constructor(partInfo) {
      var _a;
      super(partInfo);
      if (partInfo.type !== _directive.PartType.ATTRIBUTE || partInfo.name !== 'style' || ((_a = partInfo.strings) === null || _a === void 0 ? void 0 : _a.length) > 2) {
        throw new Error('The `styleMap` directive must be used in the `style` attribute ' + 'and must be the only part in the attribute.');
      }
    }
This is the original style-map.js directive from lit-html 2 with the only difference that "render" is not called even for the first rendering (update is used instead)