+            fut = asyncio.Future(loop=self.loop)
+            self.loop.run_until_complete(fut)
+        with self.assertRaises(RuntimeError):
+            self.loop.call_soon(func)
+        with self.assertRaises(RuntimeError):
+            self.loop.call_soon_threadsafe(func)
+        with self.assertRaises(RuntimeError):
+            self.loop.call_later(1.0, func)
+        with self.assertRaises(RuntimeError):
+            self.loop.call_at(self.loop.time() + .0, func)
+        with self.assertRaises(RuntimeError):
+            self.loop.run_in_executor(None, func)
+        with self.assertRaises(RuntimeError):
+            self.loop.create_task(coro)
+        with self.assertRaises(RuntimeError):
+            self.loop.add_signal_handler(signal.SIGTERM, func)
+
 
 class SubprocessTestsMixin: