Sourcemaps with esbuild not working.

[ioev]

I'm actually not sure if this is a problem with jsbundling-rails or bundler, but:

I'm bundling my js/css via esbuild --bundle --watch --sourcemap which results in 2 files being generated in assets/builds, application.js and application.js.map. The application requests these via:
/assets/application.debug-1caabe86ba2a00618598d8d7d5a8fe6c57a594dd7babeec3fe6e3ff3ce9185e1.js
/assets/application.js-4112a73edf43c31165109b2906c7bcda25ff0505d405213d39501087ea154f74.map

The sourcemap url does not exist.

If I look at the bottom of my application.js in the build folder, it ends with:

//# sourceMappingURL=application.js.map

And if I look at the end of the file coming from a server request, it ends with:

//# sourceMappingURL=/assets/application.js-5673ea8258e5021fb9befebfe3f84d5c8ff21ee5fd1e52b4f54b8347a5bbfbbb.map
//!
;

//# sourceMappingURL=application.js-4112a73edf43c31165109b2906c7bcda25ff0505d405213d39501087ea154f74.map

The first source map url works, the second does not. I'm assuming bundler is somehow fixing the existing sourcemap definition, but then also adding it's own?

Running esbuild without --sourcemaps ends up with sourcemaps that work on the client, but they are not useful.

Is there a workflow that will work here?

[jdbann]

@ioev I had this too, but digging around other esbuild issues led me to this fix which worked for me: #40 (comment)

[dhh]

For others, you must set config.assets.debug = false.

[ioev]

This fix in conjunction with:
#40 (comment)

allows the sourcemaps to be located, but they still don't seem to actually work in the browser.

I also tried --entry-names=[dir]/[name]-[hash].digested in esbuild, which generates .digested.js files that sprockets can't even locate.

ActionView::Template::Error (The asset "application.js" is not present in the asset pipeline.

(Rails 6.1.4.1 and Sprockets 4.0.2/Sprockets-rails 3.4.2 btw)

[dhh]

You need to using sprockets-rails 3.4.2+ for this to work.