>  1. cargo new --vcs git foo
>  2. echo 'mod foo;' >> foo/src/main.rs
>  3. emacs -Q foo/src/foo.rs
>     (foo.rs DOES NOT EXIST YET -- that is part of the bug)
>  4. M-x rust-ts-mode RET
>  5. (progn (setq track-changes-record-errors 'trace) (setq debug-on-error t))
>  6. C-x C-f main.rs RET
>  7. M-x eglot RET
>  8. echo 'struct foo;' > foo/src/foo.rs
>  9. C-x C-f foo.rs RET
> 10. yes RET

Thanks, I managed to reproduce it locally with:

    rm foo.c
    emacs -Q foo.c -f eglot
    echo 'struct foo;' > foo.c
    M-x revert-buffer RET

and that pointed to a bug in `track-changes.el` which could explain the
problem you reported originally.

So, I pushed the patch below to `emacs-30`.

It seems part of the problem also comes from `insert-file-contents`
which apparently fails to run the `before-change-functions` in the above
recipe, but I haven't investigated this any further yet, and
track-changes *should* tolerate this (potentially emitting a warning
along the way), and with the patch, the above recipe now works for me
without error nor warning.


        Stefan