how to reverse a text js code example

Example 1: javascript string reverse

"this is a test string".split("").reverse().join("");
//"gnirts tset a si siht"

// Or
const reverse = str => [...str].reverse().join('');

// Or
const reverse = str => str.split('').reduce((rev, char)=> `${char}${rev}`, '');

// Or
const reverse = str => (str === '') ? '' : `${reverse(str.substr(1))}${str.charAt(0)}`;

// Example
reverse('hello world');     // 'dlrow olleh'

Example 2: javascript reverse string

function reverseString(str) {
  if (str === "")
    return "";
  else
    return reverseString(str.substr(1)) + str.charAt(0);
}
reverseString("hello");