https://www.mobilitycairo.com/core/misc/active-link.js?v=10.6.16

1/**
2 * @file
3 * Attaches behaviors for Drupal's active link marking.
4 */
5
6(function (Drupal, drupalSettings) {
7  /**
8   * Append is-active class.
9   *
10   * The link is only active if its path corresponds to the current path, the
11   * language of the linked path is equal to the current language, and if the
12   * query parameters of the link equal those of the current request, since the
13   * same request with different query parameters may yield a different page
14   * (e.g. pagers, exposed View filters).
15   *
16   * Does not discriminate based on element type, so allows you to set the
17   * is-active class on any element: a, li…
18   *
19   * @type {Drupal~behavior}
20   */
21  Drupal.behaviors.activeLinks = {
22    attach(context) {
23      // Start by finding all potentially active links.
24      const path = drupalSettings.path;
25      const queryString = JSON.stringify(path.currentQuery);
26      const querySelector = queryString
27        ? `[data-drupal-link-query="${CSS.escape(queryString)}"]`
28        : ':not([data-drupal-link-query])';
29      const originalSelectors = [
30        `[data-drupal-link-system-path="${CSS.escape(path.currentPath)}"]`,
31      ];
32      let selectors;
33
34      // If this is the front page, we have to check for the <front> path as
35      // well.
36      if (path.isFront) {
37        originalSelectors.push('[data-drupal-link-system-path="<front>"]');
38      }
39
40      // Add language filtering.
41      selectors = [].concat(
42        // Links without any hreflang attributes (most of them).
43        originalSelectors.map((selector) => `${selector}:not([hreflang])`),
44        // Links with hreflang equals to the current language.
45        originalSelectors.map(
46          (selector) => `${selector}[hreflang="${path.currentLanguage}"]`,
47        ),
48      );
49
50      // Add query string selector for pagers, exposed filters.
51      selectors = selectors.map((current) => current + querySelector);
52
53      // Query the DOM.
54      const activeLinks = context.querySelectorAll(selectors.join(','));
55      const il = activeLinks.length;
56      for (let i = 0; i < il; i++) {
57        activeLinks[i].classList.add('is-active');
58        activeLinks[i].setAttribute('aria-current', 'page');
59      }
60    },
61    detach(context, settings, trigger) {
62      if (trigger === 'unload') {
63        const activeLinks = context.querySelectorAll(
64          '[data-drupal-link-system-path].is-active',
65        );
66        const il = activeLinks.length;
67        for (let i = 0; i < il; i++) {
68          activeLinks[i].classList.remove('is-active');
69          activeLinks[i].removeAttribute('aria-current');
70        }
71      }
72    },
73  };
74})(Drupal, drupalSettings);