Python 3.7, 3.8 support, improved unittest support

[nanobowers]

This PR also contains some edits based on a fork from @fryguy - namely support for F-Strings.

Enhancements:

• Support for python 3.7 up to python 3.8.6 has been added. For some reason I am having trouble getting py3.9 to work at the moment, hope to revisit that later. (#6 per @ankane)
  • Integrated @fryguy f-string support (visit_JoinedStr, visit_FormattedValue) support for some fstring modifiers (e.g. {foo!r}) and added unit tests.
  • Added support for visit_Constant from 3.8+
• Added try/except in run_tests.py to pre-check existence of development package dependencies before failing (#5 @joel)
• Added support for many additional python unitTest --> ruby test/unit, and consolidated testing files somewhat.

[Fryguy]

I totally forgot I forked it with that fix 😆

[jayvdb]

ping @naitoh , could you review this. I would like to make other PRs, but it doesnt make sense to do that unless this is merged as I need py38+ support.

[nanobowers]

Hi @jayvdb, I am hopeful that @naitoh returns, but it appears he has been inactive for quite some time.

I have recently made some fixes to my repo that address some of the issues you filed:

• 8

• 11

• 12

• 13

• 11

• Plus os.environ/os.getenv support and some other fixes ...and put them on my master branch: https://github.com/nanobowers/py2rb/tree/master .

Please feel free to submit issues/PRs there if you wish.

Hopefully we can get clarification if this repo is abandoned and (if so) figure out if it can be handed off to someone else.

[jayvdb]

Great. There are now two main bugs found by the py2many test suite

• exceptions: https://github.com/naitoh/py2rb/issues/10
• comb_sort https://github.com/naitoh/py2rb/issues/15

And one that is not as critical

• byte_literals: https://github.com/naitoh/py2rb/issues/14

I think I saw that @naitoh was active on Twitter. Might want to catch him there or on email, to find out the future of this package.

[nanobowers]

I think I saw that @naitoh was active on Twitter. Might want to catch him there or on email, to find out the future of this package.

@jayvdb So far, attempts to reach @naitoh outside of GitHub have been unsuccessful. Not sure the best way to proceed is...