ts-node-loader.js

// This loader integrates `ts-node` loader with `tsconfig-paths` ability to 
// resolve paths with Typescript path mappings, thanks to that, this module 
// can be loaded directly from Typescript sources using `ts-node`:
// 
// `node --experimental-specifier-resolution=node --loader ./ts-node-loader.js ./src/main.ts`
// 
// Source: https://github.com/TypeStrong/ts-node/discussions/1450
//

import { pathToFileURL } from 'url';
import { resolve as resolveTs, getFormat, transformSource, load } from 'ts-node/esm';
import * as tsConfigPaths from 'tsconfig-paths'

export { getFormat, transformSource, load };

const { absoluteBaseUrl, paths } = tsConfigPaths.loadConfig()
const matchPath = tsConfigPaths.createMatchPath(absoluteBaseUrl, paths)

export function resolve(specifier, context, defaultResolver) {
	const mappedSpecifier = matchPath(specifier);
	if (mappedSpecifier) {
		specifier = pathToFileURL(mappedSpecifier) + '.ts';
	}
	return resolveTs(specifier, context, defaultResolver);
}