Testing guideline page is obsolete and not built in main docs

As per @rgommers’s advice, I am moving scipy/scipy#8606 to here.

The numpy testing guideline does not appear to be built with the other docs. It renders adequately on GitHub (https://github.com/numpy/numpy/blob/master/doc/TESTS.rst.txt), but seems out of place.

This is noticeable in particular because the scipy docs link to the GitHub page. The section on unit tests under the “Contributing New Code” section of the “Contributing to SciPy” page (http://scipy.github.io/devdocs/hacking.html#contributing-new-code) has a link to the “testing guidelines”, which points here.

Given that this page (probably among others) is important enough to link across projects, it would probably be a good idea to include it in the generated docs.

On top of the fact that the page is missing, it still refers to the old nose testing setup, and should probably be updated to include the switchover to py.test.

[pv]

pip install -e pretty much requires virtualenv, otherwise it you’ll mess up your production environment.

[mattip]

It would be nice if someday we could move towards git clean -xfd; pip install -e . --upgrade ; pytest -m "not slow" for running tests in place, which works today. We should tweak our conftests.py so the slow tests are not run by default. IMO maintaining a runtests.py is a burden and can get in the way of the testing tool’s progress over time, but it will be a while till we can change this.

Pandas made the move to pytest recently, but their documentation still mentions nose testing. Maybe we could learn from their conftest.py and some of the pull requests marked with Testing and pytest

Edit: soften tone about runtests.py