sentryMetroSerializer cannot read size property of undefined importBundleNames

[Raraku]

OS:

• [ ] Windows
• [*] MacOS
• [ ] Linux

Platform:

• [ *] iOS
• [ ] Android

SDK:

• [*] @sentry/react-native (>= 1.0.0)
• [ *] react-native-sentry (<= 0.43.2)

SDK version: 5.19.0

react-native version: 0.73.1

Are you using Expo?

• [ ] Yes
• [ *] No

Are you using sentry.io or on-premise?

• [* ] sentry.io (SaaS)
• [ ] on-premise

If you are using sentry.io, please post a link to your issue so we can take a look:

Configuration:

(@sentry/react-native)

Sentry.init({
  dsn: 'https://[email protected]/...'
  // other options
});

---

I have the following issue:

Following the docs and using the SentryMetroSerializer made my application fail to build or run locally. This error was first spotted on our eas build ci pipeline and I reproduced it manually in xcode. Run, build and archive operations all fail with this enabled. metro.config.js had the default configuration and wasn't customized in any way, so I replaced it entirely with this

Steps to reproduce:

• Follow the steps on sentry's website. Replace metro configuration with:

    const {
      createSentryMetroSerializer,
    } = require("@sentry/react-native/dist/js/tools/sentryMetroSerializer");
  
    const config = {
      serializer: {
        customSerializer: createSentryMetroSerializer(),
      },
    };
  
    module.exports = mergeConfig(getDefaultConfig(__dirname), config);```
  
  
  

Actual result:

It produces this undefined error Metro has encountered an error: Cannot read properties of undefined (reading 'size'):

  23 |   const output = [];
  24 |
> 25 |   if (importBundleNames.size) {
     |                         ^
  26 |     const importBundleNamesObject = Object.create(null);
  27 |     importBundleNames.forEach((absolutePath) => {
  28 |       const bundlePath = path.relative(options.projectRoot, absolutePath);

RCTFatal
__28-[RCTCxxBridge handleError:]_block_invoke
_dispatch_call_block_and_release
_dispatch_client_callout
_dispatch_main_queue_drain
_dispatch_main_queue_callback_4CF
__CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__
__CFRunLoopRun
CFRunLoopRunSpecific
GSEventRunModal
-[UIApplication _run]
UIApplicationMain
main
start_sim
0x0
0x0

Expected result: Metro should bundle the app successfully. I reverted the changes and the application worked immediately.

[krystofwoldrich]

Hi @Raraku, thank you for the message, you mentioned EAS Build, what version of React Native and Expo are you using? Can you check what version of metro package is in node_modules/metro of your project?

[krystofwoldrich]

The cause of the error might be the same as https://github.com/getsentry/sentry-react-native/issues/3622.

[krystofwoldrich]

Closing this due to inactivity. If this is still an issue feel free to comment here or open a new issue if the context changed.

[NabeelZanabeet]

I had the same issue in a monorepo setup

Fixed by

1. I had dependency conflicts, had metro-config, metro-react-native-babel-preset and @react-native/metro-config present in my package.json

• removed old ones (metro-config, metro-react-native-babel-preset)
• kept official one for latest RN 0.73.6 which is "@react-native/metro-config": "0.73.5"

2. Ensure metro dependencies are not hoisted and available at package node_modules, not root mono repo node_modules at root package.json add to achieve that

"nohoist": [ "**/@react-native/**", ]

[alexincore]

@NabeelZanabeet thank you for the hint. In my case the problem was "@react-native-community/cli-plugin-metro": "^9.1.1" that was loading a wrong version of metro-config