Validation input full name

June 25, 2022

There is a task: The field “First Name Last Name” can only consist of 2 words (first name and last name). Min length of each word is 3 characters, max 30. There is only 1 space between words.

The problem is that after the first word, when you put a space, it already returns true. Why? And how to check the 1 space in this input?

const validateInput = (value) => {
  const lengthValue = value.split(' ').length

  if (lengthValue !== 2) {
    return false
  } else {
    return value.split(' ').filter(el => el.length > 3 && el.length <= 30) ?
      value.search(/[A-Za-z]+(\s+[A-Za-z]+)?/gi) !== -1 ?
      true :
      false :
      ''
  }
}

>Solution :

Use trim to remove spaces from around the words before testing
No need for else after a return. Makes it easier to read too
Why are you testing the words in the name for whitespace? That only works if the user pasted a newline or a tab, since you split on space
You have a nested ternary, why would you return an empty string there?

Also please read this for the future falsehoods programmers believe about names

const re = /[A-Za-z]{3,30}/;
const validateInput = (value) => {
  const val = value.trim();
  if (val === "") return false;
  const arr =  value.split(' ');
  if (arr.length != 2) return false;
  const [firstName, lastName] = arr;
  return re.test(firstName) && re.test(lastName); // we could use .every here but you only have two
}
console.log(validateInput("Hans Anders"));
console.log(validateInput("Prince"));
console.log(validateInput("X Æ A-12"));
console.log(validateInput("   A    "));