🐞 Fix crash when a cycle action has an empty cycle - #1115
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mrkai77
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Jul 2, 2026
`getNextCycleAction` indexes `currentCycle[0]` when restarting or when no current index is found, but only guarded against a nil `cycle`, not an empty one. A cycle action configured with zero sub-actions therefore traps (EXC_BREAKPOINT) on the empty-array subscript. Guard against an empty cycle and return the action unchanged.
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mrkai77
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Swiftformat errors are unrelated to this PR; merging! Thanks! |
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Summary
A cycle action configured with an empty cycle list crashes Loop with
EXC_BREAKPOINT(SIGTRAP) — an out-of-bounds array access.Root cause
LoopManager.getNextCycleActionguardsaction.cycleagainstnilbut not against an empty array, then doescurrentCycle[0]on the cycle-restart path and the "no current index" fallback. An empty cycle →currentCycle[0]traps.Crash (abridged):
EXC_BREAKPOINTinLoopManager.getNextCycleAction→changeAction→openLoop.Fix
Guard against an empty cycle too, returning the action unchanged (there's nothing to advance to).
Testing
Built (Release). A cycle action with zero sub-actions no longer crashes; non-empty cycles are unaffected — the guard only changes the empty case.