feat: support hidden source maps to map error stack traces from crash reports

[DimitarTachev]

The hidden-source-map is the same as source-map, but it doesn't add a reference comment to the bundle. It is meant to be used when you only want SourceMaps to map error stack traces from error reports from tools like crashlytics, but you don't want to expose your SourceMap for the development tools in the release builds.

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Related to: #817

[Fatme]

Maybe it'll be better to extract this function to common place and reuse it in all config files.

[farfromrefug]

@DimitarTachev is there an example somewhere on how to actually use source map? How to have stack replaced using source maps?

[DimitarTachev]

@farfromrefug, unfortunately, this example is still in our backlog. We've just validated that the source maps are properly generated externally (having the proper content and not linked in the source files) as described in the related issue.

@edusperoni, did you try this feature and could you share some info about the steps for applying the external source maps in the error reporting tools?

[edusperoni]

@farfromrefug @DimitarTachev

You could try online tools like https://sourcemaps.info/

Usually debugging the stacktrace with hidden sourcemaps will be a pain, but basically you'll get something like: Error on line 1 column 3000 on 1.js, you then get 1.js.map and use sourcemap-lookup like so: sourcemap-lookup 1.js.map:1:3000 and it'll output the actual line. I've done successfully in the past, so it should work :)

[farfromrefug]

@DimitarTachev @edusperoni i am more for other approaches. I actually have 2 of them:

• live dev source map handling(Crucial when using webpack): there i use source-map-support. Mostly works on android. Except for .android.ts and .ios.ts files. Can't work on iOS right now [FR] error stack : same format as android and prepareStackTrace support ios-jsc#1135
• production / testing versions: i now use bugsnag. Did a nativescript plugin for it https://github.com/Akylas/nativescript-bugsnag. Sourcemap are automatically uploaded. The good thing is that you dont need to include sourcemaps in the final app. Still have an issue on iOS filtering .map from the final package.

Now i was asking here to see if the {N} team had other solutions. It's been said for a long time that {N} supports source maps, though i could never find a way to actually use them ...
It really should be handled correctly.

[gajus]

It is not clear how to make the sourcemap file contenthash match the original script.

#817 (comment)