getNonDuplicateItems

/**
 * @param {Array<string|number>} employeeList
 * @param {Array<string|number>} aipEmployeeList
 */
const getNonDuplicateItems = (employeeList, aipEmployeeList) => {
  const resultList = new Set();
  if (!employeeList.length) return [];
  if (!aipEmployeeList.length) return employeeList;

  employeeList.filter((value) => {
    const isDuplicate = aipEmployeeList.indexOf(value) > -1;
    if (!isDuplicate) resultList.add(value);
  });
  return [...resultList];
};

console.log("=====case 1");
let a = ["a", "b", "c"];
let b = ["a", "b", "c", "d"];
console.log(getNonDuplicateItems(a, b));
console.log("====case 2");
a = ["a", "b", "c", "d"];
b = ["a", "b", "c"];
console.log(getNonDuplicateItems(a, b));
console.log("====case 3");
a = ["a", "b", "c", "d", "d", "d"];
b = ["a", "b", "c", "88"];
console.log(getNonDuplicateItems(a, b));
console.log("====case 4");
a = ["a", "b", "c"];
b = ["a", "b", "c"];
console.log(getNonDuplicateItems(a, b));
console.log("====case 5");
a = [];
b = ["a", "b", "c"];
console.log(getNonDuplicateItems(a, b));
console.log("====case 6");
a = ["a", "b", "c"];
b = [];
console.log(getNonDuplicateItems(a, b));