"Bombing Raids should be dealt with first!" error with fast ai

[asvitkine]

Reproduction Steps

1. Open the save game from: Error with "canNotTarget" #11617 (comment)

Attach a Save Game

See: #11617 (comment)

Engine Version

Engine Version:
2.6 ToT

Is there anything else we should know?

[asvitkine]

So there is a bombing battle pending, but it has no attackers specified.
So it doesn't get handled when bombing battles normally get handled.
But then when the code goes to check for its presence, its still found.

Probably a fast AI bug causing it to create an empty battle.

[asvitkine]

OK, it's not quite that!

It seems if you send a unit to do a bombing raid, but it has movement left, you can still within the same combat move move it again, out of there, which could cause the battle to become "empty" (no attackers). So that's what's apparently happening in that AI game - probably the fast AI chooses for whatever reason to move that bomber out, which then creates this issue, where later code still think there's a battle, but was skipped due to being empty.

I think the simple fix is to check that the battle is not empty before throwing that error. (More complicated options can be pursued, for example by preventing further movement by that unit if it was committed to a bombing run - except to cancel the move or the move-back after in non-combat. But I won't do that for now.)