Inconsistent behavior when merging nodes

[dforsi]

In the attached file you can find nodes that share the same position (it's real data from which I removed other nodes for clarity):

id='1747860328' lat='37.7230417' lon='14.0540179'
id='2465869552' lat='37.7230417' lon='14.0540179'

id='2465102612' lat='37.7230793' lon='14.0489794'
id='2465102614' lat='37.7230793' lon='14.0489794'

When fixing with the Validator, nodes 2465102614 and 2465869552 get deleted and node 2465102612 gets modified (with no reason because it has the same coordinates before and after the merge and there aren't tags on these nodes).

When merging manually with the "m" command, nodes 2465102614 and 2465869552 still get deleted but this time node 1747860328 gets modified (again with no reason I can see).

When merging with Ctrl+mouse drag, nodes 2465102614 and 2465869552 still get deleted and no other node is modified (it works the same no matter which node is dragged); this is the behavior I expect from the Validator.

I checked this with versions 6115 and 6269.

[dforsi]

Test data to check merge operation

[Don-vip]

In 6275/josm:

fix #9129 - unnecessary change command when merning two nodes with exact same coordinates

[Don-vip]

Thanks for this detailed description and precise test file. If all bug reports were like this :)

[stoecker]

Milestone renamed