Javascript Interview Question: Reverse a string

reverse-string.js

/*
 A few ways to reverse a string using JavaScript.
*/

//Most direct solution
function reverse(str) {
  return str.split('').reverse().join('');
}

//Example using the Array.reduce helper.
function reverse(str) {
  return str.split('').reduce((newStr, char) => char + newStr, '');  
}

//Example using recursion.
function reverse(str) {
  if (str.length <= 1) {
    return str;
  }
  
  return reverse(str.substr(1)) + str[0];
}

//Jest test case
test('It should reverse the string.', () => {
  expect(reverse('abc')).toEqual('cba');
});

//Try it
console.log(reverse('abc'));