List all files in a directory in Node.js recursively in a synchronous fashion

walksync.js

const fs = require('fs');
// List all files in a directory in Node.js recursively in a synchronous fashion
const walkSync = function(dir, filelist,ignoreList) {
  if(!dir.endsWith('/')){
    dir+='/';
  }
  const files = fs.readdirSync(dir);
  filelist = filelist || [];
  ignoreList = ignoreList || [];
  files.forEach(function(file) {
    if (fs.statSync(dir + file).isDirectory()) {
      filelist = walkSync(dir + file + '/', filelist,ignoreList);
    }
    else {
      if(!ignoreList.includes(file)){
        filelist.push(dir+file);
      }
      
    }
  });
  return filelist;
};