palindrome.js

const palindrome = (words) => {
  if (typeof words !== 'string') return 'provide a string or a phrase';
  const wordArray = words.replace(/([^\w])/g, '').split('');
  return checkPalindrome(wordArray);
}
function checkPalindrome(arrayOfChars) {
  if (!Array.isArray(arrayOfChars)) return 'please provide an array';
  if (arrayOfChars.join('') === arrayOfChars.reverse().join('')) return 'this is a palindrome';
  return 'this is not a palindrome';
}

console.log('fail: ', palindrome([]));
console.log('fail: ', palindrome(12));
console.log('fail: ', palindrome('12'));
console.log('fail: ', palindrome('popp'));
console.log('pass: ', palindrome('madam'));
console.log('pass: ', palindrome('pop'));
console.log('pass: ', palindrome('nurses run'));
console.log('pass: ', palindrome('peep'));