gh-72889: remove redundant mock.Mock()._is_coroutine = False workarounds

[graingert]

these work-arounds were made redundant by python/asyncio#459

• Issue: Fix asyncio.iscoroutinefunction to handle Mock objects #72889

[graingert]

when asyncio.iscoroutinefunction was implemented as:

cpython/Lib/asyncio/coroutines.py

Lines 245 to 248 in 2f84144

	defiscoroutinefunction(func):
	"""Return True if func is a decorated coroutine function."""
	return (getattr(func, '_is_coroutine', False) or
	_inspect_iscoroutinefunction(func))

this meant

self.loop._add_reader=mock.Mock()
assertasyncio.iscoroutinefunction(self.loop._add_reader) isTrue# mock objects have a truthy _is_coroutine attribute!self.loop._add_reader._is_coroutine=Falseassertasyncio.iscoroutinefunction(self.loop._add_reader) isFalse# patching it works around the issue

however the implementation was changed to use a marker object:

cpython/Lib/asyncio/coroutines.py

Lines 16 to 23 in ec4745b

	# A marker for iscoroutinefunction.
	_is_coroutine=object()
	defiscoroutinefunction(func):
	"""Return True if func is a decorated coroutine function."""
	return (inspect.iscoroutinefunction(func) or
	getattr(func, '_is_coroutine', None) is_is_coroutine)

and so now the _is_coroutine = False work-around is redundant:

self.loop._add_reader=mock.Mock()
assertasyncio.iscoroutinefunction(self.loop._add_reader) isFalse# mock objects have an _is_coroutine but it's not the asyncio.coroutines._is_coroutine sentinelself.loop._add_reader._is_coroutine=Falseassertasyncio.iscoroutinefunction(self.loop._add_reader) isFalse# it's still False so the workaround is redundant

[graingert]

I don't think this needs a news entry

[gvanrossum]

Since this just changes tests and the tests pass, I think this is okay.

[miss-islington]

Thanks @graingert for the PR, and @gvanrossum for merging it 🌮🎉.. I'm working now to backport this PR to: 3.11.
🐍🍒⛏🤖

[bedevere-bot]

GH-94934 is a backport of this pull request to the 3.11 branch.