Function getChild

src/utils.js:319–340

* Gets nth child of el, ignoring hidden children, sortable's elements (does not ignore clone if it's visible) * and non-draggable elements * @param {HTMLElement} el The parent element * @param {Number} childNum The index of the child * @param {Object} options Parent Sortable'

(el, childNum, options, includeDragEl)

 * @return {HTMLElement}          The child at index childNum, or null if not found
 */
function getChild(el, childNum, options, includeDragEl) {
	let currentChild = 0,
		i = 0,
		children = el.children;

	while (i < children.length) {
		if (
			children[i].style.display !== 'none' &&
			children[i] !== Sortable.ghost &&
			(includeDragEl || children[i] !== Sortable.dragged) &&
			closest(children[i], options.draggable, el, false)
		) {
			if (currentChild === childNum) {
				return children[i];
			}
			currentChild++;
		}

		i++;
	}
	return null;
}

/**
 * Gets the last child in the el, ignoring ghostEl or invisible elements (clones)