Fix compatibility with tox>=4

[ZenulAbidin]

This commit introduces compatibility with Tox version 4 by making the following changes:

• The deleted _split_envs function is surgically pasted from old Tox code to v4_workarounds.
• The hooks are now defined using the @impl decorator and not @tox.hookimpl.
• The addoption hook is renamed to add_option, while the configure hook is switched to tox_env_config (I wasn't 100% sure doing this, but it seems to make tox4 run successfully, so let me know if there is a more correct way to port it.)

If you need Tox4 support immediately and can't wait for this to get merged, put this in your requirements.txt:

tox-travis @ git+https://github.com/ZenulAbidin/tox-travis@b07180da9508e9a6de3fa516f6fcc95f4e85759f

I have not been able to test this live on Travis CI, because builds have been completely broken for me since recently and customer support is non-responsive.

[ryanhiebert]

Makes sense to me, but I similarly cannot test it or debug it.

[ZenulAbidin]

@ryanhiebert I can make a mock project using cookiecutter-pypackage, which features tox-travis integration, and then attempt to link it to a new Travis CI account and hopefully I'll be able to see if the changes work properly.

[ZenulAbidin]

So I have some good news, after making a new travis account with a boilerplate cookiecutter project, which includes my build of tox-travis, the (Gitlab) project has successfully built on Travis CI, and tox tests completed successfully. Results are here: https://app.travis-ci.com/gitlab/ZenulAbidin/Ragnarok

Ideally let's get this merged before my Travis trial credit expires again :)

[ZenulAbidin]

@ryanhiebert any update on this?

[ryanhiebert]

Do we know when this was added to tox? Do we need to restrict the lower bound?

[gaborbernat]

Likely you should restrict to latest release, because that's also against what you're running the CI.

[ZenulAbidin]

See my comment below - this is not compatible with tox<4.

[ZenulAbidin]

Are we talking about restricting the `tox` version at requirements.txt, or somewhere else?

…

On Mon, May 15, 2023 at 8:47 PM, Bernát Gábor ***@***.***> wrote: @gaborbernat commented on this pull request. --------------------------------------------------------------- In [src/tox_travis/hooks.py](#163 (comment)): > @@ -15,8 +16,8 @@ from .after import travis_after ***@***.*** -def tox_addoption(parser): ***@***.*** +def tox_add_option(parser): Likely you should restrict to latest release, because that's also against what you're running the CI. — Reply to this email directly, [view it on GitHub](#163 (comment)), or [unsubscribe](https://github.com/notifications/unsubscribe-auth/AKE46J73XOZKMBLYOIMWFCDXGJT4BANCNFSM6AAAAAAX6AE6NM). You are receiving this because you authored the thread.Message ID: ***@***.***>

[ryanhiebert]

Are we talking about restricting the tox version at requirements.txt, or somewhere else?

In the setup.py is what I was referring to, which constrains people from using tox-travis with a lower version of tox, for example if the hooks we're starting to use here were only introduced in a later version of tox.

[ZenulAbidin]

@ryanhiebert

The change appears to have kicked in starting from tox-dev/tox#1991 (Changed Files), which was packaged in version 4.0.0a7.

Looks like it really is tox>=4-only material.

Also there is this thing at the bottom of the Changelog page of Tox:

Warning

The current tox is the second iteration of implementation. From version 0.5 all the way to 3.X we numbered the first iteration. Version 4.0.0a1 is a complete rewrite of the package, and as such this release history starts from there. The old changelog is still available in the legacy branch documentation.

Perhaps we should make a branch of the existing codebase with a name like tox-v3 or something that is only for older tox versions.