pip install test dependencies for tox from setup.p

Question

I made my project with setuptools and I want to test it with tox. I listed dependencies in a variable and added to setup() parameter (tests_require and extras_require). My project needs to install all of the dependencies listed in tests_require to test but pip install is not installing them.

I tried this but it did not work:

install_command = pip install {opts} {packages}[tests]

How can I install test dependencies without having to manage multiple dependency lists (i.e. Having all dependencies listed in both test_requirements.txt and the tests_require variable)?

Answer 1

I've achieved this by committing a slight abuse of extra requirements. You were almost there trying the extras syntax, just that tests_require deps aren't automatically available that way.

With a setup.py like this:

from setuptools import setup

test_deps = [
    'coverage',
    'pytest',
]
extras = {
    'test': test_deps,
}

setup(
    # Other metadata...
    tests_require=test_deps,
    extras_require=extras,
)

You can then get the test dependencies installed with the extras syntax, e.g. from the project root directory:

$ pip install .[test]

Give that same syntax to Tox in tox.ini, no need to adjust the default install_command:

[testenv]
commands = {posargs:pytest}
deps = .[test]

Now you don't need to maintain the dependency list in two places, and they're expressed where they should be for a published package: in the packaging metadata instead of requirements.txt files.

It seems this little extras hack is not all that uncommon.

Answer 2

What you can do is have a single file (called test_requirements.txt) and list out the test dependencies like so:

dnspython==1.12.0
easydev==0.8.3
enum34==1.0.4
fabric==1.10.1
...

Then, in setup.py, parse and store the file contents in a list and pass that list to setup:

tests_require = [line.strip() for line in 
                 open('test_requirements.txt')
                 if line.strip() and not line.strip().startswith('--')]

setuptools.setup(
    ...
    tests_require=tests_require,
    ...
)

Answer 3

If you use the following command, Tox will install your test_requires before running the tests:

commands = {envpython} setup.py test

You'll also need to add to setup.py where are the tests with this:

test_suite="tests_module"

Finally, here's an answer for a similar question with a nice example.