tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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AriaQueryHandler.ts (2640B)

      1 /**
      2 * @license
      3 * Copyright 2020 Google Inc.
      4 * SPDX-License-Identifier: Apache-2.0
      5 */
      6 
      7 import type {ElementHandle} from '../api/ElementHandle.js';
      8 import {QueryHandler, type QuerySelector} from '../common/QueryHandler.js';
      9 import type {AwaitableIterable} from '../common/types.js';
     10 import {assert} from '../util/assert.js';
     11 import {AsyncIterableUtil} from '../util/AsyncIterableUtil.js';
     12 
     13 interface ARIASelector {
     14  name?: string;
     15  role?: string;
     16 }
     17 
     18 const isKnownAttribute = (
     19  attribute: string,
     20 ): attribute is keyof ARIASelector => {
     21  return ['name', 'role'].includes(attribute);
     22 };
     23 
     24 /**
     25 * The selectors consist of an accessible name to query for and optionally
     26 * further aria attributes on the form `[<attribute>=<value>]`.
     27 * Currently, we only support the `name` and `role` attribute.
     28 * The following examples showcase how the syntax works wrt. querying:
     29 *
     30 * - 'title[role="heading"]' queries for elements with name 'title' and role 'heading'.
     31 * - '[role="image"]' queries for elements with role 'image' and any name.
     32 * - 'label' queries for elements with name 'label' and any role.
     33 * - '[name=""][role="button"]' queries for elements with no name and role 'button'.
     34 */
     35 const ATTRIBUTE_REGEXP =
     36  /\[\s*(?<attribute>\w+)\s*=\s*(?<quote>"|')(?<value>\\.|.*?(?=\k<quote>))\k<quote>\s*\]/g;
     37 const parseARIASelector = (selector: string): ARIASelector => {
     38  if (selector.length > 10_000) {
     39    throw new Error(`Selector ${selector} is too long`);
     40  }
     41 
     42  const queryOptions: ARIASelector = {};
     43  const defaultName = selector.replace(
     44    ATTRIBUTE_REGEXP,
     45    (_, attribute, __, value) => {
     46      assert(
     47        isKnownAttribute(attribute),
     48        `Unknown aria attribute "${attribute}" in selector`,
     49      );
     50      queryOptions[attribute] = value;
     51      return '';
     52    },
     53  );
     54  if (defaultName && !queryOptions.name) {
     55    queryOptions.name = defaultName;
     56  }
     57  return queryOptions;
     58 };
     59 
     60 /**
     61 * @internal
     62 */
     63 export class ARIAQueryHandler extends QueryHandler {
     64  static override querySelector: QuerySelector = async (
     65    node,
     66    selector,
     67    {ariaQuerySelector},
     68  ) => {
     69    return await ariaQuerySelector(node, selector);
     70  };
     71 
     72  static override async *queryAll(
     73    element: ElementHandle<Node>,
     74    selector: string,
     75  ): AwaitableIterable<ElementHandle<Node>> {
     76    const {name, role} = parseARIASelector(selector);
     77    yield* element.queryAXTree(name, role);
     78  }
     79 
     80  static override queryOne = async (
     81    element: ElementHandle<Node>,
     82    selector: string,
     83  ): Promise<ElementHandle<Node> | null> => {
     84    return (
     85      (await AsyncIterableUtil.first(this.queryAll(element, selector))) ?? null
     86    );
     87  };
     88 }