How to use the fela-utils.isNestedSelector function in fela-utils

function validateStyleObject(
  style: Object,
  logInvalid: boolean,
  deleteInvalid: boolean
): void {
  for (const property in style) {
    const value = style[property]

    if (isPlainObject(value)) {
      if (isNestedSelector(property) || isMediaQuery(property)) {
        validateStyleObject(value, logInvalid, deleteInvalid)
      } else {
        if (deleteInvalid) {
          delete style[property]
        }
        if (logInvalid) {
          console.error(
            `${deleteInvalid
              ? '[Deleted] '
              : ' '}Invalid nested property. Only use nested media queries, pseudo classes, child selectors or &-combinators.
              Maybe you forgot to add a plugin that resolves "${property}".`,
            {
              property,
              value,
            }
          )

(ruleset, value, property) => {
        if (isPlainObject(value)) {
          if (isNestedSelector(property)) {
            renderer._renderStyleToCache(
              className,
              value,
              pseudo + normalizeNestedProperty(property),
              media,
              support
            )
          } else if (isMediaQuery(property)) {
            const combinedMediaQuery = generateCombinedMediaQuery(
              media,
              property.slice(6).trim()
            )

            renderer._renderStyleToCache(
              className,
              value,

_renderStyleToClassNames(
      { _className, ...style }: Object,
      pseudo: string = '',
      media: string = '',
      support: string = ''
    ): string {
      let classNames = _className ? ` ${_className}` : ''

      for (const property in style) {
        const value = style[property]

        if (isPlainObject(value)) {
          if (isNestedSelector(property)) {
            classNames += renderer._renderStyleToClassNames(
              value,
              pseudo + normalizeNestedProperty(property),
              media,
              support
            )
          } else if (isMediaQuery(property)) {
            const combinedMediaQuery = generateCombinedMediaQuery(
              media,
              property.slice(6).trim()
            )
            classNames += renderer._renderStyleToClassNames(
              value,
              pseudo,
              combinedMediaQuery,
              support