Improve stability of the proactor event loop, especially operations on
overlapped objects:
* Tulip issue 195: Don't call UnregisterWait() twice if a _WaitHandleFuture is
cancelled twice to fix a crash.
* IocpProactor.close(): cancel futures to cancel overlapped operations, instead
of cancelling directly overlapped operations. Future objects may not call
ov.cancel() if the future was cancelled or if the overlapped was already
cancelled. The cancel() method of the future may also catch exceptions. Log
also errors on cancellation.
* tests: rename "f" to "fut"
* Add a __repr__() method to IocpProactor
* Add a destructor to IocpProactor which closes it
* _OverlappedFuture.cancel() doesn't cancel the overlapped anymore if it is
done: if it is already cancelled or completed. Log also an error if the
cancellation failed.
* Add the address of the overlapped object in repr(_OverlappedFuture)
* _OverlappedFuture truncates the source traceback to hide the call to the
parent constructor (useless in debug).
terminal to not write the ANSI sequence "\033[1034h" into stdout. This sequence
is used on some terminal (ex: TERM=xterm-256color") to enable support of 8 bit
characters.
lines or narrowed for small screens.
Issie #19132: Turtledemo buttons no longer disappear when window is shrun.
Patch mostly by Lita Cho (21597) using idea from patch by Jan Kanis (18132).
Adds `load_package_tests` function to test.support, uses it in test_asyncio,
test_email, test_json, test_tools, test_importlib and all test_importlib
sub-packages to implement test discovery.
Since Python 3.3, the C signal handler writes the signal number into the wakeup
file descriptor and then schedules the Python call using Py_AddPendingCall().
asyncio uses the wakeup file descriptor to wake up the event loop, and relies
on Py_AddPendingCall() to schedule the final callback with call_soon().
If the C signal handler is called in a thread different than the thread of the
event loop, the loop is awaken but Py_AddPendingCall() was not called yet. In
this case, the event loop has nothing to do and go to sleep again.
Py_AddPendingCall() is called while the event loop is sleeping again and so the
final callback is not scheduled immediatly.
This patch changes how asyncio handles signals. Instead of relying on
Py_AddPendingCall() and the wakeup file descriptor, asyncio now only relies on
the wakeup file descriptor. asyncio reads signal numbers from the wakeup file
descriptor to call its signal handler.
If you want to handle the BrokenPipeError, you can easily reimplement
communicate().
Add also a unit test to ensure that stdin.write() + stdin.drain() raises
BrokenPipeError.