Tox: Cannot gen xml coverage report with py.test and pytest-cov

[pytoxbot]

• Bitbucket: https://bitbucket.org/hpk42/tox/issue/361
• Originally reported by: SDET_Liang
• Originally created at: 2016-09-08T09:52:29.799

With following tox.ini, coverage.xml is not generated, but .covearge is created.
The output is listed below.

tox.ini

commands = py.test ./tests --junitxml=unittest-{envname}.xml --cov=mypkg --cov-report xml

ouptut

py27 runtests: PYTHONHASHSEED='123456'
py27 runtests: commands[0] | py.test ./tests --junitxml=unittest-py27.xml --cov=mypkg --cov-report xml
============================= test session starts ==============================
platform linux2 -- Python 2.7.10, pytest-2.9.1, py-1.4.31, pluggy-0.3.1
rootdir: /data/jenkins/workspace/mypkg-unittest, inifile: 
plugins: cov-2.3.0

tests/test_sth.py ..........


 generated xml file: /data/jenkins/workspace/mypkg-unittest/unittest-py27.xml 

---------- coverage: platform linux2, python 2.7.10-final-0 ----------
Coverage XML written to file coverage.xml

========================== 10 passed in 21.87 seconds ==========================
___________________________________ summary ____________________________________
  py27: commands succeeded

[RonnyPfannschmidt]

@SDET_Liang the output claims the file was written, can you take a look at the folder called rootdir?

[hpk42]

it's likely rather about finding where it was written, and the original poster is not here, likely. so closing.

[ubmarco]

I'm having exactly the same problem - the file gets not written. And it is nowhere on my whole drive.
A workaround is to use absolute paths like this:
py.test --cov {envsitepackagesdir}/<package> --cov-report xml:{envdir}/../../coverage.xml --junitxml=unittest_{envname}.xml
But the issue is not related to tox because I have the same issue running pytest with the pytest-cov plugin from command line.

[obestwalter]

Hi @ubmarco, thanks for providing the workaround. As you say it is not a tox issue though, but doesn't hurt to have this here, for other seekers :)

[rydrman]

My tests were changing the current working directory to a temporary directory. It seems that this change messes up pytest-cov as it relies on the working directory to be where you ran the tests from. My fix was to simply add a simple pytest fixture with autouse=True which resets the current working directory after each test.