JSFiddle - React, Tailwind, and code Playground

by aliaksej

JavaScript

function yearValidator(isMandatory, value, callback) {
  var isCheckRequired = isMandatory || !!value || value === 0;

  if (!isCheckRequired) {
    callback(true);
    return;
  }

  var isValidInteger = commonValidators.nonNegativeInteger(isMandatory)(value);

  if (!isValidInteger || String(value).length !== 4) {
      callback(false);
      return;
  }

  yearService.getYears()
    .then(function (years) {
        return years.some(function (year) {
            return year === value;
        });
    })
    .then(function(isValidYear) {
        callback(isValidYear)
    });// catch here??

}