htmlEntities is not defined

function convertHTML(str) {
      // Use Object Lookup to declare as many HTML entities as needed.
// Try to add var before htmlEntities declaration to enable codes passed!
      htmlEntities={
        '&':'&',
        '<':'&lt;',
        '>':'&gt;',
        '"':'&quot;',
        '\'':"&apos;"
      };
      //Use map function to return a filtered str with all entities changed automatically.
      return str.split('').map(entity => htmlEntities[entity] || entity).join('');
    }

    // test here
    convertHTML("Dolce & Gabbana");



Add var before htmlEntities for codes to pass.

var indeed passes test,. but const is more accurate.