fix(brightness): guard against null screen reference during disconnect - #193
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fix(brightness): guard against null screen reference during disconnect#193xdvi wants to merge 2 commits into
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The optional-chaining guard stops the TypeError flood, but doesn't address why it happened: monitors was a binding that recreated a BrightnessMonitor for every screen on each Quickshell.screens change, leaking the previous set (never destroyed, still parented to root, Timers/Behaviors still running) since none of them get destroy()ed. Each subsequent screen change added more zombies reacting to a dead screen reference, which is what actually drove CPU/memory up. Reconcile against the live screen list instead: reuse existing monitors for screens that are still connected, and destroy() the ones whose screen went away.
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Summary
This PR fixes a bug where disconnecting a monitor (e.g., when the screens are powered off by
swayidleduring idle) causes a flood ofTypeError: Cannot read property 'model' of nullwarnings inBrightness.qml, leading to 100% CPU usage, memory leaks, and processes being killed by the OOM killer.By adding optional chaining (
screen?.model), we safely handle cases where the screen reference becomes null during destruction.Root cause and the actual leak
The optional chaining stops the crash, but not the leak itself.
monitorswas a binding that recreated aBrightnessMonitorfor every screen on everyQuickshell.screenschange — the previous set of monitor objects was never destroyed (no.destroy()), just orphaned while still parented toroot, with theirTimer/Behavior/Processstill alive. Each screen connect/disconnect added another batch of zombie objects reacting to a deadscreenreference, which is what actually drove CPU and memory up over time, not a single error.Fixed by reconciling
monitorsagainst the live screen list instead of rebuilding it from scratch: screens that are still connected keep their existingBrightnessMonitor, and monitors whose screen went away are explicitlydestroy()ed.Testing
inir restart && inir logs— no errorsniri msg outputsthat the screen list actually changed, not just DPMSTypeError/ReferenceErrorduring or after the disconnect/reconnect cycleqt.qml.listvalueconversionwarning appears in both versions, confirming it's a pre-existing Quickshell/Qt quirk unrelated to this change, not a regression