Some of you might have heard of the mythical tox4, some even feared that it will never happen. While a first public release is still months away, it got to a point where I’m happy for some brave few to give it a try. It’s available to install from here: https://pypi.org/project/tox/4.0.0a2.
If you can spare a few minutes, try it and let me know how it goes, that would be much appreciated. At the moment I’m mostly interested in things that work with tox 3 but breaks with tox 4. While it becomes stable it installs under the tox4 console entry and uses the tox4 working directory (not to break v3). This is a complete rewrite of tox 3, with python3.6+ only and lots of performance and feature improvements. However, for now, it’s more important to find things that broke so let’s focus on that. Until it becomes stable the name is tox4 (and similarly works in .tox4 work directory), so you can try it/use it in parallel with tox 3.
Just to state the obvious, this breaks completely all existing plugins by design. And also has a few breaking changes: e.g. use isolated builds by default. But comes with some benefits too: should be faster, more correct, and has full package dependencies and requirements.txt support (aka if you add a new dep either for your package or within the requirements.txt) tox will identify the addition and auto-install just what has been added if it’s new dependencies; or if you remove stuff it recreates the env from scratch (at some later point we can implement figuring out what to remove when you remove deps, to avoid the need to recreate). We no longer build the entire config world at startup (subprocess calls), but lazily load all configs, so we only manifest options if we must. For example, if you don’t use env_site_package_dir we don’t call a subprocess during the config phase to calculate that.
We no longer build the entire config world at startup (subprocess calls), but lazily load all configs, so we only manifest options if we must. For example, if you don’t use env_site_package_dir we don’t call a subprocess during the config phase to calculate that.
Also, tox now has subcommand:
tox4 --help run (r) run environments run-parallel (p) run environments in parallel depends (de) visualize tox environment dependencies list (l) list environments devenv (d) sets up a development environment at ENVDIR based on the env's tox configuration specified config (c) show tox configuration quickstart (q) Command-line script to quickly tox config file for a Python project legacy (le) legacy entry-point command
if you don’t specify anything legacy is implied.