Method morph

www/js/_hyperscript.js:3534–3561

* Morph oldNode to match content. * @param {Element} oldNode - The existing DOM element to morph * @param {string|Element|DocumentFragment} content - The new content * @param {MorphCallbacks} [callbacks] - Optional lifecycle callbacks

(oldNode, content, callbacks = {})

     * @param {MorphCallbacks} [callbacks] - Optional lifecycle callbacks
     */
    morph(oldNode, content, callbacks = {}) {
      var fragment;
      if (typeof content === "string") {
        var temp = document.createElement("template");
        temp.innerHTML = content;
        fragment = temp.content;
      } else if (content instanceof DocumentFragment) {
        fragment = content;
      } else if (content instanceof Element) {
        fragment = document.createDocumentFragment();
        fragment.append(content.cloneNode(true));
      } else {
        throw new Error("morph requires an HTML string, element, or document fragment");
      }
      var newRoot = fragment.firstElementChild;
      if (newRoot && !newRoot.nextElementSibling && newRoot.tagName === oldNode.tagName) {
        _copyAttributes(oldNode, newRoot);
        fragment = newRoot;
      }
      var { persistentIds, idMap } = _createIdMaps(oldNode, fragment);
      var pantry = document.createElement("div");
      pantry.hidden = true;
      (document.body || oldNode.parentElement).after(pantry);
      var ctx = { target: oldNode, idMap, persistentIds, pantry, futureMatches: /* @__PURE__ */ new WeakSet(), callbacks };
      _morphChildren(ctx, oldNode, fragment);
      callbacks.beforeNodeRemoved?.(pantry);
      pantry.remove();
    }
  };
  function _morphChildren(ctx, oldParent, newParent, insertionPoint = null, endPoint = null) {
    if (oldParent instanceof HTMLTemplateElement && newParent instanceof HTMLTemplateElement) {