Reduce friction with ignored files by marking problematic files as conflicted

[Swire42]

Current situation

It seems that in the current state, jj's auto-tracking is somewhat hurtful whenever the set of ignored files changes.

Related:

• jj st may change repository state #8960
• Previously ignored files should not become tracked on checkout #5596
• working_copy: persist untracked file decisions in TreeState #8628
• Display newly tracked files #8317
• jj edit should fail if editing would cause currently ignored files to become tracked #7237

As far as I can tell, some "solutions" would go against jj's principles, such as "commands should avoid failing whenever possible".

Moreover, jj isn't super helpful at the moment when it comes to cleaning up after the facts (xargs -a .gitignore jj file untrack...)

Proposal

Would it make sense to mark files whose ignored status changes as conflicted?

(conflicted between existing or not, same kind as when merging a change to a file and a deletion of that same file)

Examples:

cd $(mktemp -d)
jj git init
jj new
echo foo > .gitignore
touch foo
jj edit @- # foo goes from ignored to non-ignored
jj status # Current: foo is tracked / Proposal: foo is conflicted

cd $(mktemp -d)
jj git init
touch foo
jj status # trigger snapshot (arguably it is suboptimal that snapshoting has side-effects)
echo foo > .gitignore # foo goes from non-ignored to ignored
jj status # Current: file is tracked / Proposal: file is conflicted

This is only partially thought-through, and the devil might be in the details, as I'm not entirely familiar with how conflicts interact with descendants.

While this doesn't directly solve the usability issue, it at least notifies the user that attention is needed.

Solving the usability issue would then require having ways to mass-resolve conflicts. I don't know if that's currently easy to achieve.

Would this fit jj's philosophy?