Crash when switching off bluetooth while scan is ongoing

[dev-pac]

Version: from 1.7.0 (not tested earlier)

Steps to reproduce:

• Launch a scan
• on your device go to the settings to switch off bluetooth

result:

Thread 5: Fatal error: SWIFT TASK CONTINUATION MISUSE: scanForPeripherals(withServices:options:) tried to resume its continuation more than once, throwing operationCancelled!

in CentralManaager().scanForPeripherals(...) in the catch block, line 87

expected:

• scan is "paused"

[dev-pac]

Modification: working correctly in 1.4.1

[manolofdez]

Aha! I know why this is happening!! scanForPeripherals will resume with an async stream, but the enqueue call stays awaiting until the stream completes. Turning off Bluetooth does not terminate the stream. So you're probably calling cancelAllOperations when the bluetooth is turned off, which tries to send an operationCancelled to the enqueued operations. But since the scanForPeripherals continuation has already been used, the app crashes.

I'm going to want to re-think the strategy here, but I have a quick workaround for this. Stay tuned....

[dev-pac]

Cool; thanks