Pyenv-virtualenv: Running Tox inside a pyenv virutalenv

[andymccurdy]

It seems like you can't use Tox to test against multiple Python versions inside of a virtualenv created with pyenv-virtualenv. From what I can tell, this is because activating a pyenv-virtualenv sets the PYENV_VERSION to the named virtualenv, which makes all the other pythonX.Y shims invalid.

A complete example demonstrating this problem:

$> pyenv install 2.7.6
$> pyenv install 3.4.1
$> pyenv global 2.7.6 3.4.1
$> pyenv versions
  system
* 2.7.6 (set by /Users/andy/.pyenv/version)
* 3.4.1 (set by /Users/andy/.pyenv/version)

# NOTE, installing tox "globally" here and running it
# against 2.7.6 and 3.4.1 works fine because both
#2.7.6 and 3.4.1 are "activated" in the non-virtualenv
# environment

$> pyenv virtualenv 2.7.6 redis-py
$> pyenv activate redis-py
$> pyenv versions
  system
  2.7.6
  3.4.1
* redis-py (set by PYENV_VERSION environment variable)

# Now Tox (or any other program trying to call python3.4) will fail

$> python3.4
pyenv: python3.4: command not found

The `python3.4' command exists in these Python versions:
  3.4.1

I've gotten around this problem by using pyenv-virtualenvwrapper, which doesn't seem to use the pyenv versions system to create the virtualenv and doesn't set the PYENV_VERSION environment variable.

[yyuu]

In this case, you don't have to activate the virtualenv of redis-py.

Following example doesn't help?

## Setup CPython and virtualenv.
$ pyenv install 2.7.6
$ pyenv install 3.4.1
$ pyenv virtualenv 2.7.6 redis-py27
$ pyenv virtualenv 3.4.1 redis-py34
$ pyenv global redis-py27 redis-py34

## Setup tox.
$ pip install tox
$ pyenv rehash
$ cat <<EOF >setup.py
from setuptools import setup
setup(name="x")
EOF
$ cat <<EOF >tox.ini
[tox]
envlist = py27, py34
[testenv:py27]
basepython = python2.7
[testenv:py34]
basepython = python3.4
[testenv]
commands = python --version
EOF

## Then, run tox.
$ tox
GLOB sdist-make: /home/yamashita/x/setup.py
py27 inst-nodeps: /home/yamashita/x/.tox/dist/x-0.0.0.zip
py27 runtests: PYTHONHASHSEED='2368391035'
py27 runtests: commands[0] | python --version
Python 2.7.6
py34 inst-nodeps: /home/yamashita/x/.tox/dist/x-0.0.0.zip
py34 runtests: PYTHONHASHSEED='2368391035'
py34 runtests: commands[0] | python --version
Python 3.4.1
__________________________________________________________________________________ summary ___________________________________________________________________________________
  py27: commands succeeded
  py34: commands succeeded
  congratulations :)

[andymccurdy]

Perhaps I'm not understanding the "pyenv way". Your example seems to break whenever there's other dependencies. I did what you suggest above and changed a few things:

# AFTER pyenv global redis-py27 redis-py34
pip install hiredis    # a dependency used by my project


# tox.ini:
[tox]
envlist = py27, py34

[testenv:py27]
basepython = python2.7

[testenv:py34]
basepython = python3.4

[testenv]
commands = python foo.py 

# foo.py
from __future__ import print_function

try:
    import hiredis
except ImportError:
    print("import error")


# RUNNING TOX (notice the import errors being printed out)

$> tox
GLOB sdist-make: /Users/andy/tmp/setup.py
py27 inst-nodeps: /Users/andy/tmp/.tox/dist/z-0.0.0.zip
py27 runtests: PYTHONHASHSEED='1564301523'
py27 runtests: commands[0] | python foo.py
import error
py34 inst-nodeps: /Users/andy/tmp/.tox/dist/z-0.0.0.zip
py34 runtests: PYTHONHASHSEED='1564301523'
py34 runtests: commands[0] | python foo.py
import error
___________________________________ summary ____________________________________
  py27: commands succeeded
  py34: commands succeeded
  congratulations :)

Even weirder, I can successfully import hiredis in the REPL from python and python2.7, but not python3.4. Which makes me wonder why the tox py27 environment test failed.

[andymccurdy]

Sorry, I guess I should have included hiredis as one of the deps in tox.ini. That would fix this issue as tox maintains it's own idea of virtualenvs.

[andymccurdy]

Even so, it seems pretty painful to me to have to switch the pyenv global when I want to work on a different project.

e.g.,

# work on redis-py...
pyenv global redis-py27 redis-py34
# work on foobar...
pyenv global foobar27 foobar34

I'd rather just activate a single redis-py or foobar virtualenv. That worked with non-pyenv virtualenv and it works with pyenv-virtualenvwrapper.

[yyuu]

There is pyenv local it allows you to set project Python version per directory basis. See also https://github.com/yyuu/pyenv/blob/master/COMMANDS.md#pyenv-local

[andymccurdy]

This works. The biggest disconnect for me was I was thinking that pyenv virtualenv worked just like the Python virtualenv module. I made this assumption because they share the same name.

More documentation around this might be a good idea in the future. Specifically, something that says that when you activate a pyenv virtualenv that all the shims for other Python versions aren't available.

[yyuu]

Closing stale issue. Please reopen this if you still have a problem.

[marcgibbons]

@andymccurdy You can set up multiple envs as "local" which tox will then pickup

e.g.
pyenv local redis-py 2.7.6 3.4.1 ...

[alexjomin]

@andymccurdy You made my days !

should definitely be in the doc IMHO ! I will do a PR if's ok for you @yyuu

You can set up multiple envs as "local" which tox will then pickup
e.g.
pyenv local redis-py 2.7.6 3.4.1 ...