A node.js function to find all files in a directory by given filter.

findFiles.js

const fs = require('fs');
const path = require('path');

function findFiles(startPath,filter,callback){
  if (!fs.existsSync(startPath)){
    console.log("Gosh, can't seem to find what you're looking for, my friend! Try a different startPath");
    return;
   }
   const files=fs.readdirSync(startPath);
   for (let currentFilePath of files) {
    const filename=path.join(startPath,currentFilePath);
    const stat = fs.lstatSync(filename);
    if (stat.isDirectory()){
      fromDir(filename,filter,callback);
    } 
    else if (filter.test(filename)) callback(filename);
  }
}

// Example: 
// let collectedFiles = [];

// findFiles('.',/\.html$|\.shtml$/,filename => {
//   collectedFiles.push(filename);
// });