Why is pytest aggressively escaping the message string provided to pytest.mark.filterwarnings?

[Asday]

I'd like to silence the warnings for a specific test which currently raises warnings about naive DateTimes in Django. The reason is because the test is creating noise which I don't have time to fix the underlying cause of.

My initial idea was to silence the warning, leave a comment explaining the silencing, and a comment in the offending code as a TODO.

I've run into issues, as I'd like to specifically ignore the warning about naive DateTimes. If other warnings turn up in the future, I want to see them.

From what I'm understand, pytest.mark.filterwarnings() takes a single string argument, which it splits on colons, escapes aggressively, and passes the results to warnings.filterwarnings().

My question is why is the escaping happening? My warning is as follows:

DateTimeField Model.field received a naive datetime (2018-08-04 00:00:00) while time zone support is active.

My .filterwarnings() mark is as follows:

@pytest.mark.filterwarnings(
    'ignore:'
    'DateTimeField.*received a naive datetime.*while time zone'
    ' support is active:'
    'RuntimeWarning'
)

The arguments that make it through to warnings.filterwarnings() are:

(Pdb) action
'ignore'
(Pdb) message
'DateTimeField\\.\\*received\\ a\\ naive\\ datetime\\.\\*while\\ time\\ zone\\ support\\ is\\ active'
(Pdb) category
<type 'exceptions.RuntimeWarning'>
(Pdb)

The message is re.compile()d in warnings.filterwarnings(), and that's what I'd like to leverage, but it appears pytest.mark.filterwarnings() has other ideas. Is there a reason for this? How do I get around this?

Pip list:

Package                  Version Location                                                                         
------------------------ ------- ---------------------------------------------------------------------------------
alabaster                0.7.11  
apipkg                   1.5     
asn1crypto               0.24.0  
atomicwrites             1.1.5   
attrs                    18.1.0  
Babel                    2.6.0   
bcrypt                   3.1.4   
beautifulsoup4           4.6.1   
cffi                     1.11.5  
cov-core                 1.15.0  
coverage                 3.7.1   
coveralls                0.5     
cryptography             2.3     
Django                   1.7.6   
django-braces            1.8.0   
django-colorful          1.1.0   
django-configurations    0.8     
django-dbbackup          2.3.2   
django-extensions        1.5.2   
django-fancypages        0.3.0
django-model-utils       3.1.2   
django-phonenumber-field 1.3.0   
django-qurl              0.1.1   
django-redis-cache       0.13.1  
django-rest-swagger      0.3.2   
django-secure            1.0.1   
django-sendfile          0.3.6   
django-shortuuidfield    0.1.3   
django-sslserver         0.15    
django-treebeard         4.3     
django-webtest           1.7.8   
django-widget-tweaks     1.3     
djangorestframework      2.4.5   
docopt                   0.6.2   
docutils                 0.12    
dropbox                  3.42    
enum34                   1.1.6   
execnet                  1.5.0   
Fabric                   1.14.0  
factory-boy              2.8.1   
Faker                    0.8.17  
fluffy                   0.0.0   /home/asday/code/src/github.com/[...]
funcsigs                 1.0.2   
futures                  3.2.0   
haversine                0.4.5   
idna                     2.7     
ipaddress                1.0.22  
ipython                  3.1.0   
Jinja2                   2.10    
MarkupSafe               1.0     
mock                     1.0.1   
more-itertools           4.3.0   
paramiko                 2.4.1   
pathlib2                 2.3.2   
pep8                     1.7.1   
phonenumberslite         8.9.10  
Pillow                   2.8.1   
pip                      18.0    
piprot                   0.9.10  
pkg-resources            0.0.0   
pluggy                   0.7.1   
psycopg2                 2.7.5   
pudb                     2015.2  
purl                     1.0.3   
py                       1.5.4   
pyasn1                   0.4.4   
pycparser                2.18    
Pygments                 2.2.0   
PyNaCl                   1.2.1   
pytest                   3.7.1   
pytest-cache             1.0     
pytest-cov               1.8.1   
pytest-django            3.1.2   
pytest-pep8              1.0.6   
pytest-splinter          1.7.7   
python-dateutil          2.4.2   
python-ntlm              1.1.0   
pytz                     2018.5  
PyYAML                   3.13    
qrcode                   5.1     
raven                    5.2.0   
redis                    2.10.6  
requests                 2.6.0   
requests-futures         0.9.7   
scandir                  1.8     
selenium                 2.53.5  
setuptools               40.0.0  
shortuuid                0.5.0   
six                      1.11.0  
snowballstemmer          1.2.1   
sorl-thumbnail           12.2    
Sphinx                   1.3.1   
sphinx-rtd-theme         0.1.7   
splinter                 0.7.3   
structlog                15.1.0  
text-unidecode           1.2     
unicodecsv               0.14.1  
Unidecode                1.0.22  
urllib3                  1.23    
urwid                    2.0.1   
uWSGI                    2.0.15  
waitress                 1.1.0   
WebOb                    1.8.2   
WebTest                  2.0.18  
Werkzeug                 0.10.4  
wheel                    0.31.1  

pytest version 3.7.1. Operating system Linux Mint 18.

[RonnyPfannschmidt]

CC @nicoddemus

https://github.com/pytest-dev/pytest/blob/master/src/_pytest/warnings.py#L68 uses the warnings module _setoption instead of pytests own _setoption

they differ in escaping

its not clear to my why we use them inconsistently - we clearly copied it from the warnings module since it escapes

[RonnyPfannschmidt]

#2598 introduced this - it seems like a mistake

[Asday]

Link to the current commit for future posterity.

[RonnyPfannschmidt]

@Asday wrong commit - the pr got the right one however

[nicoddemus]

Fixed by #3931