Creating a module with New Architecture and including a .swift file introduces compiler errors

[gtokman]

Description

I'm upgrading one of our open-source libraries, which uses Swift for the logic. However, when I include swift in the podspec source_files, I get compiler errors.

Steps to reproduce

I'm running into compiler errors after updating the podspec for the module to include .swift files in the ios/ directory.

 s.source_files = "ios/**/*.{h,m,mm,cpp,swift}" <--- adding Swift

After building the development pod, I get this error:

I found a workaround by omitting the following:
1.

 s.source_files = "ios/**/*.{h,m,mm,cpp}" <--- remove swift

2. run bundle exec pod install

3. Add the .swift file manually

After building the project, there is no compiler error. This is fine for testing, but I need to update the podspec to include the file in the Compile Sources, otherwise, other errors will occur.

React Native Version

0.74.0

Affected Platforms

Runtime - iOS

Areas

TurboModule - The New Native Module System

Output of npx react-native info

System:
  OS: macOS 14.4.1
  CPU: (8) arm64 Apple M1
  Memory: 175.06 MB / 16.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 18.18.0
    path: ~/.nvm/versions/node/v18.18.0/bin/node
  Yarn:
    version: 3.6.4
    path: /opt/homebrew/bin/yarn
  npm:
    version: 9.8.1
    path: ~/.nvm/versions/node/v18.18.0/bin/npm
  Watchman:
    version: 2024.04.15.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.15.2
    path: /Users/gary/.rvm/gems/ruby-2.7.5/bin/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 23.5
      - iOS 17.5
      - macOS 14.5
      - tvOS 17.5
      - visionOS 1.2
      - watchOS 10.5
  Android SDK:
    API Levels:
      - "29"
      - "30"
      - "31"
      - "32"
      - "33"
      - "34"
    Build Tools:
      - 28.0.3
      - 30.0.2
      - 30.0.3
      - 31.0.0
      - 32.0.0
      - 32.1.0
      - 33.0.0
      - 33.0.1
      - 34.0.0
    System Images:
      - android-32 | Google APIs ARM 64 v8a
      - android-32 | Google Play ARM 64 v8a
      - android-33 | Google APIs ARM 64 v8a
      - android-33 | Google Play ARM 64 v8a
      - android-Tiramisu | Google APIs ARM 64 v8a
    Android NDK: 22.1.7171670
IDEs:
  Android Studio: 2023.2 AI-232.10300.40.2321.11668458
  Xcode:
    version: 15.4/15F31d
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.12
    path: /usr/bin/javac
  Ruby:
    version: 2.7.5
    path: /Users/gary/.rvm/rubies/ruby-2.7.5/bin/ruby
npmPackages:
  "@react-native-community/cli": Not Found
  react:
    installed: 18.3.1
    wanted: 18.3.1
  react-native:
    installed: 0.75.2
    wanted: 0.75.2
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: true
iOS:
  hermesEnabled: true
  newArchEnabled: true

Stacktrace or Logs

n/a

Reproducer

https://github.com/candlefinance/oss/tree/feat-convert-send-na

Screenshots and Videos

No response

[react-native-bot]

⚠️

Newer Version of React Native is Available!

ℹ️

You are on a supported minor version, but it looks like there's a newer patch available - 0.74.5. Please upgrade to the highest patch for your minor or latest and verify if the issue persists (alternatively, create a new project and repro the issue in it). If it does not repro, please let us know so we can close out this issue. This helps us ensure we are looking at issues that still exist in the most recent releases.

[react-native-bot]

⚠️	Missing Reproducible Example
ℹ️	We could not detect a reproducible example in your issue report. Please provide either: If your bug is UI related: a Snack If your bug is build/update related: use our Reproducer Template. A reproducer needs to be in a GitHub repository under your username.

[react-native-bot]

⚠️

Newer Version of React Native is Available!

ℹ️

You are on a supported minor version, but it looks like there's a newer patch available - undefined. Please upgrade to the highest patch for your minor or latest and verify if the issue persists (alternatively, create a new project and repro the issue in it). If it does not repro, please let us know so we can close out this issue. This helps us ensure we are looking at issues that still exist in the most recent releases.

[react-native-bot]

⚠️	Missing Reproducible Example
ℹ️	We could not detect a reproducible example in your issue report. Please provide either: If your bug is UI related: a Snack If your bug is build/update related: use our Reproducer Template

[nullishamy]

@gtokman Seen you add labels, do you have permission to delete the comment above? Almost certainly malware

[cipolleschi]

@gtokman thanks for the issue... A few points:

1. Swift is not officially supported by the New Architecture. I know it's something big that is missing, but we don't have the resources to work on that at the moment. I hope that this will come soon.
2. Swift and C++ does not really work well together. Yes, we have the Swift/Cxx interoperability but it is not complete sadly and I don't think it is stable enough to be used
3. It looks like that your pod is failing before some swift file is trying to import the <memory> C++ module. That could also happen for transitive dependencies. Swift can't import C++ modules, hence the failure.

[gtokman]

@cipolleschi, thanks for the context.

3. It looks like that your pod is failing before some swift file is trying to import the <memory> C++ module. That could also happen for transitive dependencies. Swift can't import C++ modules, hence the failure.

I mentioned that I found a workaround. My thought was that a Build Setting was not being set correctly, which led to the pod failing to compile if I included Swift source_files. Do you have an idea of what would be different? I guess I can try to diff the .xcodeproj. of the generated vs. manually adding the file.

[cipolleschi]

when you add the swift file manually, Xcode usually creates some bridging headers and extra configuration files.
We need to look into what is generated to see how Xcode resolve the issue and then "commit" those files into the library.

I can see if I can find some time to look into it, but it will likely happen in a couple of weeks as next week we have React Universe and I'll be in Poland for the Conference.

[gtokman]

when you add the swift file manually, Xcode usually creates some bridging headers and extra configuration files. We need to look into what is generated to see how Xcode resolve the issue and then "commit" those files into the library.

I can see if I can find some time to look into it, but it will likely happen in a couple of weeks as next week we have React Universe and I'll be in Poland for the Conference.

Appreciate it @cipolleschi!

I do see the alert in Xcode for the bridging header, but I don't create it. Bridging headers are for Obj-C -> Swift. To use Swift -> Obj-C you just need to import the generated Swift headers i.e Send.swift -> #import "candlefinance_send-Swift.h".