differences-between-two-objects.js

/**
 * @param {object} obj1
 * @param {object} obj2
 * @return {object}
 */
function objDiff(obj1, obj2) {
  if (obj1 === obj2) return {}
  if (
    (obj1 === null || obj2 === null) ||
    (typeof obj1 !== 'object' || typeof obj2 !== 'object') ||
    (Array.isArray(obj1) !== Array.isArray(obj2))
  ) return [obj1, obj2]

  const res = {}

  for (const key in obj1) {
    if (key in obj2) {
      const diff = objDiff(obj1[key], obj2[key])
      const keys = Object.keys(diff)

      if (keys.length > 0) {
        res[key] = diff
      }
    }
  }

  return res;
};