_blocking = False # proper use of future (yield vs yield from)
- _traceback = None # Used for Python 3.4 and later
- _tb_logger = None # Used for Python 3.3 only
+ _log_traceback = False # Used for Python 3.4 and later
+ _tb_logger = None # Used for Python 3.3 only
def __init__(self, *, loop=None):
"""Initialize the future.
if _PY34:
def __del__(self):
- if self._traceback is not None:
- logger.error('Future/Task exception was never retrieved:\n%s',
- ''.join(self._traceback))
+ if not self._log_traceback:
+ # set_exception() was not called, or result() or exception()
+ # has consumed the exception
+ return
+ exc = self._exception
+ logger.error('Future/Task exception was never retrieved:',
+ exc_info=(exc.__class__, exc, exc.__traceback__))
def cancel(self):
"""Cancel the future and schedule callbacks.
raise CancelledError
if self._state != _FINISHED:
raise InvalidStateError('Result is not ready.')
- self._traceback = None
+ self._log_traceback = False
if self._tb_logger is not None:
self._tb_logger.clear()
- self._tb_logger = None
+ self._tb_logger = None
if self._exception is not None:
raise self._exception
return self._result
raise CancelledError
if self._state != _FINISHED:
raise InvalidStateError('Exception is not set.')
- self._traceback = None
+ self._log_traceback = False
if self._tb_logger is not None:
self._tb_logger.clear()
- self._tb_logger = None
+ self._tb_logger = None
return self._exception
def add_done_callback(self, fn):
self._state = _FINISHED
self._schedule_callbacks()
if _PY34:
- self._traceback = traceback.format_exception(
- exception.__class__, exception, exception.__traceback__)
+ self._log_traceback = True
else:
self._tb_logger = _TracebackLogger(exception)
# Arrange for the logger to be activated after all callbacks