catch IOSDeviceNotFoundError in IOSDevice.startApp() (#45011)

packages/flutter_tools/lib/src/ios/devices.dart

@@ -282,7 +282,15 @@ class IOSDevice extends Device {
       // TODO(chinmaygarde): Use mainPath, route.
       printTrace('Building ${package.name} for $id');
 
-      final String cpuArchitecture = await iMobileDevice.getInfoForDevice(id, 'CPUArchitecture');
+      String cpuArchitecture;
+
+      try {
+        cpuArchitecture = await iMobileDevice.getInfoForDevice(id, 'CPUArchitecture');
+      } on IOSDeviceNotFoundError catch (e) {
+        printError(e.message);
+        return LaunchResult.failed();
+      }
+
       final DarwinArch iosArch = getIOSArchForName(cpuArchitecture);
 
       // Step 1: Build the precompiled/DBC application if necessary.

packages/flutter_tools/test/general.shard/ios/devices_test.dart

@@ -249,6 +249,22 @@ void main() {
         Cache.enableLocking();
       });
 
+      testUsingContext('returns failed if the IOSDevice is not found', () async {
+        final IOSDevice device = IOSDevice('123');
+        when(mockIMobileDevice.getInfoForDevice(any, 'CPUArchitecture')).thenThrow(
+          const IOSDeviceNotFoundError(
+            'ideviceinfo could not find device:\n'
+            'No device found with udid 123, is it plugged in?\n'
+            'Try unlocking attached devices.'
+          )
+        );
+        final LaunchResult result = await device.startApp(mockApp);
+        expect(result.started, false);
+      }, overrides: <Type, Generator>{
+        IMobileDevice: () => mockIMobileDevice,
+        Platform: () => macPlatform,
+      });
+
       testUsingContext(' succeeds in debug mode via mDNS', () async {
         final IOSDevice device = IOSDevice('123');
         device.portForwarder = mockPortForwarder;