How to best handle ISO-8859-1 encoded files

[alex-aua]

We have a certain type of files in our repository (Java .properties files) that have to be ISO-8859-1 encoded.

A colleague of mine was confused by git diff showing seemingly broken characters. Now, I'd like to fix that in .gitattributes by adding the following line:
*.properties text eol=lf working-tree-encoding=ISO-8859-1

However, that leads (as far as I understand) to git converting all these files to UTF-8 in the index.

This, in turn, leads to jj checking them out incorrectly (that is: UTF-8), or in case of a collocated repo, marks everything dirty.

That would mean that I would have to stop using jj for that repository, wouldn't it? The line-ending conversion workaround (yeah, it's Windows on top of everything) wouldn't work #6493 here. Maybe, though, I am missing another approach/workaround.

Not sure if this would have been better added to an issue, it's related to #6762 and #53. I don't want to spam there before getting at least some feedback as to how/where I should report.

[yuja]

Unfortunately, I don't think there are better workarounds for this problem. Maybe you can add temporary commit containing the "reverted" *.properties files, but it might be tedious to work.

https://jj-vcs.github.io/jj/latest/FAQ/#how-can-i-avoid-committing-my-local-only-changes-to-tracked-files

If we add support for negative sparse patterns, *.properties file could be excluded from the jj's checkout, and can be managed by git.

#1896

FWIW, I personally believe that content rewriting by VCS is misfeature, and I don't think we'll add native support for that unless there are large user base who are affected by the problem (such as the default CRLF translation of Windows Git.)

[joyously]

FWIW, I personally believe that content rewriting by VCS is misfeature, and I don't think we'll add native support for that

I agree with this, but I see jj fix as the VCS rewriting content also.

[alex-aua]

I tend to agree. I'd have much preferred if git would have left the index alone.

All I needed/need is a way to tell git / jj to interpret the files correctly. That is: configure the encoding for when they already read/write these files, so that they present the correct diff. Is there already an issue/documentation for something like this?

Thanks for pointing me to the negative sparse patterns, I'll track that issue and hope that it helps generally with migration while git/jj are used simultaneously.

[yuja]

There isn't mechanism for diff pre-processing at least in jj. For now, you'll have to use external diff command.
https://jj-vcs.github.io/jj/latest/config/#generating-diffs-by-external-command