fixDts.ts

import type { Plugin } from "rolldown";
import { format, type Options } from "prettier";

const prettyOptions: Options = {
  parser: "typescript",
  printWidth: 120,
};

/** @desc Fixes weird formatting in the .d.ts files generated by rolldown-plugin-dts v0.21 */
export const fixDtsPlugin = (): Plugin => ({
  name: "fix-dts-rolldown-plugin",
  generateBundle: async (_opt, bundle) => {
    for (const [name, file] of Object.entries(bundle)) {
      if (!(name.endsWith(".d.ts") && "code" in file)) continue;
      file.code = await format(
        file.code
          .replaceAll(/^\/\/#(end)?region[^\r\n]*/gm, "") // rm rolldown comments
          .replaceAll(/\n\s*\n/g, "\n"), // rm double newlines
        prettyOptions,
      );
    }
  },
});