Fastlane snapshot warnings "Unable to mount DeveloperDiskImage"

Question

Whilst this does not prevent fastlane snapshot from working, I was wondering why I get the following warning (pictured in purple) when running?

[13:11:17]: ▸ 2018-01-23 13:11:17.281 xcodebuild[87131:11428054]  iPhoneSupport: Unable to mount DeveloperDiskImage on Jack’s Apple Watch (Error Domain=com.apple.dtdevicekit Code=-402653158 "The device is passcode protected." UserInfo={NSLocalizedDescription=The device is passcode protected., com.apple.dtdevicekit.stacktrace=(
[13:11:17]: ▸ 0   DTDeviceKitBase                     0x00000001148bffed DTDKCreateNSError + 113
[13:11:17]: ▸ 1   DTDeviceKitBase                     0x00000001148c0831 DTDK_AMDErrorToNSError + 1135
[13:11:17]: ▸ 2   DTDeviceKitBase                     0x0000000114901441 -[DTDKMobileDeviceToken mountDeveloperDiskImage:withError:] + 782
[13:11:17]: ▸ 3   DTDeviceKitBase                     0x0000000114901cf8 -[DTDKMobileDeviceToken mountDeveloperDiskImageWithError:] + 488
[13:11:17]: ▸ 4   IDEiOSSupportCore                   0x00000001147d65ae __28-[DVTiOSDevice attachToken:]_block_invoke_4 + 216
[13:11:17]: ▸ 5   DVTFoundation                       0x0000000108a75a4f __DVTDispatchAsync_block_invoke + 806
[13:11:17]: ▸ 6   libdispatch.dylib                   0x00007fff72b10591 _dispatch_call_block_and_release + 12
[13:11:17]: ▸ 7   libdispatch.dylib                   0x00007fff72b08d50 _dispatch_client_callout + 8
[13:11:17]: ▸ 8   libdispatch.dylib                   0x00007fff72b1be76 _dispatch_continuation_pop + 472
[13:11:17]: ▸ 9   libdispatch.dylib                   0x00007fff72b136cb _dispatch_async_redirect_invoke + 703
[13:11:17]: ▸ 10  libdispatch.dylib                   0x00007fff72b0a941 _dispatch_root_queue_drain + 515
[13:11:17]: ▸ 11  libdispatch.dylib                   0x00007fff72b0a6ed _dispatch_worker_thread3 + 101
[13:11:17]: ▸ 12  libsystem_pthread.dylib             0x00007fff72dcd1ca _pthread_wqthread + 1387
[13:11:17]: ▸ 13  libsystem_pthread.dylib             0x00007fff72dccc4d start_wqthread + 13
[13:11:17]: ▸ ), NSLocalizedRecoverySuggestion=Please unlock your device and reattach. (0xE800001A)., NSLocalizedFailureReason=Please unlock your device and reattach. (0xE800001A).})

If I don't have my iPhone connected then this doesn't happen. Maybe the underlying Xcode build commands are trying to use my physical device?

Answer 1

This occurs when a device is either connected to the machine running snapshot, or paired using Xcode 10's new wireless pairing feature.

Try unplugging your device. If you don't have any devices plugged in, try:

• In Xcode, select Window - Devices & Simulators.
• If you see any devices connected on the left, right-click them and select Unpair.