React Native Unhandled JS Exception: TypeError on new iOS project

Question

I started getting this error when running an existing project withreact-native run-ios. To try to see if there was something wrong with my project I ran react-native init EmptyProject to create a blank project that should work perfectly. I still get this error even with that.

I've looked at this question on stack overflow and ran ./node_modules/react-native/packager/packager.sh start --resetCache on both my existing project and the empty project to no avail. Any clues as to what might be going on?

Answer 1

After several hours of trial and error I managed to fix the problem. At this point, I don't know which specific thing fixed it, but here's all the main things I did.

• Updated node to the latest version
• brew update && brew upgrade
• brew install watchman
• Fixed all issues that came up with brew doctor
• rm -rf ./node_modules ios android
• yarn
• react-native upgrade
• Added babel-preset-react-native-stage-0 as a dev dependency in my package.json
• Added "react-native-stage-0" as a preset to my babel.rc
• ./node_modules/react-native/packager/packager.sh start --resetCache

After all of that my projects have been running smoothly again without any problems.