removeScripts.js

import { attrsGroups } from './_collections.js';
import { detachNodeFromParent } from '../lib/xast.js';

export const name = 'removeScripts';
export const description = 'removes scripts (disabled by default)';

/** Union of all event attributes. */
const eventAttrs = [
  ...attrsGroups.animationEvent,
  ...attrsGroups.documentEvent,
  ...attrsGroups.documentElementEvent,
  ...attrsGroups.globalEvent,
  ...attrsGroups.graphicalEvent,
];

/**
 * Remove scripts.
 *
 * https://www.w3.org/TR/SVG11/script.html
 *
 * @author Patrick Klingemann
 * @type {import('./plugins-types.js').Plugin<'removeScripts'>}
 */
export const fn = () => {
  return {
    element: {
      enter: (node, parentNode) => {
        if (node.name === 'script') {
          detachNodeFromParent(node, parentNode);
          return;
        }

        for (const attr of eventAttrs) {
          if (node.attributes[attr] != null) {
            delete node.attributes[attr];
          }
        }
      },
      exit: (node, parentNode) => {
        if (node.name !== 'a') {
          return;
        }

        for (const attr of Object.keys(node.attributes)) {
          if (attr === 'href' || attr.endsWith(':href')) {
            if (
              node.attributes[attr] == null ||
              !node.attributes[attr].trimStart().startsWith('javascript:')
            ) {
              continue;
            }

            const index = parentNode.children.indexOf(node);
            const usefulChildren = node.children.filter(
              (child) => child.type !== 'text',
            );
            parentNode.children.splice(index, 1, ...usefulChildren);

            // TODO remove legacy parentNode in v4
            for (const child of node.children) {
              Object.defineProperty(child, 'parentNode', {
                writable: true,
                value: parentNode,
              });
            }
          }
        }
      },
    },
  };
};