tsconfig paths to webpack

tsconfig-paths.mjs

import { dirname, resolve } from 'node:path';
import ts from 'typescript';

/** @typedef {Record<'compilerOptions', ts.server.protocol.CompilerOptions>} CompilerOptions */

const parsedConfig =
  /** @type {Record<'raw', CompilerOptions>} */
  (
    ts.getParsedCommandLineOfConfigFile('tsconfig.json', undefined, {
      ...ts.sys,
      onUnRecoverableConfigFileDiagnostic(diag) {
        throw new Error(`${diag.messageText}`);
      },
    })
  );

/**
 * Retrieves the paths defined in the `paths` section of the `tsconfig.json` configuration file.
 * @returns {ts.MapLike<string[]>} An object containing paths to various modules. An empty object if there is no `paths` section.
 * @example
 * ```
 * export default {
 *   resolve: {
 *     alias: tsconfigPaths(),
 *   },
 * }
 * ```
 *
 */
export function tsconfigPaths() {
  const res = /** @type {ts.MapLike<string[]>} */ (Object.create(null));
  const { paths } = parsedConfig.raw.compilerOptions;
  if (paths) {
    for (const k in paths) {
      const v = paths[k];
      res[k.endsWith('*') ? dirname(k) : k] = v.map((p) => {
        return resolve(process.cwd(), dirname(p));
      });
    }
  }
  return res;
}