[Maybe Fixed] Difficulty with using trucks in unusual situation TWW-related

zlefin

I think this is an engine bug, rather than being something in TWW code TWW_movebug.tsvg](/assets/uploads/files/1563141832074-tww_movebug.tsvg)

I want to move one AA from Moscow to Smolensk in the enclosed save; and am trying to do so via truck.

To help demonstrate clearly, start by selecting undo all, to cancel all the moves so as to start from a clearer point.
Move one truck from stalingrad to Moscow
Now select one truck and one aa gun to move to smolensk.

When ever I try to select them both and to the move, it asks me which Trucks to use, since some of the trucks have different amounts of movement remaining. Once I select the trucks to use, and click ok, only the truck ends up moved, the aa gun isn't moved at all. No matter which trucks I say to use, the aa gets deselected. So I couldn't get the aa to move.
Now if instead, I send trucks out of moscow, one by one, until all remaining trucks in moscow have the same amount of unused movement, and then try to move the AA with one of them, it works correctly.

A similar issue occurs with trains.
It seems like the issue is this: when trying to move units via trucks (And the associated mech-inf based land transport rules), if there are multiple land units in the same location with differing amounts of movement, then the menu for selecting which units to move comes up.
However when the menu is brought up, something "loses" the set of units that are supposed to be transported along with those units, and there's no way for it to reacquire/reselect those units. So they can't get transported in that situation.

It wouldn't matter for regular units, which are incapable of land transporting, so this issue should only occur in quite narrow situations.

ubernaut

@zlefin sounds kinda similar to this one, at least to me:

https://forums.triplea-game.org/topic/1246/unloading-bug

redrum

@zlefin Yeah, I've seen this happen as well. Work around is just move all the other trucks/trains out of the territory, make the land transport you want, and then undo moving all the other ones out.

@ubernaut Its similar to that. Though I believe that issue is fixed in the pre-release (if you want to test to confirm that would be very helpful).