Template tabs@48 is broken

[durasj]

Which package manager are you using? (Yarn is recommended)

yarn

Summary

When we build a production IPA for iOS, the app crashes instantly with Invariant Violation: TurboModuleRegistry.getEnforcing(...): 'DevSettings' could not be found.:

default	17:06:14.420437+0200	test48	Not internal release, disabling SIRL
default	17:06:14.420512+0200	test48	Adding securityd connection to pool, total now 1\
error	17:06:14.427999+0200	test48	Invariant Violation: TurboModuleRegistry.getEnforcing(...): 'DevSettings' could not be found. Verify that a module by this name is registered in the native binary., js engine: hermes
error	17:06:14.429765+0200	test48	Invariant Violation: "main" has not been registered. This can happen if:
* Metro (the local dev server) is run from the wrong folder. Check if Metro is running, stop it and restart it in the current project.
* A module failed to load due to an error and `AppRegistry.registerComponent` wasn't called., js engine: hermes
error	17:06:14.429812+0200	test48	Unable to find module for RedBox
error	17:06:14.429861+0200	test48	Unhandled JS Exception: Invariant Violation: TurboModuleRegistry.getEnforcing(...): 'DevSettings' could not be found. Verify that a module by this name is registered in the native binary., js engine: hermes
default	17:06:14.431931+0200	test48	*** Terminating app due to uncaught exception 'RCTFatalException: Unhandled JS Exception: Invariant Violation: TurboModuleRegistry.getEnforcing(...): 'DevSettings' could not be found. Verify that a module by this name is registered in the native binary., js engine: hermes', reason: 'Unhandled JS Exception: Invariant Violation: TurboModuleRegistry.getEnforcing(...): 'DevSettings' could not be found. Verify that a module by this name is registered in the na..., stack:
invariant@1453:25
getEnforcing@1431:27
anonymous@38522:49
loadModuleImplementation@150:13
guardedLoadModule@88:37
metroRequire@37:91
anonymous@38505:61
loadModuleImplementation@150:13
guardedLoadModule@88:37
metroRequire@37:91
anonymous@41007:31
loadModuleImplementation@150:13
guardedLoadModule@88:37
metroRequire@37:91
anonymous@40999:30
loadModuleImplementation@150:13
guardedLoadModule@88:37
metroRequire@37:91
anonymous@40977:47
loadModuleImplementation@150:13
guardedLoadModule@88:37
metroRequire@37:91
anonymous@40942:32
loadModuleImplem<…>

The same exact error occurs on a fresh tabs@48 template with zero changes. We can reproduce this on two completely different Apple devices - one Mac mini and one MacBook Air.

It works fine in dev client mode with Expo Go. It also works fine on Android, with an empty 48 expo template (so no router) and tabs@49. And no, unfortunately, we can't switch to v2 with SDK 49 yet.

Minimal reproducible example

1. Clone https://github.com/durasj/expo-router-48-broken-reproduce.
2. Run yarn install.
3. Create a production build, so, for example, run eas build --platform ios --profile preview --local to get an IPA to run on a device and try to open it.

[durasj]

After a ton of trial & error, I narrowed it down to these two lines from expo-router:

https://github.com/expo/router/blob/expo-router%401.7.7/packages/expo-router/entry.js#L3,L7

import "@expo/metro-runtime";

// This file should only import and register the root. No components or exports
// should be added here.
import { renderRootComponent } from "expo-router/src/renderRootComponent";

If I make my own entry file and drop those two, it works. Of course, I have to switch to import { registerRootComponent } from 'expo';.

[zRelux]

@durasj Can you explain the solution a bit further?

[durasj]

@zRelux In your index.js, don't import expo-router/entry. Instead, do:

const { App } = require('expo-router/_app');
registerRootComponent(App);

Ideally, only in production (!__DEV__), though, as their entry file has some additional logic that is especially helpful during the development.