ionic emulate “[__NSArrayM localizedDescription]: unrecognized selector sent to instance 0x7fd64840e790”

Got this error when running ionic emulate:

2015-03-16 11:13:24.112 ios-sim[50548:9106309] stderrPath: /Users/bramus/Projects/ionic/todos/platforms/ios/cordova/console.log
2015-03-16 11:13:24.113 ios-sim[50548:9106309] stdoutPath: /Users/bramus/Projects/ionic/todos/platforms/ios/cordova/console.log
2015-03-16 11:13:24.140 ios-sim[50548:9106309] -[__NSArrayM localizedDescription]: unrecognized selector sent to instance 0x7fec20d08400
2015-03-16 11:13:24.140 ios-sim[50548:9106309] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayM localizedDescription]: unrecognized selector sent to instance 0x7fec20d08400'
*** First throw call stack:
(
	0   CoreFoundation                      0x00007fff85db066c __exceptionPreprocess + 172
	1   libobjc.A.dylib                     0x00007fff87d8876e objc_exception_throw + 43
	2   CoreFoundation                      0x00007fff85db36dd -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
	3   CoreFoundation                      0x00007fff85cfaaa4 ___forwarding___ + 1028
	4   CoreFoundation                      0x00007fff85cfa618 _CF_forwarding_prep_0 + 120
	5   ios-sim                             0x000000010b2b2cc9 -[iPhoneSimulator LoadSimulatorFramework:] + 245
	6   ios-sim                             0x000000010b2b47e3 -[iPhoneSimulator runWithArgc:argv:] + 2297
	7   ios-sim                             0x000000010b2b4bb4 main + 101
	8   ios-sim                             0x000000010b2b2b84 start + 52
	9   ???                                 0x000000000000000b 0x0 + 11
)
libc++abi.dylib: terminating with uncaught exception of type NSException
/Users/bramus/Projects/ionic/todos/platforms/ios/cordova/run: line 158: 50548 Abort trap: 6           ios-sim launch "$SIMULATOR_APP_PATH" --stderr "$CORDOVA_PATH/console.log" --stdout "$CORDOVA_PATH/console.log" $TARGET_FLAG --exit
Error: /Users/bramus/Projects/ionic/todos/platforms/ios/cordova/run: Command failed with exit code 134
    at ChildProcess.whenDone (/usr/local/lib/node_modules/cordova/node_modules/cordova-lib/src/cordova/superspawn.js:131:23)
    at ChildProcess.EventEmitter.emit (events.js:98:17)
    at maybeClose (child_process.js:743:16)
    at Process.ChildProcess._handle.onexit (child_process.js:810:5)

The build succeeds fine, but the simulator cannot be launched. To fix it, update ios-sim

$ npm uninstall -g ios-sim
$ npm install -g ios-sim

After that ionic emulate should run fine again 🙂