[Feature request] source map generation

[vstefanovic97]

I would like to request for the rollup-gjs-plugin to return map (sourceMaps) as we as the code field.

Example where this can be useful, when we are building a v2 addon with the standard v2 blueprint with rollup and let's say we want to use babel-plugin-istanbul to instrument our code, we would need the original source maps so that istanbul would know exactly how to map it's coverage to the original .gjs/.gts source files.

This is also related to embroider-build/content-tag#61 which is needed in order for this to be implemented here

[NullVoxPopuli]

If we use magic-string in content-tag to generate a sourcemap, we could change the rollup plugin to something like this:

let { code, sourceMap } = processor.process(input, { id, sourceMap: true });

return {
  code,
  map: sourceMap,
};

this could be a non-breaking change to content-tag (different return type based on type of the second arg to process)

[ef4]

The rust side of content-tag already supports source maps. The JS bindings just don't use it yet.

[vstefanovic97]

Closing issue as completed in #1786