old-web/app/helpers/email.js

const isValidEmail = email => {
  const simpleEmailRegex = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
  return email && email.length < 250 && simpleEmailRegex.test(email);
};

module.exports = {
  isValidEmail
};