code: public static String directiveToTagName(String directiveClassName) {
      // Drop "Component" at the end of the class name
      directiveClassName = directiveClassName.replaceAll("Directive$", "");
      // Convert from CamelCase to kebab-case
      return CaseFormat.UPPER_CAMEL.to(CaseFormat.LOWER_HYPHEN, directiveClassName).toLowerCase();
    }
docs: Return the default name to register a directive based on it's class name The name of the tag is
  the name of the component converted to kebab-case If the component class ends with "Directive",
  this part is ignored
  
  @param directiveClassName The class name of the {@link VueDirective}
  @return The name of the directive as kebab case