Function getHydratableHoistableCache

docs/index.js:17586–17615

(type, keyAttribute, ownerDocument)

}
var tagCaches = null;
function getHydratableHoistableCache(type, keyAttribute, ownerDocument) {
  if (null === tagCaches) {
    var cache = new Map();
    var caches = (tagCaches = new Map());
    caches.set(ownerDocument, cache);
  } else
    (caches = tagCaches),
      (cache = caches.get(ownerDocument)),
      cache || ((cache = new Map()), caches.set(ownerDocument, cache));
  if (cache.has(type)) return cache;
  cache.set(type, null);
  ownerDocument = ownerDocument.getElementsByTagName(type);
  for (caches = 0; caches < ownerDocument.length; caches++) {
    var node = ownerDocument[caches];
    if (
      !(
        node[internalHoistableMarker] ||
        node[internalInstanceKey] ||
        ("link" === type && "stylesheet" === node.getAttribute("rel"))
      ) &&
      "http://www.w3.org/2000/svg" !== node.namespaceURI
    ) {
      var nodeKey = node.getAttribute(keyAttribute) || "";
      nodeKey = type + nodeKey;
      var existing = cache.get(nodeKey);
      existing ? existing.push(node) : cache.set(nodeKey, [node]);
    }
  }
  return cache;
}
function mountHoistable(hoistableRoot, type, instance) {
  hoistableRoot = hoistableRoot.ownerDocument || hoistableRoot;
  hoistableRoot.head.insertBefore(