Is your feature request related to a problem? Please describe.

I like to use delta as my diff formatter, because it simply looks nicer compared to the default diff formatter; it's syntax highlighting makes it much nicer to parse diffs.

At the same time, I also really like using difftastic for its syntax aware diffs, which other times makes parsing diffs even better compared to delta.

I use both quite equally in fact, that I have made jj show use delta, and I created an alias jj showd which uses difftastic!

Other times, I also like to use jj show -w or jj show -b, for example in cases where difftastic just simply fails.

Describe the solution you'd like

It would be great, if I can specify multiple preview commands in jjui that I can cycle through. That way, with a single keybind, I can quickly switch between - say - delta and difftastic, with or without -w and/or -b.

Describe alternatives you've considered

Currently, I am using the following config to achieve something that is close enough:

[preview]
file_command = [
    "--config",
    "ui.diff-formatter=difft",
    "diff",
    "--color",
    "always",
    "-r",
    "$change_id",
    "$file",
]
revision_command = [
    "--config",
    "ui.diff-formatter=delta",
    "show",
    "--color",
    "always",
    "-r",
    "$change_id",
]

Why current features fail to cover this request

While the above solution poses a valid workaround, it doesn't quite capture the experience of switching between previewers. As a matter of fact, I rarely look at diffs for individual files in jjui, so being able to cycle between multiple revision_commands would be a really neat QOL improvement. Same goes for file_command and all other kinds of [preview].

Furthermore, the above strictly limits me to 2 different previewers (with the added (yet small) overhead of having to navigate to the file based preview)

Additional context

None.