Merging two nodes does not preserve the longest history

[pangoSE]

Hi
Merging two nodes does not always preserve the longest history.
Is it possible to implement this?

Cheers

[stoecker]

As far as I remember it preserves the history of the oldest node (i.e. lower id).

[Don-vip]

Yes:

    /**
     * Find which node to merge into (i.e. which one will be left)
     *
     * @param candidates the collection of candidate nodes
     * @return the selected target node
     */
    public static Node selectTargetNode(Collection<Node> candidates) {
        Node oldestNode = null;
        Node targetNode = null;
        Node lastNode = null;
        for (Node n : candidates) {
            if (!n.isNew()) {
                // Among existing nodes, try to keep the oldest used one
                if (!n.getReferrers().isEmpty()) {
                    if (targetNode == null || n.getId() < targetNode.getId()) {
                        targetNode = n;
                    }
                } else if (oldestNode == null || n.getId() < oldestNode.getId()) {
                    oldestNode = n;
                }
            }
            lastNode = n;
        }
        return Optional.ofNullable(targetNode).orElse(oldestNode != null ? oldestNode : lastNode);
    }

[pangoSE]

Perfect.
When I edit and merge nodes I would like JOSM to specify in the changeset in some way that the deleted nodes stem from merging nodes.
Is that possible?
It seems that changesets can have tags when looking at ​https://www.openstreetmap.org/changeset/63276307

Maybe the changeset tags:
deleted_nodes_from_merging = yes
deleted_nodes_from_merging:procent = 100

or something like that would be suitable.

That way I and tools can easier destinguish edits with a lot of deleted nodes that is not a result of merges.