Function isPlainObject

src/utils/isPlainObject.js:8–29

(obj)

 * @returns {boolean} True if the argument appears to be a plain object.
 */
export default function isPlainObject(obj) {
  if (!obj || typeof obj !== 'object') {
    return false;
  }

  const proto =
    typeof obj.constructor === 'function'
      ? Object.getPrototypeOf(obj)
      : Object.prototype;

  if (proto === null) {
    return true;
  }

  const constructor = proto.constructor;

  return (
    typeof constructor === 'function' &&
    constructor instanceof constructor &&
    fnToString(constructor) === fnToString(Object)
  );
}