strong-map/lib/utils/fn.js

[](https://img.shields.io/npm/l/strong-map.svg) [](https://travis-ci.org/jorma16/strong-map) [![Coverage Status](https://cove

function equals(a, b) {
  if (a === b) {
    return true;
  }

  if (a instanceof Date && b instanceof Date) {
    return a.getTime() === b.getTime();
  }

  if (!a || !b || (typeof a !== 'object' && typeof b !== 'object')) {
    return a === b;
  }

  if (a === null || a === undefined || b === null || b === undefined) {
    return false;
  }

  if (a.prototype !== b.prototype) {
    return false;
  }

  const keys = Object.keys(a);
  if (keys.length !== Object.keys(b).length) {
    return false;
  }

  return keys.every((k) => equals(a[k], b[k]));
}

module.exports = { equals };