Assertions on nested comprehensions can give NameError #5370
Description
This test:
def test_nested_comprehension():
s = [[True, True], [True, True]]
assert all(e for row in s for e in row)
works fine in pytest 4.4.1 and 4.5.0. In pytest 4.6.1 it produces a NameError:
$ pytest
===================================================== test session starts =====================================================
platform darwin -- Python 3.7.3, pytest-4.6.1, py-1.8.0, pluggy-0.12.0
collected 1 item
test_it.py F [100%]
========================================================== FAILURES ===========================================================
__________________________________________________ test_nested_comprehension __________________________________________________
def test_nested_comprehension():
s = [[True, True], [True, True]]
> assert all(e for row in s for e in row)
E NameError: name 'e' is not defined
test_it.py:3: NameError
================================================== 1 failed in 0.06 seconds ===================================================
Pip list gives:
$ pip list
Package Version
------------------ -------
atomicwrites 1.3.0
attrs 19.1.0
importlib-metadata 0.17
more-itertools 7.0.0
packaging 19.0
pip 19.1.1
pluggy 0.12.0
py 1.8.0
pyparsing 2.4.0
pytest 4.6.1
setuptools 41.0.1
six 1.12.0
wcwidth 0.1.7
wheel 0.33.4
zipp 0.5.1