Difference between multiple context managers in Windows and Linux #734
Description
Summary
I have some code which looks like:
with ( # Line 320
fn1(args1) as thing1,
fn2(args2) as thing2,
):
...I have some unit tests which run under Linux and (on the CI) under Windows. The command-line is python3 -m pytest --cov --cov-report term-missing.
Expected vs actual result
The expected result is that the coverage report should be the same on both platforms. Specifically that 100% branch coverage is achieved (despite that nothing mocks fn1 or fn2 raising an exception).
The actual result is that Linux achieves 100% coverage, but Windows reports that 320->exit is not covered.
Reproducer
Apologies, but I am not confident that this section is going to be entirely accurate. I don't have a Windows machine myself, so I can't readily obtain the required information for Windows. (It should be the same on both Windows and Linux, but obviously if one is looking for an explanation of different behaviour on the two platforms, different versions of something are the first place to look.)
Versions
$ pip list
Package Version Editable project location
------------------------------------- ------------------------ ------------------------------------------------------------------------------------
appdirs 1.4.4
asn1 2.7.0
asn1crypto 1.5.1
astroid 3.0.1
async-timeout 4.0.3
attrs 23.1.0
bcrypt 4.0.1
build 1.2.1
certifi 2024.8.30
certvalidator 1.0.0
cffi 1.16.0
chardet 5.2.0
charset-normalizer 3.3.2
click 8.1.7
configparser 5.3.0
coverage 7.10.7
coverage-conditional-plugin 0.9.0
dbus-next 0.2.3
dill 0.3.7
ecdsa 0.18.0
enum-compat 0.0.3
exceptiongroup 1.1.3
fdt 0.3.3
filelock 3.13.1
gitdb 4.0.10
GitPython 3.1.31
idna 3.10
ifaddr 0.2.0
iniconfig 2.0.0
isort 5.12.0
jedi 0.19.1
lazy-object-proxy 1.9.0
mccabe 0.7.0
mock 5.1.0
mypy 1.15.0
mypy-extensions 1.0.0
<redacted>
numpy 1.26.0
packaging 24.0
paramiko 3.4.1
parso 0.8.3
pbr 6.0.0
pefile 2023.2.7
pep517 0.13.0
pexpect 4.9.0
pip 23.3.2
platformdirs 4.3.6
pluggy 1.3.0
prompt-toolkit 3.0.41
psutil 5.9.4 /home/mbonner/git/main/build-host-linux/psutil
ptpython 3.0.23
ptyprocess 0.7.0
py 1.11.0
pycparser 2.22
pycryptodomex 3.20.0
pydantic 1.10.21
pyelftools 0.31
Pygments 2.16.1
pylint 3.0.2
PyNaCl 1.5.0
pyparsing 3.1.1
pyproject_hooks 1.1.0
pyscard 2.0.7
pyserial 3.5
pytest 7.4.3
pytest-asyncio 0.23.8
pytest-cov 4.1.0
pytest-mock 3.12.0
pytest-timeout 2.1.0
pytestdiv 0.3.1
PyYAML 6.0.1
requests 2.32.5
setuptools 79.0.1
six 1.17.0
smmap 5.0.0
toml 0.10.2
tomli 2.0.1
tomlkit 0.12.3
types-mock 5.1.0.2
types-PyYAML 6.0.12.12
types-requests 2.31.0.10
types-urllib3 1.26.25.14
typing_extensions 4.8.0
urllib3 2.5.0
wcwidth 0.2.10
wheel 0.45.1
wrapt 1.16.0
wxPython 4.2.2
zeroconf 0.147.0
[notice] A new release of pip is available: 23.3.2 -> 25.3
[notice] To update, run: pip install --upgrade pip
Python version: Python 3.11.14 (this is the same on Windows)
On windows:
platform win32 -- Python 3.11.14, pytest-7.4.3, pluggy-1.3.0
plugins: pytestdiv-0.3.1, asyncio-0.23.8, cov-4.1.0, mock-3.12.0, timeout-2.1.0, internal_pytest-0.1.1
On linux:
platform linux -- Python 3.11.14, pytest-7.4.3, pluggy-1.3.0
plugins: asyncio-0.23.8, mock-3.12.0, pytestdiv-0.3.1, timeout-2.1.0, cov-4.1.0, internal_pytest-0.1.1
Config
pytest.ini
[pytest]
log_cli_level = INFO
filterwarnings =
error
.coveragerc-linux
# see https://coverage.readthedocs.io/en/coverage-5.1/config.html
[run]
branch = True
# include top level namespace modules/packages we ship
source =
our.package
omit =
*/windows/*.py
[report]
fail_under = 100
# Regexes for lines to exclude from consideration
exclude_lines =
# exclude # pragma: no cover
pragma: no cover
# Don't complain about missing debug-only code:
def __repr__
# Don't complain if tests don't hit defensive assertion code:
raise AssertionError
raise NotImplementedError
# Don't complain about not running Windows-only code:
if sys.platform == 'win32':
.coveragerc-windows
# see https://coverage.readthedocs.io/en/coverage-5.1/config.html
[run]
branch = True
# include top level namespace modules/packages we ship
source = our.package
omit =
*/linux/*.py
[report]
fail_under = 100
# Regexes for lines to exclude from consideration
exclude_lines =
# exclude # pragma: no cover
pragma: no cover
# A pragma for code which simply isn't relevant on Windows.
pragma: no-coverage-windows
# Don't complain about missing debug-only code:
def __repr__
# Don't complain if tests don't hit defensive assertion code:
raise AssertionError
raise NotImplementedError
# Don't complain about not running Linux-only code:
if sys.platform.startswith\('linux'\):
Code
See above.