React Native app not building for Android - SyntaxError: \u can only be followed by a Unicode character sequence

Question

My App is running fine on iOS but will not run on Android. I spent ages last week getting it working, and thought it was , and the problem has returned.

Logs show

Full logs here in case there is other stuff relevant. https://pastebin.com/by6uCmPW

SyntaxError: \u can only be followed by a Unicode character sequence 

When I reload I then get a white screen, no errors are shown, and I can't get past this, and it does not change whether i connect to the debugger or not.

I've looked at the source and the error is coming from the following line

Which is this from the React Native source https://github.com/facebook/react-native/blob/a974c140db605ecbdf8d3faa7a079b7e2dcebb09/Libraries/ReactNative/YellowBox.js#L263

After refreshing, I get the following error in logcat, although nothing in the emulator.

06-14 13:52:10.467: E/art(2691): No implementation found for com.facebook.react.bridge.Inspector com.facebook.react.bridge.Inspector.instance() (tried Java_com_facebook_react_bridge_Inspector_instance and Java_com_facebook_react_bridge_Inspector_instance__)

Answer 1

Ok, I had the same issue and this is the solution I came up with that in order to make it work, I've added console.disableYellowBox = true; to index.android.js after the all imports lines.

---

As per React Native docs

YellowBoxes can be disabled during development by using console.disableYellowBox = true;. Specific warnings can be ignored programmatically by setting an array of prefixes that should be ignored: console.ignoredYellowBox = ['Warning: ...'];.

RedBoxes and YellowBoxes are automatically disabled in release (production) builds.

---

It's not an ideal workaround and probably still require some tinkering but by doing that I was able to compile the app.

Then in order to go a couple of steps deeper, I removed the recent addings (console.disableYellowBox = true; from index.android.js) and replaced {stacktraceVisible ? '\u{25BC}' : '\u{25B6}'} Stacktrace from \src\node_modules\react-native\Libraries\ReactNative\YellowBox.js with one of those next things:

• {stacktraceVisible ? '\u25BC' : '\u25B6'} Stacktrace
• {stacktraceVisible ? '-' : '-'} Stacktrace

It seems to fix the problem but not sure how elegant this way is and how you would be able to update every time after yarn or npm i.