code: function baseKeysIn(object) {
    if (!isObject(object)) {
      return nativeKeysIn(object);
    }
    var isProto = isPrototype(object),
        result = [];
  
    for (var key in object) {
      if (!(key == 'constructor' && (isProto || !hasOwnProperty$b.call(object, key)))) {
        result.push(key);
      }
    }
    return result;
  }
docs: The base implementation of `_.keysIn` which doesn't treat sparse arrays as dense.
  
  @private
  @param {Object} object The object to query.
  @returns {Array} Returns the array of property names.