If the point is just to be able to test the existing API better, no PEP is needed, right? It would be an unsupported, undocumented API.

On Wed, Dec 6, 2017 at 7:22 PM, Nick Coghlan <ncoghlan@gmail.com> wrote:
On 7 December 2017 at 12:46, Guido van Rossum <guido@python.org> wrote:
> So you're okay with putting this off till (at least) 3.8? That sounds good
> to me, given that I'd like to go on vacation soon.

Eric reminded me off-list that we'd like to at least add the lower
level _interpreters API for the benefit of the test suite - right now,
all of our subinterpreter testing needs to be run through either
test_embed or test_capi, which is annoying enough that we end up
simply not testing the subinterpreter functionality properly (in
practice, we're relying heavily on the regression test suites for
mod_wsgi and JEP to find any problems we inadvertently introduce when
refactoring CPython's internals).

If we were to put that under test.support._interpreters for 3.7, we'd
be able to make it clear that we're in "Even more experimental than
provisional API status would account for" territory, while still
enabling the improved testing and accessibility for experimentation
that we're after in order to make some better informed API design
proposals for Python 3.8.


Nick Coghlan   |   ncoghlan@gmail.com   |   Brisbane, Australia

--Guido van Rossum (python.org/~guido)