WIP: Adding cycling indent *NOT READY FOR MERGE*

[jackcviers]

• Functionality conceptually complete (haven't tested it yet)
• Trying to figure out how to test this with ERT before I QA it.

[jackcviers]

Ok. So I've been looking at how haskell-tng.el did their indentation tests, how scalafmt does its indentation tests, and so on. I have an idea for creating a set of indentation tests for this repo based upon the ideas there, but it's probably overkill for my toggle, and probably needs to be a separate pr for this package.

I will get some ert tests that use a demo scala buffer by tomorrow afternoon, then hopefully we can discuss this with the finished poc.

[jackcviers]

@Kazark So I have it cycling between 0 and current-indent when the custom scala-indent:use-cycle-indent is t. Can I get another set of eyes on it?

[jackcviers]

I haven't added tests, but I have verified it at several indent levels. One thing that's weird for me is that <TAB> is saying:

call-interactively@ido-cr+-record-current-command: Wrong type argument: commandp, t

and debug-on-error isn't giving me a backtrace. I don't think I touched that, so not sure what's going on here.

[Kazark]

@jackcviers Hey sorry for the no-show here. I lost momentum on my Scala 3 work because this is a blocker for me. I will try to take a look at this soon though and at least merge it into my branch.

[Kazark]

This change very much looks additive to me. I can't see how it can break my stuff, and it looks well done as far as I can tell. Thank you. I will merge it into my branch. Feel free to send follow-up PRs.

I definitely have some bugs still on my branch that need to be worked out.

[jj1uzh]

Wrong type argument: commandp, t error occurs here

emacs-scala-mode/scala-mode-indent.el

Lines 995 to 997 in 35f265f

	(if scala-indent:use-cycle-indent
	(call-interactively t 'scala-indent:cycle-indent-line)
	(call-interactively t 'scala-indent:strategy-indent-line)))