Method _insert

lib/jsdom/living/nodes/Node-impl.js:781–877

(nodeImpl, childImpl, suppressObservers)

  // https://dom.spec.whatwg.org/#concept-node-insert
  _insert(nodeImpl, childImpl, suppressObservers) {
    const count = nodeImpl.nodeType === NODE_TYPE.DOCUMENT_FRAGMENT_NODE ?
        domSymbolTree.childrenCount(nodeImpl) :
        1;

    if (childImpl) {
      const childIndex = domSymbolTree.index(childImpl);

      for (const range of this._liveRanges()) {
        const { _start, _end } = range;

        if (_start.offset > childIndex) {
          range._setLiveRangeStart(this, _start.offset + count);
        }

        if (_end.offset > childIndex) {
          range._setLiveRangeEnd(this, _end.offset + count);
        }
      }
    }

    const nodesImpl = nodeImpl.nodeType === NODE_TYPE.DOCUMENT_FRAGMENT_NODE ?
      domSymbolTree.childrenToArray(nodeImpl) :
      [nodeImpl];

    if (nodeImpl.nodeType === NODE_TYPE.DOCUMENT_FRAGMENT_NODE) {
      let grandChildImpl;
      while ((grandChildImpl = domSymbolTree.firstChild(nodeImpl))) {
        nodeImpl._remove(grandChildImpl, true);
      }
    }

    if (nodeImpl.nodeType === NODE_TYPE.DOCUMENT_FRAGMENT_NODE) {
      queueTreeMutationRecord(nodeImpl, [], nodesImpl, null, null);
    }

    const previousChildImpl = childImpl ?
      domSymbolTree.previousSibling(childImpl) :
      domSymbolTree.lastChild(this);

    let isConnected;

    for (const node of nodesImpl) {
      if (!childImpl) {
        domSymbolTree.appendChild(this, node);
      } else {
        domSymbolTree.insertBefore(childImpl, node);
      }

      if (
        (this.nodeType === NODE_TYPE.ELEMENT_NODE && this._shadowRoot !== null) &&
        (node.nodeType === NODE_TYPE.ELEMENT_NODE || node.nodeType === NODE_TYPE.TEXT_NODE)
      ) {
        assignSlot(node);
      }

      this._modified();