in public/src/js/models/group.js [68:89]
normalizeDropTarget(targetGroup) {
var isAfter, target;
// Dragging above a Group is like dragging above the last item in that group
// or if there aren't any other items, above those in the first preceding group that contains items.
isAfter = false;
target = _.last(targetGroup.items());
if (target) {
isAfter = true;
} else if (targetGroup.parentType === 'Collection') {
let groups = targetGroup.parent.groups;
for (var i = groups.indexOf(targetGroup) - 1; i >= 0; i -= 1) {
target = _.last(groups[i].items());
if (target) {
isAfter = true;
break;
}
}
}
return {isAfter, target};
}