[Python-checkins] cpython (3.4): asyncio: Make Tasks check if Futures are attached to the same event loop

Fri Dec 11 11:34:39 EST 2015

https://hg.python.org/cpython/rev/646bf7f5f019
changeset: 99529:646bf7f5f019
branch: 3.4
parent: 99526:36cd67ed9d4a
user: Yury Selivanov <yselivanov at sprymix.com>
date: Fri Dec 11 11:33:59 2015 -0500
summary:
 asyncio: Make Tasks check if Futures are attached to the same event loop
See https://github.com/python/asyncio/pull/303 for details
files:
 Lib/asyncio/tasks.py | 8 +++++++-
 Lib/test/test_asyncio/test_tasks.py | 15 +++++++++++++++
 2 files changed, 22 insertions(+), 1 deletions(-)

diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py
--- a/Lib/asyncio/tasks.py
+++ b/Lib/asyncio/tasks.py
@@ -251,7 +251,13 @@
 else:
 if isinstance(result, futures.Future):
 # Yielded Future must come from Future.__iter__().
- if result._blocking:
+ if result._loop is not self._loop:
+ self._loop.call_soon(
+ self._step,
+ RuntimeError(
+ 'Task {!r} got Future {!r} attached to a '
+ 'different loop'.format(self, result)))
+ elif result._blocking:
 result._blocking = False
 result.add_done_callback(self._wakeup)
 self._fut_waiter = result
diff --git a/Lib/test/test_asyncio/test_tasks.py b/Lib/test/test_asyncio/test_tasks.py
--- a/Lib/test/test_asyncio/test_tasks.py
+++ b/Lib/test/test_asyncio/test_tasks.py
@@ -76,6 +76,21 @@
 def setUp(self):
 self.loop = self.new_test_loop()
 
+ def test_other_loop_future(self):
+ other_loop = asyncio.new_event_loop()
+ fut = asyncio.Future(loop=other_loop)
+
+ @asyncio.coroutine
+ def run(fut):
+ yield from fut
+
+ try:
+ with self.assertRaisesRegex(RuntimeError,
+ r'Task .* got Future .* attached'):
+ self.loop.run_until_complete(run(fut))
+ finally:
+ other_loop.close()
+
 def test_task_class(self):
 @asyncio.coroutine
 def notmuch():
-- 
Repository URL: https://hg.python.org/cpython
