@e-group/utils/esm/groupBy/groupBy.js

eGroup team utils that share across projects.

export default function groupBy(xs, key) {
  return xs.reduce((rv, x) => {
    const v = key instanceof Function ? key(x) : x[key]; // Not use copy for better performance
    // eslint-disable-next-line no-param-reassign

    (rv[v] = rv[v] || []).push(x);
    return rv;
  }, {});
}