text: var fs = require('fs');
  
  /**
   * @param {Array<string>} files
   * @param {Function} cb
   */
  
  function ensureFiles(files, cb) {
    var missingFiles = files.reduce(function(prev, filePath) {
      var fileFound = false;
  
      try {
        fileFound = fs.statSync(filePath).isFile();
      } catch (e) { }
  
      if (!fileFound) {
        prev.push(filePath + ' Not Found');
      }
  
      return prev;
    }, []);
  
    if (missingFiles.length) {
      var err = new Error('Missing Required Files\n' + missingFiles.join('\n'));
    }
  
    if (cb) {
      cb(err);
    } else if (err) {
      throw err;
    }
  }
  
  module.exports = ensureFiles;