[pypy-issue] Issue #3050: subprocess.Popen only accepts sequences (pypy/pypy)

[Markus Unterwaditzer]

New issue 3050: subprocess.Popen only accepts sequences
https://bitbucket.org/pypy/pypy/issues/3050/subprocesspopen-only-accepts-sequences

Markus Unterwaditzer:

This works in CPython \(it prints something\) but does not work in PyPy:

```python
from subprocess import check_output

print(check_output(iter("echo hello world".split())))
```

The Python docs say that subprocess requires `args` to be a sequence, so this program is buggy already. However, since pypy mostly attempts to be bug-compatible to CPython \(or at least sometimes does\), I figured it’d be worth reporting here.

Tested with CPython2/3 and pypy2/3:

* `[PyPy 6.0.0 with GCC 4.2.1 Compatible Apple LLVM 9.1.0 (clang-902.0.39.1)]`
* CPython 2.7 and 3.7