Wrong PointMouseHandler type on event handlers like onMouseMove

[madebyfabian]

Describe/explain the bug
When using event handlers like onMouseMove, onMouseEnter and so on with for example the <ResponsiveLine>, the return type of the callback parameters is (point: Point, event: React.MouseEvent) => void in TypeScript. But these types are wrong, since in runtime, the actual type you get is (slice: Slice, event: React.MouseEvent) => void. So instead of getting just one point, you get the whole slice object, including the points: Point[] array.

Not sure if it's only for the line chart or others also.

To Reproduce
Steps to reproduce the behavior:

1. Use [email protected]
2. Create a <ResponsiveLine data={...} onMouseMove={(...params) => { console.log(params) }} />
3. See the type mismatch in your editor versus the console logs real values

Expected behavior
Types match

[madebyfabian]

I also discovered that onTouchMove always returns the same slice, no matter where the finger is touching the chart. onMouseMove works perfectly fine and returns the exact slice the user hovers over. Is this by design?

nivo/packages/line/src/SlicesItem.js

Lines 64 to 89 in 839ff6d

	const handeOnTouchMove = useCallback(
	event => {
	// This event will be locked to the element that was touched originally
	// We find the element that is currently being "hovered over" by getting the element at the touch point
	const touchPoint = event.touches[0]
	const touchingElement = document.elementFromPoint(
	touchPoint.clientX,
	touchPoint.clientY
	)
	// Is this a nivo ref?
	const touchingSliceId = touchingElement?.getAttribute('data-ref')
	if (touchingSliceId) {
	// Is this a slice for this graph?
	const slice = slices.find(slice => slice.id === touchingSliceId)
	if (slice) {
	showTooltipFromEvent(createElement(tooltip, { slice, axis }), event, 'right')
	setCurrent(slice)
	}
	}
	// Note here, this will pass the original slice, not the one we found
	// But this can be found with document.elementFromPoint()
	onTouchMove && onTouchMove(slice, event)
	},
	[axis, onTouchMove, setCurrent, showTooltipFromEvent, slice, slices, tooltip]
	)

And is there a better way to get the current slice/points that is being hovered/touched over?

Not sure if this could be related with the type mismatch, if not, I can open a seperate issue.