`test_binascii.test_b2a_qp_a2b_qp_round_trip` flaky

[colesbury]

The hypothesis test test_b2a_qp_a2b_qp_round_trip checks that binascii.a2b_qp(binascii.b2a_qp(<value>)) gives the original value. However, this is not always true when istext=True (the default) and the value contains a mix of \n and \r\n new lines.

import binascii
>>>binascii.b2a_qp(b'\n\r\n', istext=True)
b'\n\n'
>>> binascii.a2b_qp(b'\n\n')
b'\n\n'

cpython/Lib/test/test_binascii.py

Lines 413 to 426 in 36c6178

	@hypothesis.given(
	binary=hypothesis.strategies.binary(),
	quotetabs=hypothesis.strategies.booleans(),
	istext=hypothesis.strategies.booleans(),
	header=hypothesis.strategies.booleans(),
	)
	def test_b2a_qp_a2b_qp_round_trip(self, binary, quotetabs, istext, header):
	converted = binascii.b2a_qp(
	self.type2test(binary),
	quotetabs=quotetabs, istext=istext, header=header,
	)
	restored = binascii.a2b_qp(self.type2test(converted), header=header)
	self.assertConversion(binary, converted, restored,
	quotetabs=quotetabs, istext=istext, header=header)

See also #64320

Seen in https://github.com/python/cpython/actions/runs/12200589926/job/34037087571

cc @sobolevn @picnixz

[colesbury]

@picnixz already filed the issue: #127696

[picnixz]

xD that's what happens when two people work on the same issue but not in the same room