How can we make a difference between "1" and 1 ? ("1" !== 1)

Question

I'm trying to make a function who want to say :

if ("1") false;
if (1) true;

i have try isInteger(), typeOf, isNaN(), etc ... But i can't find a solution ...

it's for my validator in node.js, i use "yup".

here an example :

const isNumber = yup
  .number()
  .positive()
  .test('number', 'verify number', (val) => {
    if (typeof val === 'number') {
      return true;
    }
    return false;
  })
  .required();