toFlatObject = (sourceObj, destObj, filter, propFilter) => {
  let props;
  let i;
  let prop;
  const merged = {};

  destObj = destObj || {};
  // eslint-disable-next-line no-eq-null,eqeqeq
  if (sourceObj == null) return destObj;

  do {
    props = Object.getOwnPropertyNames(sourceObj);
    i = props.length;
    while (i-- > 0) {
      prop = props[i];
      if ((!propFilter || propFilter(prop, sourceObj, destObj)) && !merged[prop]) {
        destObj[prop] = sourceObj[prop];
        merged[prop] = true;
      }
    }
    sourceObj = filter !== false && getPrototypeOf(sourceObj);
  } while (sourceObj && (!filter || filter(sourceObj, destObj)) && sourceObj !== Object.prototype);

  return destObj;
}
Resolve object with deep prototype chain to a flat object
@param {Object} sourceObj source object
@param {Object} [destObj]
@param {Function|Boolean} [filter]
@param {Function} [propFilter]

@returns {Object}