docs: function mergeIntoWithNoDuplicateKeys(one, two) {
    !(one && two && typeof one === 'object' && typeof two === 'object') ? "development" !== 'production' ? invariant(false, 'mergeIntoWithNoDuplicateKeys(): Cannot merge non-objects.') : _prodInvariant('80') : void 0;
  
    for (var key in two) {
      if (two.hasOwnProperty(key)) {
        !(one[key] === undefined) ? "development" !== 'production' ? invariant(false, 'mergeIntoWithNoDuplicateKeys(): Tried to merge two objects with the same key: `%s`. This conflict may be due to a mixin; in particular, this may be caused by two getInitialState() or getDefaultProps() methods returning objects with clashing keys.', key) : _prodInvariant('81', key) : void 0;
        one[key] = two[key];
      }
    }
    return one;
  }