IPython 8.0 requires pre-release dependency

[pehala]

With the release of IPython 8.0 it is now dependent on black, which has all releases on pypi marked as pre-release, that means, e.g. you cannot install IPython 8.0 with pipenv without enabling pre-release dependencies even tho IPython is not pre-release.

[n1ngu]

Per the documentation I would still expect the black requirement to be optional

https://ipython.readthedocs.io/en/stable/whatsnew/version8.html#auto-formatting-with-black-in-the-cli

Not that this can happen after black is required in the setup.cfg after df3248f

I'd suggest to require black in an extras dependency in setup.py just as the parallel, kernel, qtconsole, notebook and whatnot features, so that one could enable the dependency by installing ipython[autoformat] or ipython[all] and so that people can opt out of the black requirement entirely!

Otherwise, I'd expect the docs to be updated. Actually, docs should be updated nonetheless!

This will be an easy patch I could work out, but I'd like a maintainer to share their concerns here as there is sort of a decision to be made against a very recent new decision to force the black requirement.

[n1ngu]

Rephrased: "enabled by default" != "forcefully enabled"

[lpsinger]

👍 black is not a runtime dependency of IPython, so it shouldn't be in install_requires. Black is only needed for development. It should be in extras.

[Carreau]

I didn't not realised that this will be a problem, I'll try to move it to optional dependency for next release.

[n1ngu]

For a possible workaround, explicitly state a black pre-release as a requirement in your Pipfile. This

[packages]
black = "==21.12b0"
ipython = "*"

installs just fine. (but it is cumbersome and hard to maintain, etc, so better wait for ipython 8.1)

Also, this does not affect recent pipenv versions so maybe update the very pipenv if you can afford it.

[pehala]

Also, this does not affect recent pipenv versions so maybe update the very pipenv if you can afford it.

Thank you! Newer pipenv worked wonders.

[renzon]

As a workafound I prefered seting Ipython to < 8:

ipython = "<8"

There is not good reason in sending black to production.

[n1ngu]

There is not good reason in sending black to production.

Sorry if this goes offtopic, but:

@renzon if you are deploying an application that relies on IPython, this is specifically a very good reason to send black alongside it! If you weren't already or even if IPython-8.1 won't have a hard requirement on black, I'd suggest to consider installing it to unlock extra IPython features for your application.

If your app does not use IPython in production... then you would have no reason to send IPython to production at all. Black is not the issue, so I'd suggest to sort out your production vs development requirements (pipenv install --dev ipython given that you are attending this issue)

[JelleZijlstra]

FYI we're planning to release a non-beta version of Black by the end of the month.

[Carreau]

Closing, black has been removed as hard dependency , and it's stable now.