Issue #28544: Implement asyncio.Task in C.
This implementation provides additional 10-20% speed boost for
asyncio programs.
The patch also fixes _asynciomodule.c to use Arguments Clinic, and
makes '_schedule_callbacks' an overridable method (as it was in 3.5).
diff --git a/Lib/asyncio/base_events.py b/Lib/asyncio/base_events.py
index 5880061..cc9994d 100644
--- a/Lib/asyncio/base_events.py
+++ b/Lib/asyncio/base_events.py
@@ -57,7 +57,7 @@
def _format_handle(handle):
cb = handle._callback
- if inspect.ismethod(cb) and isinstance(cb.__self__, tasks.Task):
+ if isinstance(getattr(cb, '__self__', None), tasks.Task):
# format the task
return repr(cb.__self__)
else:
diff --git a/Lib/asyncio/base_futures.py b/Lib/asyncio/base_futures.py
new file mode 100644
index 0000000..64f7845
--- /dev/null
+++ b/Lib/asyncio/base_futures.py
@@ -0,0 +1,70 @@
+__all__ = []
+
+import concurrent.futures._base
+import reprlib
+
+from . import events
+
+Error = concurrent.futures._base.Error
+CancelledError = concurrent.futures.CancelledError
+TimeoutError = concurrent.futures.TimeoutError
+
+
+class InvalidStateError(Error):
+ """The operation is not allowed in this state."""
+
+
+# States for Future.
+_PENDING = 'PENDING'
+_CANCELLED = 'CANCELLED'
+_FINISHED = 'FINISHED'
+
+
+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
+
+
+def _format_callbacks(cb):
+ """helper function for Future.__repr__"""
+ size = len(cb)
+ if not size:
+ cb = ''
+
+ def format_cb(callback):
+ return events._format_callback_source(callback, ())
+
+ if size == 1:
+ cb = format_cb(cb[0])
+ elif size == 2:
+ cb = '{}, {}'.format(format_cb(cb[0]), format_cb(cb[1]))
+ elif size > 2:
+ cb = '{}, <{} more>, {}'.format(format_cb(cb[0]),
+ size - 2,
+ format_cb(cb[-1]))
+ return 'cb=[%s]' % cb
+
+
+def _future_repr_info(future):
+ # (Future) -> str
+ """helper function for Future.__repr__"""
+ info = [future._state.lower()]
+ if future._state == _FINISHED:
+ if future._exception is not None:
+ info.append('exception={!r}'.format(future._exception))
+ else:
+ # use reprlib to limit the length of the output, especially
+ # for very long strings
+ result = reprlib.repr(future._result)
+ info.append('result={}'.format(result))
+ if future._callbacks:
+ info.append(_format_callbacks(future._callbacks))
+ if future._source_traceback:
+ frame = future._source_traceback[-1]
+ info.append('created at %s:%s' % (frame[0], frame[1]))
+ return info
diff --git a/Lib/asyncio/base_tasks.py b/Lib/asyncio/base_tasks.py
new file mode 100644
index 0000000..5f34434
--- /dev/null
+++ b/Lib/asyncio/base_tasks.py
@@ -0,0 +1,76 @@
+import linecache
+import traceback
+
+from . import base_futures
+from . import coroutines
+
+
+def _task_repr_info(task):
+ info = base_futures._future_repr_info(task)
+
+ if task._must_cancel:
+ # replace status
+ info[0] = 'cancelling'
+
+ coro = coroutines._format_coroutine(task._coro)
+ info.insert(1, 'coro=<%s>' % coro)
+
+ if task._fut_waiter is not None:
+ info.insert(2, 'wait_for=%r' % task._fut_waiter)
+ return info
+
+
+def _task_get_stack(task, limit):
+ frames = []
+ try:
+ # 'async def' coroutines
+ f = task._coro.cr_frame
+ except AttributeError:
+ f = task._coro.gi_frame
+ if f is not None:
+ while f is not None:
+ if limit is not None:
+ if limit <= 0:
+ break
+ limit -= 1
+ frames.append(f)
+ f = f.f_back
+ frames.reverse()
+ elif task._exception is not None:
+ tb = task._exception.__traceback__
+ while tb is not None:
+ if limit is not None:
+ if limit <= 0:
+ break
+ limit -= 1
+ frames.append(tb.tb_frame)
+ tb = tb.tb_next
+ return frames
+
+
+def _task_print_stack(task, limit, file):
+ extracted_list = []
+ checked = set()
+ for f in task.get_stack(limit=limit):
+ lineno = f.f_lineno
+ co = f.f_code
+ filename = co.co_filename
+ name = co.co_name
+ if filename not in checked:
+ checked.add(filename)
+ linecache.checkcache(filename)
+ line = linecache.getline(filename, lineno, f.f_globals)
+ extracted_list.append((filename, lineno, name, line))
+ exc = task._exception
+ if not extracted_list:
+ print('No stack for %r' % task, file=file)
+ elif exc is not None:
+ print('Traceback for %r (most recent call last):' % task,
+ file=file)
+ else:
+ print('Stack for %r (most recent call last):' % task,
+ file=file)
+ traceback.print_list(extracted_list, file=file)
+ if exc is not None:
+ for line in traceback.format_exception_only(exc.__class__, exc):
+ print(line, file=file, end='')
diff --git a/Lib/asyncio/coroutines.py b/Lib/asyncio/coroutines.py
index 1db7030..167c1e4 100644
--- a/Lib/asyncio/coroutines.py
+++ b/Lib/asyncio/coroutines.py
@@ -11,7 +11,7 @@
from . import compat
from . import events
-from . import futures
+from . import base_futures
from .log import logger
@@ -204,7 +204,7 @@
@functools.wraps(func)
def coro(*args, **kw):
res = func(*args, **kw)
- if (futures.isfuture(res) or inspect.isgenerator(res) or
+ if (base_futures.isfuture(res) or inspect.isgenerator(res) or
isinstance(res, CoroWrapper)):
res = yield from res
elif _AwaitableABC is not None:
diff --git a/Lib/asyncio/futures.py b/Lib/asyncio/futures.py
index b571130..d11d289 100644
--- a/Lib/asyncio/futures.py
+++ b/Lib/asyncio/futures.py
@@ -1,35 +1,32 @@
"""A Future class similar to the one in PEP 3148."""
-__all__ = ['CancelledError', 'TimeoutError',
- 'InvalidStateError',
- 'Future', 'wrap_future', 'isfuture'
- ]
+__all__ = ['CancelledError', 'TimeoutError', 'InvalidStateError',
+ 'Future', 'wrap_future', 'isfuture']
-import concurrent.futures._base
+import concurrent.futures
import logging
-import reprlib
import sys
import traceback
+from . import base_futures
from . import compat
from . import events
-# States for Future.
-_PENDING = 'PENDING'
-_CANCELLED = 'CANCELLED'
-_FINISHED = 'FINISHED'
-Error = concurrent.futures._base.Error
-CancelledError = concurrent.futures.CancelledError
-TimeoutError = concurrent.futures.TimeoutError
+CancelledError = base_futures.CancelledError
+InvalidStateError = base_futures.InvalidStateError
+TimeoutError = base_futures.TimeoutError
+isfuture = base_futures.isfuture
+
+
+_PENDING = base_futures._PENDING
+_CANCELLED = base_futures._CANCELLED
+_FINISHED = base_futures._FINISHED
+
STACK_DEBUG = logging.DEBUG - 1 # heavy-duty debugging
-class InvalidStateError(Error):
- """The operation is not allowed in this state."""
-
-
class _TracebackLogger:
"""Helper to log a traceback upon destruction if not cleared.
@@ -110,56 +107,6 @@
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
-
-
-def _format_callbacks(cb):
- """helper function for Future.__repr__"""
- size = len(cb)
- if not size:
- cb = ''
-
- def format_cb(callback):
- return events._format_callback_source(callback, ())
-
- if size == 1:
- cb = format_cb(cb[0])
- elif size == 2:
- cb = '{}, {}'.format(format_cb(cb[0]), format_cb(cb[1]))
- elif size > 2:
- cb = '{}, <{} more>, {}'.format(format_cb(cb[0]),
- size-2,
- format_cb(cb[-1]))
- return 'cb=[%s]' % cb
-
-
-def _future_repr_info(future):
- # (Future) -> str
- """helper function for Future.__repr__"""
- info = [future._state.lower()]
- if future._state == _FINISHED:
- if future._exception is not None:
- info.append('exception={!r}'.format(future._exception))
- else:
- # use reprlib to limit the length of the output, especially
- # for very long strings
- result = reprlib.repr(future._result)
- info.append('result={}'.format(result))
- if future._callbacks:
- info.append(_format_callbacks(future._callbacks))
- if future._source_traceback:
- frame = future._source_traceback[-1]
- info.append('created at %s:%s' % (frame[0], frame[1]))
- return info
-
-
class Future:
"""This class is *almost* compatible with concurrent.futures.Future.
@@ -212,7 +159,7 @@
if self._loop.get_debug():
self._source_traceback = traceback.extract_stack(sys._getframe(1))
- _repr_info = _future_repr_info
+ _repr_info = base_futures._future_repr_info
def __repr__(self):
return '<%s %s>' % (self.__class__.__name__, ' '.join(self._repr_info()))
@@ -247,10 +194,10 @@
if self._state != _PENDING:
return False
self._state = _CANCELLED
- self.__schedule_callbacks()
+ self._schedule_callbacks()
return True
- def __schedule_callbacks(self):
+ def _schedule_callbacks(self):
"""Internal: Ask the event loop to call all callbacks.
The callbacks are scheduled to be called as soon as possible. Also
@@ -352,7 +299,7 @@
raise InvalidStateError('{}: {!r}'.format(self._state, self))
self._result = result
self._state = _FINISHED
- self.__schedule_callbacks()
+ self._schedule_callbacks()
def set_exception(self, exception):
"""Mark the future done and set an exception.
@@ -369,7 +316,7 @@
"and cannot be raised into a Future")
self._exception = exception
self._state = _FINISHED
- self.__schedule_callbacks()
+ self._schedule_callbacks()
if compat.PY34:
self._log_traceback = True
else:
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py
index 8852aa5..5a43ef2 100644
--- a/Lib/asyncio/tasks.py
+++ b/Lib/asyncio/tasks.py
@@ -9,11 +9,10 @@
import concurrent.futures
import functools
import inspect
-import linecache
-import traceback
import warnings
import weakref
+from . import base_tasks
from . import compat
from . import coroutines
from . import events
@@ -93,18 +92,7 @@
futures.Future.__del__(self)
def _repr_info(self):
- info = super()._repr_info()
-
- if self._must_cancel:
- # replace status
- info[0] = 'cancelling'
-
- coro = coroutines._format_coroutine(self._coro)
- info.insert(1, 'coro=<%s>' % coro)
-
- if self._fut_waiter is not None:
- info.insert(2, 'wait_for=%r' % self._fut_waiter)
- return info
+ return base_tasks._task_repr_info(self)
def get_stack(self, *, limit=None):
"""Return the list of stack frames for this task's coroutine.
@@ -127,31 +115,7 @@
For reasons beyond our control, only one stack frame is
returned for a suspended coroutine.
"""
- frames = []
- try:
- # 'async def' coroutines
- f = self._coro.cr_frame
- except AttributeError:
- f = self._coro.gi_frame
- if f is not None:
- while f is not None:
- if limit is not None:
- if limit <= 0:
- break
- limit -= 1
- frames.append(f)
- f = f.f_back
- frames.reverse()
- elif self._exception is not None:
- tb = self._exception.__traceback__
- while tb is not None:
- if limit is not None:
- if limit <= 0:
- break
- limit -= 1
- frames.append(tb.tb_frame)
- tb = tb.tb_next
- return frames
+ return base_tasks._task_get_stack(self, limit)
def print_stack(self, *, limit=None, file=None):
"""Print the stack or traceback for this task's coroutine.
@@ -162,31 +126,7 @@
to which the output is written; by default output is written
to sys.stderr.
"""
- extracted_list = []
- checked = set()
- for f in self.get_stack(limit=limit):
- lineno = f.f_lineno
- co = f.f_code
- filename = co.co_filename
- name = co.co_name
- if filename not in checked:
- checked.add(filename)
- linecache.checkcache(filename)
- line = linecache.getline(filename, lineno, f.f_globals)
- extracted_list.append((filename, lineno, name, line))
- exc = self._exception
- if not extracted_list:
- print('No stack for %r' % self, file=file)
- elif exc is not None:
- print('Traceback for %r (most recent call last):' % self,
- file=file)
- else:
- print('Stack for %r (most recent call last):' % self,
- file=file)
- traceback.print_list(extracted_list, file=file)
- if exc is not None:
- for line in traceback.format_exception_only(exc.__class__, exc):
- print(line, file=file, end='')
+ return base_tasks._task_print_stack(self, limit, file)
def cancel(self):
"""Request that this task cancel itself.
@@ -316,6 +256,18 @@
self = None # Needed to break cycles when an exception occurs.
+_PyTask = Task
+
+
+try:
+ import _asyncio
+except ImportError:
+ pass
+else:
+ # _CTask is needed for tests.
+ Task = _CTask = _asyncio.Task
+
+
# wait() and as_completed() similar to those in PEP 3148.
FIRST_COMPLETED = concurrent.futures.FIRST_COMPLETED