code: function isActuallyCombinator(combinatorNode) {
    // `.foo  /*comment*/, .bar`
    //      ^^
    // If include comments, this spaces is a combinator, but it is not combinators.
    if (!/^\s+$/.test(combinatorNode.value)) {
      return true;
    }
  
    let next = combinatorNode.next();
  
    while (skipTest(next)) {
      next = next.next();
    }
  
    if (isNonTarget(next)) {
      return false;
    }
  
    let prev = combinatorNode.prev();
  
    while (skipTest(prev)) {
      prev = prev.prev();
    }
  
    if (isNonTarget(prev)) {
      return false;
    }
  
    return true;
  
    function skipTest(node) {
      if (!node) {
        return false;
      }
  
      if (node.type === "comment") {
        return true;
      }
  
      if (node.type === "combinator" && /^\s+$/.test(node.value)) {
        return true;
      }
  
      return false;
    }
  
    function isNonTarget(node) {
      if (!node) {
        return true;
      }
  
      if (node.type === "combinator" && !/^\s+$/.test(node.value)) {
        return true;
      }
  
      return false;
    }
  }
docs: Check whether is actually a combinator.
  @param {Node} combinatorNode The combinator node
  @returns {boolean} `true` if is actually a combinator.