implement support for PEP-518 - the tool.pytest key in pyproject.toml

[RonnyPfannschmidt]

as per https://www.python.org/dev/peps/pep-0518/#specification

the file has a section for tools using the pypi name for the tool,

so this is the one file where we can properly and in a supported way put metadata

i propose adding support asap and deprecating the other config files for the 3.x series so we can possibly remove support starting with the 4.x series

[The-Compiler]

Big -1 on deprecating pytest.ini if you also suggest that.

My config files are pretty big, which is why I want to keep them in their own file rather than stuffing everything into one - line count:

   18 .coveragerc
   59 .flake8
   13 .pydocstylerc
   69 .pylintrc
  245 tox.ini
   41 pytest.ini

[RonnyPfannschmidt]

i see, good point!

i change my proposal to deprecating all files other than pytest.ini and pyproject.toml

[hynek]

Any plans on moving this forward? 😇

[RonnyPfannschmidt]

@hynek yes, but no time/volunteer

[tadeoos]

Hey guys, I gave it a go in #3686. It adds support for pyproject.toml but doesn't deprecate anything.