Description
Problem statement
Let's say there are multiple environments for different tests, like flake8, unit, sphinx and so on, but one would like to share the same virtual environment between them. This because their additional dependencies compared to the install_requires of the main application are small and this allows to reduce the space used and the time required to run the tests.
At the same time the application must be tested across multiple Python versions, so let's say this is the list of environments:
[tox]
envlist = py{34,35,36}-{flake8,unit,unit-min,bandit,prospector,sphinx}And one would like to have six virtualenvs:
py34-tests
py35-tests
py36-tests
py34-tests-min # To test with the minimum version of dependencies
py35-tests-min
py36-tests-min
At the best of my understanding, right now the only way to achieve this is to manually expand the envlist matrix and for each one create a [testenv:envname] block in the tox.ini file with the envdir assignement.
Proposed change
Like it works already for deps and commands, the proposal is to add support also for the envdir property to be set with factor-based values like:
[testenv]
envdir =
py34: py34-tests
py35: py35-tests
py36: py36-tests
py34-min: py34-tests-min # matches only environments that have both 'py34' and 'min' factors
py35-min: py35-tests-min
py36-min: py36-tests-minClearly there is a decision to make in case more than one factor matches an environment, given that the envdir can be only one, there are basically three possible behaviours:
- the one with more factors matching wins, in case of tie, first or last win. [preferred]
- first win
- last win
- raise an error