cowardly pypy bug

[obestwalter]

I haven't had time to look closer yet, but I am pretty sure that there is a problem with our "do not delete folders that don't look like venvs" protection.

When testing tox-direct it regularly occurs that this is shown:

tox -r -e pypy
GLOB sdist-make: /home/ob/oss/tox-dev/tox-direct/setup.py
pypy recreate: /home/ob/oss/tox-dev/tox-direct/.tox/pypy
ERROR: cowardly refusing to delete `envdir` (it does not look like a virtualenv): /home/ob/oss/tox-dev/tox-direct/.tox/pypy

the folder looks fine though:

tree -L 2 .tox/pypy
.tox/pypy
├── bin
│   ├── activate
│   ├── activate.csh
│   ├── activate.fish
│   ├── activate.ps1
│   ├── activate_this.py
│   ├── easy_install
│   ├── easy_install-2.7
│   ├── libpypy-c.so -> /opt/pypy/bin/libpypy-c.so
│   ├── pip
│   ├── pip2
│   ├── pip2.7
│   ├── py.test
│   ├── pypy
│   ├── pytest
│   ├── python -> pypy
│   ├── python-config
│   ├── python2 -> pypy
│   ├── python2.7 -> pypy
│   ├── tox
│   ├── tox-quickstart
│   ├── virtualenv
│   └── wheel
├── include -> /opt/pypy/include
├── lib-python
│   └── 2.7
├── lib_pypy
│   └── readline.py -> /opt/pypy/lib_pypy/readline.py
├── log
│   ├── pypy-0.log
│   ├── pypy-1.log
│   ├── pypy-2.log
│   ├── pypy-3.log
│   ├── pypy-4.log
│   ├── pypy-5.log
│   └── pypy-6.log
├── site-packages
│   ├── _pytest
│   ├── [...]
│   └── zipp.pyc
└── tmp

[obestwalter]

It fails because of dir_items > {"bin", "lib"} - pypy does have lib_python and lib-python but no lib. We could now start checking for that, but I wonder if we can get away with something simpler and more generic as the main thing that needs to exist is bin/python to "qualify" as a venv.

Alternatively we can check for include rather than lib as this seems to be in all installations. I'll dig out pyenv though and check.

[obestwalter]

jython does not have an include (I know, we don't really actively support it anymore), but we don't have to actively prevent support either. So I went with adding and explicit check for the pypy layout.

[gaborbernat]

The only guarantee is that under bin dir there will be a python, we should check against that.

[obestwalter]

I went with going along how @asottile started. It's a bit safer as it looks at more and now with the addition of the pypy special case should work for all supported interpreters.