App crashes when error "Compiling JS failed: 1:1:unrecognized Unicode character lufffd" is found

[ElielC]

Hello.

During a test in a environment simulating a production we encountered a error, Compiling JS failed, while downloading a remote bundle.
If we use the remote entry as our dev one, during the tests the error disappears, this indicates that there is a problem on our pipeline that moves our bundles to the "productive environment" or a problem in the environment.

The issue then is not that an error occurs, but the behavior of the app when encountering the error, as it would be problematic if the app crashed during production.

What is causing the app to crash? is there a way to change this behavior?

[jbroma]

are you using SwcJsMinimizerRspackPlugin by any chance?

[ElielC]

We are using the Terser plugin:

		optimization: {
			minimize: mode === "production",
			minimizer: [
				new TerserPlugin({
					test: /\.(js)?bundle(\?.*)?$/i,
					extractComments: false,
					terserOptions: {
						compress: {
							drop_console: true
						}
					}
				})
			]
		},

That app appears to fetch the manifest but fail when loading the container.js.bundle file.

Speaking with the team responsible for the environment, there is a gateway api in between the s3 bucket.

The same bundle files when using cloudfront on our dev environment work fine

[ElielC]

The problem in our the environment was a missing header: Content-Type: application/octet-stream

But even still is the behavior of crashing the app expected?

[jbroma]

To be frank with you - I've never ran into this kind of issue before. Out of curiosity, did that happen when fetching bundle as Hermes bytecode or plain JS bundle?

[ElielC]

Hermes bytecode

[jbroma]

Was this limited to Android, or the same thing was happening on iOS?

[ElielC]

As of now the team only validated on Android, will try to reproduce on iOS