Delete is broken

[Daeron]

When deleting ways (or possibly combining two ways), they are not always removed from relations thus breaking uploading.

[Gubaer]

Can you post the error message you get on uploading? Is it a 412 Precondition Violation?

Perhaps the ways are part of relations which are not loaded into the local dataset. JOSM tells you what relation is involved in the Precondition Violation. Can you check (search for the id in your local dataset) whether it locally available?

If it isn't, this isn't a defect.

[jttt]

Maybe this is related to #4006. If referrers get broken than QuadBuckets for ways is no longer updated (#4006) and deleting can miss some referrers (#4001).

[Daeron]

Replying to Gubaer:

Can you post the error message you get on uploading? Is it a 412 Precondition Violation?

Perhaps the ways are part of relations which are not loaded into the local dataset. JOSM tells you what relation is involved in the Precondition Violation. Can you check (search for the id in your local dataset) whether it locally available?

If it isn't, this isn't a defect.

Yes, I got a 412, and yes, the relation was in the local dataset (downloaded at the same time as the way). The relation editor showed the way as having zero nodes, ie. deleted. I manually deleted the way from the relation and then the upload completed successfully.

[stoecker]

Zero nodes does not mean deleted. The node count has nothing to do with the deletion state. Could you make this situation reproducable?

[Daeron]

Okay, found a way to reproduce.

When you have a two-node way as a member of a relation, and the way is deleted by deleting the only segment (shift delete), it's not removed from the relations, thus leading to precondition violation when uploading (It tries to delete the way, but it's still a member of relation(s)).

So, this is pretty much the same as #3704, although leading to more severe problems.

[Daeron]

Closed as duplicate of #3704.