Delete all will fail when there are three blocks or more

EDIT: previously this was only an issue when the last block ended in a inline void node. Now it is always an issue.

Do you want to request a feature or report a bug?

Bug

What’s the current behavior?

If you have three blocks or more, where the last block ends with an inline void node, and you select everything and hit backspace (delete), it will fail with error:

Uncaught Error: `Node.assertNode` could not find node with path or key: List [ 1 ]

Reproduction:

1. Goto the emoji-example
2. Add an emoji at the end of the last block.
3. Select everything (command/ctrl-A)
4. Hit backspace

What’s the expected behavior?

That everything will be deleted without error.

I have noticed that when deleting all (and you have three or more blocks) the change will include an operation with type move_node where the path property is a block path (i.ie [2] with the same value as the newPath prop [2]. I think Slate will regenerate keys for this operation and it may lead to issues.

[skogsmaskin]

Pushed an update to the PR. Now for a go at nuking that move_node(X,X) operation. Thanks a lot @ericedem, @Slapbox and @ianstormtaylor! ❤️

[ericedem]

Ok I think I may have found the culprit, or at least something close. This bit of code: https://github.com/ianstormtaylor/slate/blob/master/packages/slate/src/commands/at-range.js#L228-L234

Which is why this is specifically failing with 3 or more blocks, because it is looking at the original start and end blocks which will never be next to each other. What happens in the case of 3 blocks is that move seems to be inadvertently adding or transforming one of the existing dirty paths to [ 2 ] (even though there isn’t a node at [ 2 ] at this point), which will eventually get changed to [ 1 ] by the merge (which both of these seem a little odd). Then when normalization happens [ 1 ] is invalid.