How to run only one test in tox?

As written by jason meridth:

$ tox -e py35 -- project/tests/test_file.py::TestClassName::test_method

But the fine grain is mentioned by beluga.me in the comments: If you have a tox.ini file you might need to add the {posargs} to pytest in tox.ini:

[tox]
envlist = py35

[testenv]
deps =
    pytest
    pytest-cov
    pytest-pep8
commands =
    pip install -e .
    pytest {posargs}

Run one test with unittest

python3 -m unittest -q test_file.TestClassName

Run this command:

tox -epy27 -- test_name

for more information.