asyncio: Pass cancellation from wrapping Future to wrapped Future. By Saúl Ibarra Corretgé (mostly).
diff --git a/Lib/asyncio/futures.py b/Lib/asyncio/futures.py
index db27838..dd3e718 100644
--- a/Lib/asyncio/futures.py
+++ b/Lib/asyncio/futures.py
@@ -301,6 +301,8 @@
The other Future may be a concurrent.futures.Future.
"""
assert other.done()
+ if self.cancelled():
+ return
assert not self.done()
if other.cancelled():
self.cancel()
@@ -324,14 +326,17 @@
"""Wrap concurrent.futures.Future object."""
if isinstance(fut, Future):
return fut
-
assert isinstance(fut, concurrent.futures.Future), \
'concurrent.futures.Future is expected, got {!r}'.format(fut)
-
if loop is None:
loop = events.get_event_loop()
-
new_future = Future(loop=loop)
+
+ def _check_cancel_other(f):
+ if f.cancelled():
+ fut.cancel()
+
+ new_future.add_done_callback(_check_cancel_other)
fut.add_done_callback(
lambda future: loop.call_soon_threadsafe(
new_future._copy_state, fut))
diff --git a/Lib/test/test_asyncio/test_futures.py b/Lib/test/test_asyncio/test_futures.py
index ccea2ff..e35fcf0 100644
--- a/Lib/test/test_asyncio/test_futures.py
+++ b/Lib/test/test_asyncio/test_futures.py
@@ -241,6 +241,24 @@
f2 = futures.wrap_future(f1)
self.assertIs(m_events.get_event_loop.return_value, f2._loop)
+ def test_wrap_future_cancel(self):
+ f1 = concurrent.futures.Future()
+ f2 = futures.wrap_future(f1, loop=self.loop)
+ f2.cancel()
+ test_utils.run_briefly(self.loop)
+ self.assertTrue(f1.cancelled())
+ self.assertTrue(f2.cancelled())
+
+ def test_wrap_future_cancel2(self):
+ f1 = concurrent.futures.Future()
+ f2 = futures.wrap_future(f1, loop=self.loop)
+ f1.set_result(42)
+ f2.cancel()
+ test_utils.run_briefly(self.loop)
+ self.assertFalse(f1.cancelled())
+ self.assertEqual(f1.result(), 42)
+ self.assertTrue(f2.cancelled())
+
class FutureDoneCallbackTests(unittest.TestCase):