Ignore unreachable iOS devices in IOSDevice.getAttachedDevices

[mattijsf]

Fixes #23341

Related:

• idevice_id --list is returning iPhones that are not attached via USB libimobiledevice/libimobiledevice#152
• filter out devices whose connection_type is USB to fix when devices c… libimobiledevice/libusbmuxd#53 (comment)

The usbmuxd ("USB multiplexer daemon") daemon manages the list of devices and facilitates communication with them. When Apple added support for WiFi backups and syncing, they did so by extending usbmuxd, so it is very much an intended behavior. I would like to see your proposed patch to usbmuxd_get_device_list as a configuration option, though. It would also be useful if the APIs in libimobiledevice allowed restricting connects to USB so it could selected per-connection.

In practice this means that idevice_id -l also lists udid's that are not actually attached via usb and have no debugging capabilities. When flutter tries to get device meta information using ideviceinfo -u UDID it returns an exit code 255 causing fluttor doctor and other flutter devices related API's to produce errors even though there are other attached devices / simulators that work fine.

This PR basically ignores devices for which ideviceinfo fails to receive meta information but still allow devices that do provide meta information to be included.

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[mattijsf]

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[raisezhang]

This is still not a solution to this problem ?

[mattijsf]

@raisezhang I'm not sure what you mean but once this PR is merged it should fix flutter doctor producing errors when there are paired iOS devices on the network that are not attached via a usb cable.

I wouldn't call it a solution but rather a workaround until idevice_id -l has a way to filter usb-only devices.

[Hixie]

We should write a test for this. I believe the flutter_tools tests have the technology to mock processes which would help here.

[tvolkert]

We should write a test for this. I believe the flutter_tools tests have the technology to mock processes which would help here.

Yep. There's also some tests in

flutter/packages/flutter_tools/test/ios/devices_test.dart

Line 32 in 949cfcf

group('getAttachedDevices', () {

that make sue of these mocks too.

[mattijsf]

Thanks! I'll have a look. I'm somewhat new to Dart but it shouldn't be a problem to write some tests for this. I'll also have a look to catch the specific ideviceinfo's No device found with udid error instead of all error.

[mattijsf]

I added tests and specific exception handling. I chose to add a new IOSDeviceNotFoundError to keep the detection of this specific error closest to the invocation of the ideviceinfo command. Let me know if this is undesired as I could also catch the original ToolExit and put the logic inside getAttachedDevices() without a new Exception type.

[tvolkert]

LGTM, pending one small change.

[tvolkert]

LGTM. Will merge on green.

[chunlea]

This PR finally saved me! 🍻