loadBundleAtURL does not get called anymore

[tux2nicolae]

Description

We noticed after upgrading to 0.79.3 the loadBundleAtURL function defined in AppDelegate.mm does not get called anymore, this function is similar to loadSourceForBridge only for new architecture, last version that we know this worked was on 0.77

Steps to reproduce

Add

- (void)loadBundleAtURL:(NSURL *)sourceURL
             onProgress:(RCTSourceLoadProgressBlock)onProgress
             onComplete:(RCTSourceLoadBlock)loadCallback
{
}

in AppDelegate.mm and run the project

React Native Version

0.79.3

Affected Platforms

Runtime - iOS

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

System:
  OS: macOS 15.5
  CPU: (8) arm64 Apple M1
  Memory: 119.88 MB / 8.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 18.20.4
    path: ~/.nvm/versions/node/v18.20.4/bin/node
  Yarn: Not Found
  npm:
    version: 10.7.0
    path: ~/.nvm/versions/node/v18.20.4/bin/npm
  Watchman:
    version: 2024.08.26.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.15.2
    path: /opt/homebrew/bin/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 24.4
      - iOS 18.4
      - macOS 15.4
      - tvOS 18.4
      - visionOS 2.4
      - watchOS 11.4
  Android SDK: Not Found
IDEs:
  Android Studio: Not Found
  Xcode:
    version: 16.3/16E140
    path: /usr/bin/xcodebuild
Languages:
  Java: Not Found
  Ruby:
    version: 2.6.10
    path: /usr/bin/ruby
npmPackages:
  "@react-native-community/cli":
    installed: 18.0.0
    wanted: 18.0.0
  react:
    installed: 19.0.0
    wanted: 19.0.0
  react-native:
    installed: 0.79.3
    wanted: 0.79.3
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: true
iOS:
  hermesEnabled: false
  newArchEnabled: true

Stacktrace or Logs

.

MANDATORY Reproducer

https://github.com/tux2nicolae/reaact-native-bug

Screenshots and Videos

No response

[react-native-bot]

Warning

Missing reproducer: We could not detect a reproducible example in your issue report. Reproducers are mandatory and we can accept only one of those as a valid reproducer:

• For majority of bugs: send us a Pull Request with the RNTesterPlayground.js edited to reproduce your bug.
• If your bug is UI related: a Snack
• If your bug is build/upgrade related: a project using our Reproducer Template

You can read more about about it on our website: How to report a bug.

[migueldaipre]

Hi @tux2nicolae, please create a minimal reproducer for the issue using our Reproducer Template

[tux2nicolae]

Hi, @migueldaipre will do that, but the problem comes from RCTHost.mm

Starting with 0.78 the _hostDelegate is in fact of type RCTReactNativeFactory, wich won't respond to respondsToSelector:@selector(loadBundleAtURL:onProgress:onComplete:) due to the fact it does not have the method implemented. It should look for and try to select if the user has the method implemented instead of RCTReactNativeFactory.

We solved the problem for us by creating a patch, but this is definitely a regression in react-native, later this day I will also try to create a reproducer based on the template you provided to conform with the issues policy.

[tux2nicolae]

Hi @migueldaipre, I've added a reproducer as you requested

https://github.com/tux2nicolae/reaact-native-bug

p.s Sorry for the minor tipo in the repository name

[chrisbianca]

@tux2nicolae are you able to share the patch you made to get this to work?

[MPiccinato]

This is the patch I came up with for 0.83.0

diff --git a/node_modules/react-native/ReactCommon/react/runtime/platform/ios/ReactCommon/RCTHost.mm b/node_modules/react-native/ReactCommon/react/runtime/platform/ios/ReactCommon/RCTHost.mm
index 5c7bf6b..ff94b3e 100644
--- a/node_modules/react-native/ReactCommon/react/runtime/platform/ios/ReactCommon/RCTHost.mm
+++ b/node_modules/react-native/ReactCommon/react/runtime/platform/ios/ReactCommon/RCTHost.mm
@@ -7,6 +7,7 @@
 
 #import "RCTHost.h"
 #import "RCTHost+Internal.h"
+#import "RCTReactNativeFactory.h"
 
 #import <React/RCTAssert.h>
 #import <React/RCTBridgeModule.h>
@@ -372,12 +373,24 @@ - (void)instance:(RCTInstance *)instance didInitializeRuntime:(facebook::jsi::Ru
 
 - (void)loadBundleAtURL:(NSURL *)sourceURL
              onProgress:(RCTSourceLoadProgressBlock)onProgress
-             onComplete:(RCTSourceLoadBlock)loadCallback
-{
-  if ([_hostDelegate respondsToSelector:@selector(loadBundleAtURL:onProgress:onComplete:)]) {
-    [_hostDelegate loadBundleAtURL:sourceURL onProgress:onProgress onComplete:loadCallback];
+             onComplete:(RCTSourceLoadBlock)loadCallback {
+  if ([_hostDelegate isKindOfClass:[RCTReactNativeFactory class]]) {
+    RCTReactNativeFactory *factory = (RCTReactNativeFactory *)_hostDelegate;
+
+    if ([factory.delegate respondsToSelector:@selector
+                          (loadBundleAtURL:onProgress:onComplete:)]) {
+      [factory.delegate loadBundleAtURL:sourceURL
+                             onProgress:onProgress
+                             onComplete:loadCallback];
+    } else {
+      [RCTJavaScriptLoader loadBundleAtURL:sourceURL
+                                onProgress:onProgress
+                                onComplete:loadCallback];
+    }
   } else {
-    [RCTJavaScriptLoader loadBundleAtURL:sourceURL onProgress:onProgress onComplete:loadCallback];
+    [RCTJavaScriptLoader loadBundleAtURL:sourceURL
+                              onProgress:onProgress
+                              onComplete:loadCallback];
   }
 }

[react-native-bot]

This issue is stale because it has been open 180 days with no activity. Remove stale label or comment or this will be closed in 7 days.