Summary: See: http://blog.nparashuram.com/2019/10/debugging-react-native-ios-apps-with.html When using direct debugging with JavaScriptCore, Safari Web Inspector doesn't pick up the source map over the network. Instead, as far as I can tell, it expects you to pass the source URL at the time you load your bundle: https://developer.apple.com/documentation/javascriptcore/jscontext/1451384-evaluatescript?language=objc . This leads to a very sub-par developer experience debugging the JSbundle directly. It will however, pick up an inline source map. Therefore, let's add a way to have React Native tell metro to request an inline source map. I did this by modifying `RCTBundleURLProvider` to have a new query parameter for `inlineSourceMap`, and set to true by default for JSC. [IOS] [ADDED] - Added support to inline the source map via RCTBundleURLProvider Pull Request resolved: https://github.com/facebook/react-native/pull/37878 Test Plan: I can put a breakpoint in RNTester, via Safari Web Inspector, in human readable code :D <img width="1728" alt="Screenshot 2023-06-14 at 4 09 03 AM" src="https://github.com/facebook/react-native/assets/6722175/055277fa-d887-4566-9dc6-3ea07a1a60b0"> Reviewed By: motiz88 Differential Revision: D46855418 Pulled By: huntie fbshipit-source-id: 2134cdbcd0a3e81052d26ed75f83601ae4ddecfe
RNTester
The RNTester showcases React Native views and modules.
Running this app
Before running the app, make sure you ran:
git clone https://github.com/facebook/react-native.git
cd react-native
yarn install
Running on iOS
If you are testing non-fabric component, modify the fabric_enabled flag in RNTester's Podfile.
fabric_enabled = false
Also, if you previously built RNTester with fabric enabled, you might need to clean up the build files and Pods.
# Clean the generated files and folders to clean install RNTester
cd packages/rn-tester
yarn clean-ios
If you are still having a problem after doing the clean up (which can happen if you have built RNTester with older React Native versions where files were generated inside the react-native folder.), the best way might be to clean-install react-native (e.g. remove node_modules and yarn install).
Both macOS and Xcode are required.
cd packages/rn-tester- Install Bundler:
gem install bundler. We use bundler to install the right version of CocoaPods locally. - Install Bundler and CocoaPods dependencies:
bundle install && bundle exec pod installoryarn setup-ios-hermes. In order to use JSC instead of Hermes engine, run:USE_HERMES=0 bundle exec pod installoryarn setup-ios-jscinstead. - Open the generated
RNTesterPods.xcworkspace. This is not checked in, as it is generated by CocoaPods. Do not openRNTesterPods.xcodeprojdirectly.
Note for M1 users
If you own a Mac M1 laptop, you need to run some different commands to install and run cocoapods.
sudo arch -x86_64 gem install ffi: this installs theffipackage to load dynamically-linked libraries.arch -x86_64 pod install: this runpod installwith the right architecture.
Running on Android
You'll need to have all the prerequisites (SDK, NDK) for Building React Native installed.
Start an Android emulator.
cd packages/rn-tester
# In order to use Hermes engine, run `yarn install-android-hermes` instead.
yarn install-android-jsc
yarn start
Note: Building for the first time can take a while.
Open the RNTester app in your emulator.
If you want to use a physical device, run adb devices, then adb -s <device name> reverse tcp:8081 tcp:8081.
See Running on Device for additional instructions on using a physical device.
Running with Buck
Follow the same setup as running with gradle.
Install Buck from here.
Run the following commands from the react-native folder:
./gradlew :ReactAndroid:packageReactNdkLibsForBuck
buck fetch rntester
buck install -r rntester
./scripts/packager.sh
Note: The native libs are still built using gradle. Full build with buck is coming soon(tm).
Building from source
Building the app on both iOS and Android means building the React Native framework from source. This way you're running the latest native and JS code the way you see it in your clone of the github repo.
This is different from apps created using react-native init which have a dependency on a specific version of React Native JS and native code, declared in a package.json file (and build.gradle for Android apps).