Undoing pasting the same content with list multiple times throws error

[jodator]

Is this a bug report or feature request? (choose one)

🐞 Bug report

💻 Version of CKEditor

latest master @ Chrome

📋 Steps to reproduce

1. Select some content that contains a list
2. Paste it ctrl + v
3. Select all content ctrl + a and paste the content again ctrl + v
4. Place caret somewhere in the content and paste again ctrl + v
5. Undo
6. Undo

✅ Expected result

The undo is applied.

❎ Actual result

Error in the console.

📃 Other details that might be useful

Stack trace:

ckeditorerror.js:46 Uncaught CKEditorError: move-operation-nodes-do-not-exist: The nodes which should be moved do not exist. Read more: https://ckeditor.com/docs/ckeditor5/latest/framework/guides/support/error-codes.html#error-move-operation-nodes-do-not-exist


    at MoveOperation._validate (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:53117:10)
    at Model.on (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:50565:14)
    at Model.fire (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:109249:29)
    at Model.(anonymous function) [as applyOperation] (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:111194:16)
    at UndoCommand._undo (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:104349:11)
    at Object.editor.model.enqueueChange [as callback] (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:104636:9)
    at Model._runPendingChanges (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:51185:58)
    at Model.enqueueChange (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:50687:9)
    at UndoCommand.execute (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:104635:21)
    at UndoCommand.on (https://a2ee7d01.ngrok.io/ckeditor5/build/docs/ckeditor5/latest/snippets/features/ui-language/snippet.js:111190:32)

[scofalik]

I confirm the issue, it is still reproducible.

The steps can be streamlined:

0. Prepare empty sample.
1. Copy a list item (can be from the editor).
2. Paste the list item.
3. Paste the list item again inside the first one.
4. Undo, undo.

The same can be reproduced with headings, so it is not strictly related to lists. Probably some OT error. I am on it.

[scofalik]

I fixed the bug but when you redo, redo after the last step it still crashes, so I will take a look at that. Hopefully, I will find a solution in a reasonable time. If not, I will create a followup issue.

[Reinmar]

Does it crash due to ckeditor/ckeditor5-engine#1678 (comment)? Or maybe my TC will allow you to better understand the redo thing.