Slate: Applying changes without editor focus clobbers undo history

[quicksnap]

Do you want to request a _feature_ or report a _bug_?

Bug

What's the current behavior?

Replicated on https://www.slatejs.org/#/rich-text with latest Chrome browser.

When applying changes to a selection when the editor doesn't have focus, the undo history is clobbered.

To replicate:

1. Select some text.
2. Click outside the editor
3. Click on "Bold" toolbar mark
4. Click on editor and try to undo. It won't work.

Further, if you make changes and then try to undo beyond this invalid undo point, the user may no longer redo. This may be a separate issue.

What's the expected behavior?

Undo history should be retained.

[quicksnap]

In my local environment I was unsure of how to debug this. Through trial and error I figured out this was the root issue.

Any tips on inspecting why operations fail to undo/redo? I tried logging slate:operation*, but there is a lot of noise, ~and console-logged Immutable objects are tough to inspect =(~ (Edit: Just read about Immutable format extension.)

[Slapbox]

@quicksnap this PR fixes _some_ of the issues with history, but probably introduces more issues. It's also outdated now, slightly. You'd need to integrate the new changes to the on-history.js file (very minimal.)

If you want to work on improving this, I'd be happy to help. The trouble is that I got it nearly working just in time to step away for a few days, and when I came back, nothing made sense to me anymore. So it moves us closer, but good luck figuring out how =/

PS (I believe it fixes the specific issue you're seeing, but I can't recall with certainty)

[quicksnap]

@Slapbox which PR?

[Slapbox]

Ah crap, sorry about that. Here you go: https://github.com/ianstormtaylor/slate/pull/2347

The Master Branch version of that file includes two uses of withoutNormalizing that that PR doesn't include. I believe those are the only changes between that PR and the Master Branch.

[Slapbox]

By the way, there's a related issue here which might be of interest to you, though it has no solutions itself: https://github.com/ianstormtaylor/slate/issues/2098

[quicksnap]

Once the problem becomes more of a priority for me, I would be interested in helping. For now, I believe one workaround would be to prevent toolbars from modifying the document without a focused selection. So, one could destroy the selection editor.onBlur and also cause a editor.focus event before any toolbar actions occur.

This is a problem, though, and I would like to know how better to debug what's going wrong. There's a lot of events happening at any given moment, so it's difficult to diagnose what's going wrong with the history.

[Slapbox]

If I recall, when the editor is blurred, that creates a change in the history stack. I remember that clears all redos. I don't remember it clearing undos.

The way to troubleshoot this is to swap in some of the code from the undo/redo example and paste it into the rich text example so you can observe the history stack in relation to applied marks and your actions.

@ianstormtaylor would you be willing to accept a PR to add rich text to the undo example to make this easier for more people to observe/troubleshoot? I know it makes the example less pure in focus, but I think it could help get more eyeballs on perfecting the undo/redo stack logic.

[ianstormtaylor]

I believe that this may be fixed by https://github.com/ianstormtaylor/slate/pull/3093, which has changed a lot of the logic in Slate and slate-react especially. I'm going to close this out, but as always, feel free to open a new issue if it persists for you. Thanks for understanding.