js array to object with keys

const convertArrayToObject = (array, key) =>
  array.reduce(
    (obj, item) => ({
      ...obj,
      [item[key]]: item
    }),
    {}
  );
const arr = ['a','b','c'];
const res = arr.reduce((a,b)=> (a[b]='',a),{});
console.log(res)