Function buildNode

packages/rrweb-snapshot/src/rebuild.ts:293–542

(
  n: serializedNodeWithId,
  options: {
    doc: Document;
    hackCss: boolean;
    cache: BuildCache;
  },
)

}

function buildNode(
  n: serializedNodeWithId,
  options: {
    doc: Document;
    hackCss: boolean;
    cache: BuildCache;
  },
): Node | null {
  const { doc, hackCss, cache } = options;
  switch (n.type) {
    case NodeType.Document:
      return doc.implementation.createDocument(null, '', null);
    case NodeType.DocumentType:
      return doc.implementation.createDocumentType(
        n.name || 'html',
        n.publicId,
        n.systemId,
      );
    case NodeType.Element: {
      const tagName = getTagName(n);
      let node: Element;
      if (n.isSVG) {
        node = doc.createElementNS('http://www.w3.org/2000/svg', tagName);
      } else {
        if (
          // If the tag name is a custom element name
          n.isCustom &&
          // If the browser supports custom elements
          doc.defaultView?.customElements &&
          // If the custom element hasn't been defined yet
          !doc.defaultView.customElements.get(n.tagName)
        )
          doc.defaultView.customElements.define(
            n.tagName,
            class extends doc.defaultView.HTMLElement {},
          );
        node = doc.createElement(tagName);
      }
      /**
       * Attribute names start with `rr_` are internal attributes added by rrweb.
       * They often overwrite other attributes on the element.
       * We need to parse them last so they can overwrite conflicting attributes.
       */
      const specialAttributes: { [key: string]: string | number } = {};
      for (const name in n.attributes) {
        if (!Object.prototype.hasOwnProperty.call(n.attributes, name)) {
          continue;
        }
        let value = n.attributes[name];
        if (
          tagName === 'option' &&
          name === 'selected' &&
          (value as legacyAttributes[typeof name]) === false
        ) {
          // legacy fix (TODO: if `value === false` can be generated for other attrs,
          // should we also omit those other attrs from build ?)
          continue;
        }