Crash when passing exceptionHandler in viewModelScope.launch

[daniel-waiguru]

Describe the bug
In my ViewModel i use need to specify an exception handler when launching a coroutine in viewModelScope as below

kotlin private val exceptionHandler = CoroutineExceptionHandler { _, throwable -> } viewModelScope.launch(exceptionHandler) { //code }

but I noticed that the ViewModel injection fails and causes a crash with stacktrace as below, however upon removing the exceptionHandler the app runs without a crash
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:590) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:886) Caused by: java.lang.reflect.InvocationTargetException at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:580) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:886)  Caused by: org.koin.core.error.InstanceCreationException: Could not create instance for '[Factory: 'profile_presentation.EditProfileViewModel']' at org.koin.core.instance.InstanceFactory.create(InstanceFactory.kt:58) at org.koin.core.instance.FactoryInstanceFactory.get(FactoryInstanceFactory.kt:38) at org.koin.core.registry.InstanceRegistry.resolveInstance$koin_core(InstanceRegistry.kt:110) at org.koin.core.scope.Scope.resolveFromRegistry(Scope.kt:321) at org.koin.core.scope.Scope.resolveFromContext(Scope.kt:311) at org.koin.core.scope.Scope.stackParametersCall(Scope.kt:281) at org.koin.core.scope.Scope.resolveInstance(Scope.kt:259) at org.koin.core.scope.Scope.resolveWithOptionalLogging(Scope.kt:232) at org.koin.core.scope.Scope.get(Scope.kt:215) at org.koin.viewmodel.factory.KoinViewModelFactory.create(KoinViewModelFactory.kt:39) at androidx.lifecycle.viewmodel.ViewModelProviderImpl_androidKt.createViewModel(ViewModelProviderImpl.android.kt:34) at androidx.lifecycle.viewmodel.ViewModelProviderImpl.getViewModel$lifecycle_viewmodel_release(ViewModelProviderImpl.kt:65) at androidx.lifecycle.viewmodel.ViewModelProviderImpl.getViewModel$lifecycle_viewmodel_release$default(ViewModelProviderImpl.kt:47) at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.android.kt:91) at org.koin.viewmodel.GetViewModelKt.resolveViewModel(GetViewModel.kt:60) at org.koin.viewmodel.GetViewModelKt.resolveViewModel$default(GetViewModel.kt:44 at androidx.fragment.app.Fragment.performViewCreated(Fragment.java:3152) at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:608) at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:286) at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:2214) at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:2115) at androidx.fragment.app.FragmentManager.execPendingActions(FragmentManager.java:2052) at androidx.fragment.app.FragmentManager$5.run(FragmentManager.java:703) at android.os.Handler.handleCallback(Handler.java:959) at android.os.Handler.dispatchMessage(Handler.java:100) at android.os.Looper.loopOnce(Looper.java:232) at android.os.Looper.loop(Looper.java:317) at android.app.ActivityThread.main(ActivityThread.java:8705) at java.lang.reflect.Method.invoke(Native Method)  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:580)  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:886)  Caused by: java.lang.NullPointerException: Attempt to invoke interface method 'java.lang.Object kotlin.coroutines.CoroutineContext.fold(java.lang.Object, kotlin.jvm.functions.Function2)' on a null object reference at kotlinx.coroutines.CoroutineContextKt.hasCopyableElements(CoroutineContext.kt:36) at kotlinx.coroutines.CoroutineContextKt.foldCopies(CoroutineContext.kt:51) 2024-12-16 19:25:17.004 13141-13141 AndroidRuntime E at kotlinx.coroutines.CoroutineContextKt.newCoroutineContext(CoroutineContext.kt:15) at kotlinx.coroutines.BuildersKt__Builders_commonKt.launch(Builders.common.kt:48) at kotlinx.coroutines.BuildersKt.launch(Unknown Source:1) at kotlinx.coroutines.BuildersKt__Builders_commonKt.launch$default(Builders.common.kt:43) at kotlinx.coroutines.BuildersKt.launch$default(Unknown Source:1) at at presentation.di.FeatureProfileModulesKt.viewModelModules$lambda$1$lambda$0(FeatureProfileModules.kt:9) at presentation.di.FeatureProfileModulesKt.$r8$lambda$I4C-DS2Jr0O4j89h8zyZwNHL4z8(Unknown Source:0) at presentation.di.FeatureProfileModulesKt$$ExternalSyntheticLambda2.invoke(D8$$SyntheticClass:0) at org.koin.core.instance.InstanceFactory.create(InstanceFactory.kt:51)

To Reproduce
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4. See error

Expected behavior
The app should not crash and koin should be able to create an instance of the viewmodel

Koin module and version:
[e.g]: koin-android:4.0.0

Snippet or Sample project to help reproduce
Add a snippet or even a small sample project to help reproduce your case.

[arnaudgiuliani]

aren't you mixing Koin scope with Coroutines Scope?

[daniel-waiguru]

not really, when i have viewModelScope.launch {} koin is able to create and inject the VM but I add exceptionhandler koin fails to create the VM

[arnaudgiuliani]

there is a weird call on your EditProfileViewModel can you try to track why here?

[daniel-waiguru]

the only difference is I introduced coroutineexceptionhandler when launching a coroutine in the ViewModel scope

private val exceptionHandler = CoroutineExceptionHandler { _, throwable -> } viewModelScope.launch(exceptionHandler) { //code }