使用Conda和Tox运行测试时出错

Question

I am having trouble running tests with Tox while having virtual environments created with Conda. The steps to reproduce the error are below.

Download the repository (it is small) and cd to it:

git clone https://github.com/opensistemas-hub/osbrain.git
cd osbrain

Create the virtual environment with Conda:

conda create -n asdf python=3.5
source activate asdf
pip install tox

Try to run the tests (note that Python 3.5 is the only Python interpreter set in the tox.ini file):

tox

I would expect Tox to be able to use the Python 3.5 interpreter available in the Conda virtual environment to run the tests. However, instead, I am getting an error:

ERROR: The executable ~/osbrain/.tox/py35/bin/python3.5 is not 
functioning
ERROR: It thinks sys.prefix is '/usr' (should be '~/osbrain/.tox/py35')
ERROR: virtualenv is not compatible with this system or executable
Running virtualenv with interpreter ~/.miniconda3/envs/asdf/bin/python3.5

My question is: why am I getting that error and how can I avoid this? (ie: how could I run the tests locally for this project and using Tox?)

Answer 1

I managed to work around this by installing virtualenv through conda:

conda install virtualenv

It's not recommended to use virtualenv yourself (stick with conda environments). However, when tox looks for the package internally it will at least find a compatible version.

Answer 2

Virtualenv and conda/conda-env do not currently play nice together. See https://github.com/conda-forge/staged-recipes/issues/1139 and https://groups.google.com/a/continuum.io/forum/#!topic/conda/63B0jnPR-V4 .

UPDATE

Also related: https://bitbucket.org/hpk42/tox/issues/273/support-conda-envs-when-using-miniconda