[0.80.0][Android] `Attempt to invoke interface method 'java.util.Iterator java.util.Collection.iterator()' on a null object reference` crash on app startup

[isekovanic]

Description

Hello React Native team,

Under certain conditions, a vanilla React Native CLI app will always crash on startup, as soon as its MainApplication runs on React Native 0.80.0.

Namely, the error detailed just below is being thrown every single time regardless of whether it's a release/debug build. After some digging, I found that the offending line is this one here. However, despite how it seems the actual issue is not in one of the core RN modules.

After running the following short snippet:

val packages = PackageList(this@MainApplication).packages
for (pkg in packages) {
    if (pkg is ViewManagerOnDemandReactPackage) {
        Log.d("ViewManagerCheck", "👀 Found ViewManager package: ${pkg.javaClass.name}")
    }
}

in onCreate() within MainApplication.kt, I managed to comb the issue down to a couple of view managers that stemmed from external libraries (react-native-gesture-handler, react-native-svg and @react-native-camera-roll/camera-roll). The real culprit (in the repository I work on) turned out to be @react-native-camera-roll/camera-roll, because it does this, which will always result in a crash before anything else can happen in the app.

Combing through the 0.80.0 PRs, I believe that this one is the one that introduced this regression during the port of ReactInstance from Java to Kotlin. If we look at the old implementation, we can see that there's a null check in place which prevented this from happening, whereas the new one does not.

Of course, @react-native-camera-roll/camera-roll is just an example that I managed to encounter - I'm sure many other libraries who possibly return null will also cause any React Native app using them to crash on startup. I used it in the reproducer just as an example and I'll open a PR/issue on @react-native-camera-roll/camera-roll a bit later, but I believe that this might need to be addressed upstream as well.

Steps to reproduce

1. git clone https://github.com/isekovanic/rn-0.80.0-android-crash-reproducer.git
2. cd rn-0.80.0-android-crash-reproducer/ReproducerApp
3. yarn install
4. yarn run android --list-devices (and select your device/emulator)

React Native Version

0.80.0

Affected Platforms

Runtime - Android

Output of npx @react-native-community/cli info

System:
  OS: macOS 15.4.1
  CPU: (10) arm64 Apple M1 Pro
  Memory: 173.17 MB / 16.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 22.13.1
    path: ~/.nvm/versions/node/v22.13.1/bin/node
  Yarn:
    version: 1.22.22
    path: /opt/homebrew/bin/yarn
  npm:
    version: 8.19.4
    path: ~/Projects/stream-chat-react-native/node_modules/.bin/npm
  Watchman:
    version: 2024.08.12.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.16.2
    path: /opt/homebrew/bin/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 24.2
      - iOS 18.2
      - macOS 15.2
      - tvOS 18.2
      - visionOS 2.2
      - watchOS 11.2
  Android SDK: Not Found
IDEs:
  Android Studio: 2024.3 AI-243.26053.27.2432.13536105
  Xcode:
    version: 16.2/16C5032a
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.12
    path: /usr/bin/javac
  Ruby:
    version: 3.3.4
    path: /opt/homebrew/opt/ruby/bin/ruby
npmPackages:
  "@react-native-community/cli":
    installed: 19.0.0
    wanted: 19.0.0
  react:
    installed: 19.1.0
    wanted: 19.1.0
  react-native:
    installed: 0.80.0
    wanted: ^0.80.0
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: true
iOS:
  hermesEnabled: true
  newArchEnabled: true

Stacktrace or Logs

[runtime not ready]: Error: Exception in HostFunction: java.lang.NullPointerException: Attempt to invoke interface method 'java.util.Iterator java.util.Collection.iterator()' on a null object reference
                                                                                                    	at java.util.AbstractCollection.addAll(AbstractCollection.java:335)
                                                                                                    	at com.facebook.react.runtime.ReactInstance$BridgelessViewManagerResolver.getLazyViewManagerNames(ReactInstance.kt:547)
                                                                                                    	at com.facebook.react.runtime.ReactInstance._init_$lambda$2(ReactInstance.kt:228)
                                                                                                    	at com.facebook.react.runtime.ReactInstance.$r8$lambda$kHxgB1VvaqAOBtRVp4CgY0gnLGo(Unknown Source:0)
                                                                                                    	at com.facebook.react.runtime.ReactInstance$$ExternalSyntheticLambda3.getConstants(D8$$SyntheticClass:0)
                                                                                                    	at com.facebook.jni.NativeRunnable.run(Native Method)
                                                                                                    	at android.os.Handler.handleCallback(Handler.java:959)
                                                                                                    	at android.os.Handler.dispatchMessage(Handler.java:100)
                                                                                                    	at com.facebook.react.bridge.queue.MessageQueueThreadHandler.dispatchMessage(MessageQueueThreadHandler.kt:21)
                                                                                                    	at android.os.Looper.loopOnce(Looper.java:249)
                                                                                                    	at android.os.Looper.loop(Looper.java:337)
                                                                                                    	at com.facebook.react.bridge.queue.MessageQueueThreadImpl$Companion.startNewBackgroundThread$lambda$1(MessageQueueThreadImpl.kt:175)
                                                                                                    	at com.facebook.react.bridge.queue.MessageQueueThreadImpl$Companion.$r8$lambda$ldnZnqelhYFctGaUKkOKYj5rxo4(Unknown Source:0)
                                                                                                    	at com.facebook.react.bridge.queue.MessageQueueThreadImpl$Companion$$ExternalSyntheticLambda0.run(D8$$SyntheticClass:0)
                                                                                                    	at java.lang.Thread.run(Thread.java:1012)
                                                                                                    , js engine: hermes

MANDATORY Reproducer

https://github.com/isekovanic/rn-0.80.0-android-crash-reproducer

Screenshots and Videos

crash-reproduction-showcase.mp4

[Bobslegend61]

Please is there a way around this? Having this issue as well

[OguzEkinci]

same issue

[ngxhuyhoang]

Same issue

[cipolleschi]

@cortinico can you have a look at this? It seems like this is a Kotlin migration went wrong.

[r0b0t3d]

This need to be fixed in library. While waiting, you can use this workaround

1. Search for getViewManagerNames to find all the libs which have this implementation

2. Make sure they are not returning null, if yes, you can edit and use patch-package to store what you update in the lib

@Override
  public List<String> getViewManagerNames(ReactApplicationContext reactContext) {
    return new ArrayList<String>();
  }

[cortinico]

Thank you @isekovanic for reporting this. As other mentioned, the root cause of the issue is Java libraries that are not respecting the signature of ViewManagerOnDemandReactPackage.

Anyway I've included a patch for this problem here:

• Fix crash on ReactInstance due to null returned for getViewManagerNames #52035

This will ship in 0.80.1