[iOS] Clicking just before a Special Character in a TextField causes a Crash

[mofeejegi]

Describe the bug
On iOS, whenever I'm typing some characters into a TextField, in my case an email address, I noticed that clicking just before any special Character (e.g: the '@' or '.') in the text (email) causes a crash.

Affected platforms
Select one of the platforms below:

• iOS

Versions

• Kotlin version: 1.9.22
• Compose Multiplatform version(s): 1.6.0-rc02 - 1.6.0
• OS version: iOS 17.2
• OS architecture: arm64

To Reproduce
Steps and/or the code snippet to reproduce the behavior:

1. Create a TextField and make it functional (value, onValueChanged, etc)
2. Type any number of characters, type a special character (e.g: '@'), type some more characters after
3. User your pointer or finger to click the index before the special char.
4. See crash

Expected behavior
The cursor should appear in the clicked position.

Screen Recording

Screen.Recording.2024-02-28.at.18.26.10.mov

Additional context
The error stack trace is a bit lengthy, but it starts like this:

Thread 0 Crashed::  Dispatch queue: com.apple.main-thread
0   libsystem_kernel.dylib        	       0x102c48a4c __pthread_kill + 8
1   libsystem_pthread.dylib       	       0x102ce31d0 pthread_kill + 256
2   libsystem_c.dylib             	       0x1801605cc abort + 104
3   Font Test                     	       0x100becd94 konan::abort() + 12
4   Font Test                     	       0x100bfca94 (anonymous namespace)::terminateWithUnhandledException(ObjHeader*)::$_1::operator()() const + 16
5   Font Test                     	       0x100bfc8b0 void (anonymous namespace)::$_0::operator()<(anonymous namespace)::terminateWithUnhandledException(ObjHeader*)::$_1>((anonymous namespace)::terminateWithUnhandledException(ObjHeader*)::$_1) + 80
6   Font Test                     	       0x100bfc4ec (anonymous namespace)::terminateWithUnhandledException(ObjHeader*) + 12
7   Font Test                     	       0x100bfc4a8 (anonymous namespace)::processUnhandledException(ObjHeader*) + 64
8   Font Test                     	       0x100329760 kfun:kotlinx.coroutines.internal#propagateExceptionFinalResort(kotlin.Throwable){} + 120 (CoroutineExceptionHandlerImpl.kt:27)
9   Font Test                     	       0x1002fbb1c kfun:kotlinx.coroutines.internal#handleUncaughtCoroutineException(kotlin.coroutines.CoroutineContext;kotlin.Throwable){} + 760 (CoroutineExceptionHandlerImpl.common.kt:52)
10  Font Test                     	       0x1002a0578 kfun:kotlinx.coroutines#handleCoroutineException(kotlin.coroutines.CoroutineContext;kotlin.Throwable){} + 516 (CoroutineExceptionHandler.kt:32)
11  Font Test                     	       0x100293c30 kfun:kotlinx.coroutines.StandaloneCoroutine.handleJobException#internal + 168 (Builders.common.kt:194)
12  Font Test                     	       0x1003308ec kfun:kotlinx.coroutines.JobSupport#handleJobException(kotlin.Throwable){}kotlin.Boolean-trampoline + 60 (JobSupport.kt:1031)
13  Font Test                     	       0x1002aab20 kfun:kotlinx.coroutines.JobSupport.finalizeFinishingState#internal + 1192 (JobSupport.kt:231)
14  Font Test                     	       0x1002b360c kfun:kotlinx.coroutines.JobSupport.tryMakeCompletingSlowPath#internal + 2136 (JobSupport.kt:910)
15  Font Test                     	       0x1002b2d7c kfun:kotlinx.coroutines.JobSupport.tryMakeCompleting#internal + 756 (JobSupport.kt:867)

[elijah-semyonov]

Hi, thanks for the report, I'll have a look

[okushnikov]

Please check the following ticket on YouTrack for follow-ups to this issue. GitHub issues will be closed in the coming weeks.

[babew]

Hello,

I have pretty same stack trace but the crash is from AppStore and I can't reproduce it. I saw that it isn't like the crash in this ticket but I will post my stack trace here.

#0	0x107f6dd18 in <inlined-out:<anonymous>> ()
#1	0x107f6dd18 in kfun:kotlin#apply__at__0:0(kotlin.Function1<0:0,kotlin.Unit>){0§<kotlin.Any?>}0:0 ()
#2	0x107f6dd18 in kfun:kotlinx.coroutines#handlerException(kotlin.Throwable;kotlin.Throwable){}kotlin.Throwable ()
#3	0x107f6dbfc in kfun:kotlinx.coroutines#handleCoroutineException(kotlin.coroutines.CoroutineContext;kotlin.Throwable){} ()
#4	0x107f64ecc in kfun:kotlinx.coroutines.StandaloneCoroutine.handleJobException#internal ()
#5	0x107f748fc in kfun:kotlinx.coroutines.JobSupport#handleJobException(kotlin.Throwable){}kotlin.Boolean-trampoline ()
#6	0x107f748fc in kfun:kotlinx.coroutines.JobSupport.finalizeFinishingState#internal ()
#7	0x107f792fc in kfun:kotlinx.coroutines.JobSupport.tryMakeCompletingSlowPath#internal ()
#8	0x107f792fc in kfun:kotlinx.coroutines.JobSupport.tryMakeCompleting#internal ()
#9	0x107f78b08 in <inlined-out:<anonymous>> ()
#10	0x107f78b08 in <inlined-out:loopOnState> ()
#11	0x107f78b08 in kfun:kotlinx.coroutines.JobSupport#makeCompletingOnce(kotlin.Any?){}kotlin.Any? ()
#12	0x107f63588 in kfun:kotlinx.coroutines.AbstractCoroutine#resumeWith(kotlin.Result<1:0>){} ()
#13	0x107a7f378 in <inlined-out:<anonymous>> ()
#14	0x107a7f378 in kfun:kotlin#with(0:0;kotlin.Function1<0:0,0:1>){0§<kotlin.Any?>;1§<kotlin.Any?>}0:1 ()
#15	0x107a7f378 in kfun:kotlin.coroutines.native.internal.BaseContinuationImpl#resumeWith(kotlin.Result<kotlin.Any?>){} ()
#16	0x107fac13c in kfun:kotlinx.coroutines.internal.ScopeCoroutine#afterResume(kotlin.Any?){} ()
#17	0x107f635e4 in kfun:kotlinx.coroutines.AbstractCoroutine#afterResume(kotlin.Any?){}-trampoline ()
#18	0x107f635e4 in kfun:kotlinx.coroutines.AbstractCoroutine#resumeWith(kotlin.Result<1:0>){} ()
#19	0x107a7f378 in <inlined-out:<anonymous>> ()
#20	0x107a7f378 in kfun:kotlin#with(0:0;kotlin.Function1<0:0,0:1>){0§<kotlin.Any?>;1§<kotlin.Any?>}0:1 ()
#21	0x107a7f378 in kfun:kotlin.coroutines.native.internal.BaseContinuationImpl#resumeWith(kotlin.Result<kotlin.Any?>){} ()
#22	0x107fa82f4 in kfun:kotlin.coroutines#resumeWithException__at__kotlin.coroutines.Continuation<0:0>(kotlin.Throwable){0§<kotlin.Any?>} ()
#23	0x107fa82f4 in <inlined-out:<anonymous>> ()
#24	0x107fa82f4 in kfun:kotlinx.coroutines#withContinuationContext(kotlin.coroutines.Continuation<*>;kotlin.Any?;kotlin.Function0<0:0>){0§<kotlin.Any?>}0:0 ()
#25	0x107fa82f4 in kfun:kotlinx.coroutines.DispatchedTask#run(){} ()
#26	0x107fa9758 in kfun:kotlinx.coroutines.internal.LimitedDispatcher.Worker.run#internal ()
#27	0x107fbc0f8 in kfun:kotlinx.coroutines.MultiWorkerDispatcher.$workerRunLoop$lambda$2COROUTINE$0.invokeSuspend#internal ()
#28	0x107a7f28c in kfun:kotlin.coroutines.native.internal.BaseContinuationImpl#invokeSuspend(kotlin.Result<kotlin.Any?>){}kotlin.Any?-trampoline ()
#29	0x107a7f28c in <inlined-out:<anonymous>> ()
#30	0x107a7f28c in kfun:kotlin#with(0:0;kotlin.Function1<0:0,0:1>){0§<kotlin.Any?>;1§<kotlin.Any?>}0:1 ()
#31	0x107a7f28c in kfun:kotlin.coroutines.native.internal.BaseContinuationImpl#resumeWith(kotlin.Result<kotlin.Any?>){} ()
#32	0x107fa8368 in kfun:kotlin.coroutines#resume__at__kotlin.coroutines.Continuation<0:0>(0:0){0§<kotlin.Any?>} ()
#33	0x107fa8368 in <inlined-out:<anonymous>> ()
#34	0x107fa8368 in kfun:kotlinx.coroutines#withContinuationContext(kotlin.coroutines.Continuation<*>;kotlin.Any?;kotlin.Function0<0:0>){0§<kotlin.Any?>}0:0 ()
#35	0x107fa8368 in kfun:kotlinx.coroutines.DispatchedTask#run(){} ()
#36	0x107f716f4 in <inlined-out:<anonymous>> ()
#37	0x107f716f4 in <inlined-out:<anonymous>> ()
#38	0x107f716f4 in kfun:kotlinx.cinterop#autoreleasepool(kotlin.Function0<0:0>){0§<kotlin.Any?>}0:0 ()
#39	0x107f716f4 in kfun:kotlinx.coroutines#platformAutoreleasePool(kotlin.Function0<kotlin.Unit>){} ()
#40	0x107f716f4 in kfun:kotlinx.coroutines.EventLoopImplBase#processNextEvent(){}kotlin.Long ()
#41	0x107fb6ee8 in kfun:kotlinx.coroutines.EventLoop#processNextEvent(){}kotlin.Long-trampoline ()
#42	0x107fb6ee8 in kfun:kotlinx.coroutines.BlockingCoroutine.joinBlocking#internal ()
#43	0x107fb6ee8 in kfun:kotlinx.coroutines#runBlocking(kotlin.coroutines.CoroutineContext;kotlin.coroutines.SuspendFunction1<kotlinx.coroutines.CoroutineScope,0:0>){0§<kotlin.Any?>}0:0 ()
#44	0x107fbc87c in kfun:kotlinx.coroutines#runBlocking$default(kotlin.coroutines.CoroutineContext?;kotlin.coroutines.SuspendFunction1<kotlinx.coroutines.CoroutineScope,0:0>;kotlin.Int){0§<kotlin.Any?>}0:0 ()
#45	0x107fbc87c in kfun:kotlinx.coroutines.MultiWorkerDispatcher.workerRunLoop#internal ()
#46	0x107fbc87c in kfun:kotlinx.coroutines.MultiWorkerDispatcher.<init>$lambda$1$lambda$0#internal ()
#47	0x107fbc87c in kfun:kotlinx.coroutines.MultiWorkerDispatcher.$<init>$lambda$1$lambda$0$FUNCTION_REFERENCE$5.invoke#internal ()
#48	0x107fbc87c in kfun:kotlinx.coroutines.MultiWorkerDispatcher.$<init>$lambda$1$lambda$0$FUNCTION_REFERENCE$5.$<bridge-DNN>invoke(){}#internal ()
#49	0x10948d7dc in kfun:kotlin.Function0#invoke(){}1:0-trampoline ()
#50	(null) in Worker::processQueueElement(bool) ()
#51	(null) in (anonymous namespace)::workerRoutine(void*) ()

Could you please help me find from where this crash is and how to resolve it ?

Regards,
Lyubo