fix: replace the whole node in nodeInputRule

[ngryman]

Hi,

This PR fixes some issues with the horizontal rule:

• Horizontal rule by input rule adds extra paragraph node above #3809
• HorizontalRule extension: inconsistent behavior #1964
• Horizontal Rule adds empty line #1665

The new behavior creates a new paragraph below the horizontal rule, instead of above.

Implementation

I changed the implementation of nodeInputRule for the case when there's no group matched in the input rule regexp.

As far as I understand, the previous implementation was trying to replace the content of the existing node, not the node itself. We need to include the node boundaries as well to do so: start - 1 and end + 1.

The new implementation first inserts the new node at the existing node position (start - 1) and then delete the remaining content. Let me know if that makes sense or if there's a better approach.

Grepping the codebase quickly, it seems that other usages of nodeInputRule always use a matching group, so this change should only affect the HorizontalRule extension.

[chrisdeeming]

Anyone wishing to shim this to fix the HorizontalRule issue can use this extension:

const ExtHorizontalRule = HorizontalRule.extend({
	addInputRules() {
		return [
			new InputRule({
				find: /^(?:---|—-|___\s|\*\*\*\s)$/,
				handler: ({ state, range, match }) => {
					const attributes = {};

					const { tr } = state
					const start = range.from
					let end = range.to

					tr.insert(start - 1, this.type.create(attributes)).delete(
						tr.mapping.map(start),
						tr.mapping.map(end),
					);
				}
			})
		]
	}
});

[steven-tey]

@chrisdeeming you're a lifesaver – that worked! Thank you!

[rfgamaral]

FYI, Tiptap v2.1 was meant to fix this issue (there was some work done in that regard here), but I'm finding that the change on this PR works much better, more details in this comment.

[bdbch]

Thanks for letting me know about the patch @rfgamaral – I'll check the functionality of it and if it works fine replace my changes with it.

[bdbch]

I merged this fix with develop on this new PR here where your commit is included @ngryman:
#4341

I'll close this PR in favor for the new one