Merge asyncio upstream.
diff --git a/Lib/asyncio/base_events.py b/Lib/asyncio/base_events.py
index 0174375..99f12b4 100644
--- a/Lib/asyncio/base_events.py
+++ b/Lib/asyncio/base_events.py
@@ -363,7 +363,7 @@
"""
self._check_closed()
- new_task = not isinstance(future, futures.Future)
+ new_task = not futures.isfuture(future)
future = tasks.ensure_future(future, loop=self)
if new_task:
# An exception is raised if the future didn't complete, so there
diff --git a/Lib/asyncio/coroutines.py b/Lib/asyncio/coroutines.py
index 71bc6fb..72ffb44 100644
--- a/Lib/asyncio/coroutines.py
+++ b/Lib/asyncio/coroutines.py
@@ -204,8 +204,8 @@
@functools.wraps(func)
def coro(*args, **kw):
res = func(*args, **kw)
- if isinstance(res, futures.Future) or inspect.isgenerator(res) or \
- isinstance(res, CoroWrapper):
+ if (futures.isfuture(res) or inspect.isgenerator(res) or
+ isinstance(res, CoroWrapper)):
res = yield from res
elif _AwaitableABC is not None:
# If 'func' returns an Awaitable (new in 3.5) we
diff --git a/Lib/asyncio/futures.py b/Lib/asyncio/futures.py
index edc13dc..bcd4d16 100644
--- a/Lib/asyncio/futures.py
+++ b/Lib/asyncio/futures.py
@@ -110,6 +110,16 @@
self.loop.call_exception_handler({'message': msg})
+def isfuture(obj):
+ """Check for a Future.
+
+ This returns True when obj is a Future instance or is advertising
+ itself as duck-type compatible by setting _asyncio_future_blocking.
+ See comment in Future for more details.
+ """
+ return getattr(obj, '_asyncio_future_blocking', None) is not None
+
+
class Future:
"""This class is *almost* compatible with concurrent.futures.Future.
@@ -423,15 +433,17 @@
If destination is cancelled, source gets cancelled too.
Compatible with both asyncio.Future and concurrent.futures.Future.
"""
- if not isinstance(source, (Future, concurrent.futures.Future)):
+ if not isfuture(source) and not isinstance(source,
+ concurrent.futures.Future):
raise TypeError('A future is required for source argument')
- if not isinstance(destination, (Future, concurrent.futures.Future)):
+ if not isfuture(destination) and not isinstance(destination,
+ concurrent.futures.Future):
raise TypeError('A future is required for destination argument')
- source_loop = source._loop if isinstance(source, Future) else None
- dest_loop = destination._loop if isinstance(destination, Future) else None
+ source_loop = source._loop if isfuture(source) else None
+ dest_loop = destination._loop if isfuture(destination) else None
def _set_state(future, other):
- if isinstance(future, Future):
+ if isfuture(future):
_copy_future_state(other, future)
else:
_set_concurrent_future_state(future, other)
@@ -455,7 +467,7 @@
def wrap_future(future, *, loop=None):
"""Wrap concurrent.futures.Future object."""
- if isinstance(future, Future):
+ if isfuture(future):
return future
assert isinstance(future, concurrent.futures.Future), \
'concurrent.futures.Future is expected, got {!r}'.format(future)
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py
index 3e200f6..35c945c 100644
--- a/Lib/asyncio/tasks.py
+++ b/Lib/asyncio/tasks.py
@@ -333,7 +333,7 @@
Note: This does not raise TimeoutError! Futures that aren't done
when the timeout occurs are returned in the second set.
"""
- if isinstance(fs, futures.Future) or coroutines.iscoroutine(fs):
+ if futures.isfuture(fs) or coroutines.iscoroutine(fs):
raise TypeError("expect a list of futures, not %s" % type(fs).__name__)
if not fs:
raise ValueError('Set of coroutines/Futures is empty.')
@@ -462,7 +462,7 @@
Note: The futures 'f' are not necessarily members of fs.
"""
- if isinstance(fs, futures.Future) or coroutines.iscoroutine(fs):
+ if futures.isfuture(fs) or coroutines.iscoroutine(fs):
raise TypeError("expect a list of futures, not %s" % type(fs).__name__)
loop = loop if loop is not None else events.get_event_loop()
todo = {ensure_future(f, loop=loop) for f in set(fs)}
@@ -538,7 +538,7 @@
If the argument is a Future, it is returned directly.
"""
- if isinstance(coro_or_future, futures.Future):
+ if futures.isfuture(coro_or_future):
if loop is not None and loop is not coro_or_future._loop:
raise ValueError('loop argument must agree with Future')
return coro_or_future
@@ -614,7 +614,7 @@
arg_to_fut = {}
for arg in set(coros_or_futures):
- if not isinstance(arg, futures.Future):
+ if not futures.isfuture(arg):
fut = ensure_future(arg, loop=loop)
if loop is None:
loop = fut._loop