DEP: remove deprecated (and private) numpy.testing submodules.

[rgommers]

Removes these files that were deprecated since 1.15.0:

• numpy/testing/decorators.py
• numpy/testing/noseclasses.py
• numpy/testing/nosetester.py

This also resolves a failure in the recently introduced tests in test_public_api.py (see gh-14454). Closes gh-14566

[charris]

There are still folks using the NumPy nose framework so it may be a bit early to delete the files. Most of the linux distributions have patched versions of nose, so that still works. If we do remove the files there needs to be a release note.

[rgommers]

Nothing is gone, the correct imports are and have always been

from numpy.testing import Tester, run_module_suite, dec

These files were always private, they just missed an underscore.

[mattip]

There are still folks using the NumPy nose framework

@charris can we ping those projects to encourage them to deprecate the old imports?

[charris]

OK, looks like there are workarounds for any that need it. I'll do a wheels build after this is merged to check.

Thanks Ralf.

[charris]

OK, the travis builds are working, but the appveyor builds are failing. I don't know if that is related.

Note that a new version of setuptools was released a month ago. I suspect that maybe things were fixed to run that check, as the numpy version cannot be available before the build takes place.

[rgommers]

That Appveyor failure does not look related. It does look very odd though.

  File "C:\Python37-x64\lib\site-packages\setuptools\msvc.py", line 199, in msvc14_gen_lib_options
    if LegacyVersion(np.__version__) < LegacyVersion('1.11.2'):

Indeed, that can't be right, looks like a regression introduced in setuptools.

[rgommers]

Or it got triggered by @mattip's build_src changes

[charris]

I'm suspecting the latter, the code in setuptools is three years old.