Copy callback list before dispatching updates#44
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A registered callback may deregister callbacks while it runs — e.g. a Home Assistant entity tearing down during a push deregisters its own update callback. Iterating self._callbacks directly means that removal mutates the list mid-iteration and the loop skips the following callback, so some consumers can miss an update. Iterate over a snapshot (list(self._callbacks)) at both data-callback dispatch sites, matching how _set_connected already dispatches the connection-state callbacks.
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Jul 14, 2026
The call_soon deferral introduced an ordering hazard: when pynobo processes a buffered zone removal followed by an id-reusing add before the deferred removal runs, the re-add is rejected as a duplicate and the stale snapshot then deletes the surviving entity, leaving the zone with no entity until reload. Synchronous removal has no such window — the old device/entity is gone before the next buffered message's add. The original re-entrancy concern (mutating pynobo's callback list mid-dispatch) is harmless here (per-message dispatch; removal messages don't update survivors) and is fixed at the root upstream in echoromeo/pynobo#44.
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A registered callback may deregister callbacks while it runs — e.g. a Home Assistant entity tearing down during a push deregisters its own update callback. Iterating
self._callbacksdirectly means that removal mutates the list mid-iteration and the loop skips the following callback, so some consumers can miss an update.Iterate over a snapshot (
list(self._callbacks)) at both data-callback dispatch sites, matching how_set_connectedalready dispatches the connection-state callbacks.Triggered by this comment: home-assistant/core#176511 (comment)