Command line parsing error with Python 3.8

[thorstenkampe]

• a detailed description of the bug or suggestion
  Command line parsing error with Python 3.8 when concatenating short options
• pytest and operating system versions
  Pytest 5.0.0, Python 3.8.0b1, Windows 10
• minimal example if possible

> pytest -vx
ERROR: usage: pytest [options] [file_or_dir] [file_or_dir] [...]
pytest: error: unrecognized arguments: -vx
  inifile: None
  rootdir: F:\Documents\Scripts\Runscript

pytest -v -x works

[nicoddemus]

Hmmm indeed we only apply a workaround for that Python bug in Python < 3.8:

pytest/src/_pytest/config/argparsing.py

Line 361 in 4bc0415

if sys.version_info[:2] < (3, 8): # pragma: no cover

@Zac-HD any thoughts? Perhaps we should use < 3.9 until the patch lands and a new 3.8 gets released?

[Zac-HD]

Sure - we should probably drop in an assertion that we're running on Python < 3.9 too, with a message that will remind us what to follow up on if it's slipped until then 😄

[nicoddemus]

Do you have some time to get to this later @Zac-HD? If you don't I can pick it up later in the weekend.

[Zac-HD]

Probably not sorry - family commitments all Sunday and a lot of writing I'm already behind on...

[nicoddemus]

No worries, thanks!