I am trying to fix this Eslint error:

Expected an assignment or function call an instead saw an expression

Any idea on how I can accommodate the code so that it doesn't give me that error in following sample code?

window.matchMedia || (window.matchMedia = function() {
 
  if (!styleMedia) {
    const style = document.createElement('style');

    const script = document.getElementsByTagName('script')[0];

    let info = null;

    style.type  = 'text/css';
    style.id    = 'matchmediajs-test';

    script.parentNode.insertBefore(style, script);

    info = ('getComputedStyle' in window) && window.getComputedStyle(style, null) || style.currentStyle;

    styleMedia = {
      matchMedium: function(media) {
        const text = '@media ' + media + '{ #matchmediajs-test { width: 1px; } }';

     
        if (style.styleSheet) {
          style.styleSheet.cssText = text;
        } else {
          style.textContent = text;
        }

        return info.width === '1px';
      },
    };
  }

  return function(media) {
    return {
      matches: styleMedia.matchMedium(media || 'all'),
      media: media || 'all',
    };
  };
}());

Any idea why I am getting this lint error?

Thank you