I’m a little confused about road name changes. If there is no junction it’s simple - you have two connected roads, each with different names, they connect at the point the name changes.
The problem is if there is e.g. a T-junction at the point of the name change. Then it’s not clear in the map that two of these form a single road, with the third one having to give way on entry. So if someone was travelling down the road, passing the T-junction, a sat nav system might say ‘turn left’ here, when the person doesn’t need to turn at all! Not a disaster, but not ideal.
An obvious work around is to put the name change as a separate node just after the T-junction, but there’s probably a better way of doing it.
AFAIK, there is no way to express how the main road (e.g. same reference number) continues after a junction. At this moment, we assume that the makers of the navigation app solve this problem.
I remember seeing a proposal a long time ago that would help to solve this problem. It was some relation that expressed how the road continues (and it was not https://wiki.openstreetmap.org/wiki/Relation:connectivity))
Yes! type=through_route is exactly what I’m talking about. Disappointing that it’s not implemented, and that (I assume) no equivalent thing was added to the junction relation.
For an example: https://www.openstreetmap.org/#map=19/51.13097/-4.21998 the two tertiary roads (georgeham road and st mary’s road) are actually one continuous road, with the residential road (st mary’s road) joins the tertiary road at a T-junction. This is not clear from the OSM data.
and here’s an example that used to be the same issue, but I’ve recently added a workaround. https://www.openstreetmap.org/#map=18/51.46325/-1.03935 as you can see, the southern arm of armour road is the same road as lower armour road, but this wasn’t clear prior to my recent edit.