Formatting breaks undo, sometimes

[jscheid]

Hi, I'm surprised this hasn't been reported before, so maybe this is a misconfiguration... but is it possible that formatting breaks undo? I have rust-format-on-save enabled and quite often, after saving, either undo does nothing or I get a message saying that the end of undo history has been reached, when clearly there were previous edits. I haven't figured out a pattern yet, but this only appears to happen sometimes.

Obviously, undo can't work in the newly formatted buffer (by which I mean, an edit can't be undone while preserving the new format) but it should be possible to undo the formatting itself (and then any previous edits); this is, for example, how prettier-emacs works.

[mookid]

hi @jscheid,

Thanks for the report. I saw that indeed happen as well.
Are you using the undo-tree package?