blog/src/plugins/remark-directive-rehype.js

// biome-ignore lint/suspicious/noShadowRestrictedNames: <explanation>
import { h } from 'hastscript'
import { visit } from 'unist-util-visit'

export function parseDirectiveNode() {
  return (tree, _data) => {
    visit(tree, (node) => {
      if (
        node.type === 'containerDirective'
        || node.type === 'leafDirective'
        || node.type === 'textDirective'
      ) {
        const data = node.data || (node.data = {})
        node.attributes = node.attributes || {}
        if (
          node.children.length > 0
          && node.children[0].data
          && node.children[0].data.directiveLabel
        ) {
          // Add a flag to the node to indicate that it has a directive label
          node.attributes['has-directive-label'] = true
        }
        const hast = h(node.name, node.attributes)

        data.hName = hast.tagName
        data.hProperties = hast.properties
      }
    })
  }
}