Recursively rename all file extensions in a given directory from javascript to typescript

convertJsToTs.js

const { resolve } = require('path');
const { readdir, rename } = require('fs').promises;

const DIRECTORY = 'src';

async function* getFiles(dir) {
  const dirents = await readdir(dir, { withFileTypes: true });
  for (const dirent of dirents) {
    const res = resolve(dir, dirent.name);
    if (dirent.isDirectory()) {
      yield* getFiles(res);
    } else {
      yield res;
    }
  }
}

(async () => {
  for await (const originalFilePath of getFiles(DIRECTORY)) {
    const parts = originalFilePath.split('.');
    parts[parts.length - 1] = parts[parts.length - 1].replace(/js/, 'ts');
    
    const newFilePath = parts.join('.');
    await rename(originalFilePath, newFilePath);
  }
})()

Simply execute with node ./convertJsToJs.js