Configure Babel to include sibling modules referenced by alias into compilation

Question

I have the following file structure:

application1
|pacakge.json
|src
||file1.ts
widget-lib
|package.json
|src
||file2.ts
||index.ts

.\widget-lib\src\index.ts bundles and reexports everything in widget-lib package.

export * from '.\file2'

.\application1\src\file1.ts and other files refence widget-lib by alias

import { foo } from 'widget-lib';

I'm compiling .\application1\src\ with Babel into .\application1\build-test\, how do I instruct Babel to also include widget-lib into this particular compilation? My goal is to produce a folder with all JS files needed to debug unit tests in modern node with esm package - just strip down TS types and put resulting JS files into proper place, like this:

application1
|build-test
||application1
|||src
||||file1.js
||widget-lib
|||src
||||index.js
||||file2.js

I'm using https://github.com/tleunen/babel-plugin-module-resolver to rewrite alias paths like 'widget-lib' to expected relative paths, I just need to instruct babel to also include the actual files from widget-lib into .\build-test\widget-lib folder. I tried passing both .\application1\src and .\widget-lib\src together to Babel, but than it outputs content of both .\src folders into one.

Answer 1

I ended up running several babel process in parallel, spawning them with a node script as described here Execute a command line binary with Node.js and using the script to analyze their output and emit additional information.