fix: Duplicated add combatant lines from concurrent state checks#534
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valarnin
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May 7, 2026
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In extremely rare cases,
LineCombatantcan emit duplicateAddlines for the same combatant within a short time window. In my logs, this occurred in less than 0.1% of single-mechanic captures (e.g. the Loop towers in TOP P1), but it can still break triggers that wait for data from the first nEventObjectentries before continuing.Example log:
This appears to be caused by a race condition where multiple checks can observe the same combatant as missing before one of them adds it to the state map. This change makes the add path use
TryAdd.Since the issue is extremely rare, I cannot confirm that it is actually fixed, but it addresses the race condition I was able to identify.