Tox WARNING:test command found but not installed in testenv

Question

I am using tox for my project.

Here is my tox.ini file:

[tox]
envlist =
    py27,
    lint,
    coverage

skipsdist = True

[testenv:py27]
deps = -rrequirements.txt
commands = python -m unittest discover -s ./tests

[testenv:coverage]
commands =
    coverage run --source=tests -m unittest discover -s tests/
    coverage html
    coverage report


[testenv:lint]
commands = pylint ./foo

whenever I run tox, everything is getting executed which basically is linting, coverage.

but Tox is displaying warning for everything.

WARNING:test command found but not installed in testenv
Maybe you forgot to specify a dependency? See also the whitelist_externals envconfig setting.

Everything succeeds, but it is still displaying warning and errors. Can anyone tell me to what I am doing wrong?

My requirements.txt file is this:

requests==2.18.4
JsonForm==0.0.2
jsonify==0.5
jsonschema==2.6.0
JsonSir==0.0.2
python-dateutil==1.5
DateTime==4.2
urllib3==1.22
contextlib2==0.5.5
mock==2.0.0
patch==1.16

Answer 1

Programs that you use in commands must either be installed in tox' virtual environment or whitelisted:

[tox]
envlist =
    py27,
    lint,
    coverage

skipsdist = True

[testenv:py27]
deps = -rrequirements.txt
whitelist_externals = python
commands = python -m unittest discover -s ./tests

[testenv:coverage]
whitelist_externals = coverage
commands =
    coverage run --source=tests -m unittest discover -s tests/
    coverage html
    coverage report


[testenv:lint]
whitelist_externals = pylint
commands = pylint ./foo