HMR has some Error!

[NiuGuohui]

Environment

• Android
• Use TypeScript

Description

When I changed App.tsx,the HMR report an error.

Reproducible Demo

RN official demo:

index.js

import {AppRegistry} from 'react-native';
import App from './App';
import {name as appName} from './app.json';

AppRegistry.registerComponent(appName, () => App);

[zamotany]

Can you post which React Native version you're using?

[NiuGuohui]

Can you post which React Native version you're using?

0.64.0

[OliverNi]

I had the same issue before when hermes was disabled.
Try setting enableHermes to true in android/app/build.gradle.

Here's what mine looks like:

project.ext.react = [
    enableHermes: true,
    bundleCommand: "webpack-bundle",
    bundleInDebug: false
]

[zamotany]

Can someone create a repro project where this issue can be seen? In TesterApp the HMR works both with and without Hermes on Android.

[OliverNi]

https://github.com/OliverNi/react-native-app-nativepack
This can be used to reproduce the issue.
The TesterApp in the nativepack repo works for me as well. I also tried to extract to TesterApp to a separate project and changed nativepack to an external dependency and the issue was reproducible in that project as well.

It fails when evaluating the script in loadHmrUpdate so it's pretty difficult to debug.

      if (globalEvalWithSourceUrl) {
        globalEvalWithSourceUrl(script, null);
      } else {
        // Fails here
        eval(script);
      }

[NiuGuohui]

https://github.com/NiuGuohui/nativepack-issue-29
This repo can be seen this issue.

[zamotany]

I think I got the fix for it. @OliverNi @NiuGuohui can you update @callstack/nativepack to 1.4.2-beta.0 and check if the issue is gone? Also when testing keep in mind this limitation: https://github.com/callstack/nativepack#hot-module-replacement--react-refresh

[NiuGuohui]

I think I got the fix for it. @OliverNi @NiuGuohui can you update @callstack/nativepack to 1.4.2-beta.0 and check if the issue is gone? Also when testing keep in mind this limitation: https://github.com/callstack/nativepack#hot-module-replacement--react-refresh

Thank you, the issue has been eliminated.:smile: