Previously, calling the strftime() method on a datetime object with a
trailing '%' in the format string would result in an exception. However,
this only occured when the datetime C module was being used; the python
implementation did not match this behavior. Datetime is now PEP-399
compliant, and will not throw an exception on a trailing '%'.

IDLE's test_squeezer.SqueezerTest.test_reload, added for issue 35196,
failed on both Gentoo buildbots.

The new functionality of Squeezer.reload() is also tested, along with some general
re-working of the tests in test_squeezer.py.

Format characters "%s" and "%V" in PyUnicode_FromFormat() and "%s" in PyBytes_FromFormat()
no longer read memory past the limit if precision is specified.

Add also tests for PyUnicode_FromFormat() and PyBytes_FromFormat()
with empty result.

Use the fast call convention for math functions atan2(),
copysign(), hypot() and remainder() and inline unpacking
arguments. This sped up them by 1.3--2.5 times.

Inline PyArg_UnpackTuple() and _PyArg_UnpackStack() in performance
sensitive code in the builtins and operator modules.

Argument clinic now generates fast inline code for
positional parsing, so the manually implemented type
check in math.dist can be removed.

This change separates the signal handling trigger in the eval loop from the "pending calls" machinery. There is no semantic change and the difference in performance is insignificant.

The change makes both components less confusing. It also eliminates the risk of changes to the pending calls affecting signal handling. This is particularly relevant for some upcoming pending calls changes I have in the works.

This fixes ShareableTypeTests.test_int() in Lib/test/test__xxsubinterpreters.py.

Use _PyArg_CheckPositional() and inlined code instead of
PyArg_UnpackTuple() and _PyArg_UnpackStack() if all parameters
are positional and use the "object" converter.

Fix memory leaks in asyncio ProactorEventLoop on overlapped operation
failures.

Changes:

* Implement the tp_traverse slot in the _overlapped.Overlapped type
  to help to break reference cycles and identify referrers in the
  garbage collector.
* Always clear overlapped on failure: not only set type to
  TYPE_NOT_STARTED, but release also resources.

Document that the time.CLOCK_MONOTONIC_RAW constant
is now also available on macOS 10.12.
Co-authored-by: Ricardo Fraile <rfraile@rfraile.eu>

* asyncio: __del__() keep reference to warnings.warn

The __del__() methods of asyncio classes now keep a strong reference
to the warnings.warn() to be able to display the ResourceWarning
warning in more cases. Ensure that the function remains available if
instances are destroyed late during Python shutdown (while module
symbols are cleared).

* Rename warn parameter to _warn

"_warn" name is a hint that it's not the regular warnings.warn()
function.

* _wait_for_handle(), _register() and _unregister() methods of
  IocpProactor now raise an exception if closed
* Add "closed" to IocpProactor.__repr__()
* Simplify IocpProactor.close()

Fix a memory leak in asyncio in the ProactorEventLoop when ReadFile()
or WSASend() overlapped operation fail immediately: release the
internal buffer.

Also adds extra steps to the CI build for Windows on Azure Pipelines to validate that the various layouts at least execute.

As in title, expose C `raise` function as `raise_function` in `signal` module. Also drop existing `raise_signal` in `_testcapi` module and replace all usages with new function.


https://bugs.python.org/issue35568

bpo-32622, bpo-35682: Fix asyncio.ProactorEventLoop.sendfile(): don't
attempt to set the result of an internal future if it's already done.

Fix asyncio _ProactorBasePipeTransport._force_close(): don't set the
result of _empty_waiter if it's already done.

This module is built by _asyncio.vcxproj and does not need to be included in pythoncore.

test.pythoninfo now logs information of all clocks, not only time.time() and
time.perf_counter().

test_asyncio/test_sendfile.py now resets the event loop policy using
tearDownModule() as done in other tests, to prevent a warning when
running tests on Windows.