--- /dev/null
+/**
+ * @file
+ * Attaches behaviors for Drupal's active link marking.
+ */
+
+(function (Drupal, drupalSettings) {
+ /**
+ * Append is-active class.
+ *
+ * The link is only active if its path corresponds to the current path, the
+ * language of the linked path is equal to the current language, and if the
+ * query parameters of the link equal those of the current request, since the
+ * same request with different query parameters may yield a different page
+ * (e.g. pagers, exposed View filters).
+ *
+ * Does not discriminate based on element type, so allows you to set the
+ * is-active class on any element: a, li…
+ *
+ * @type {Drupal~behavior}
+ */
+ Drupal.behaviors.activeLinks = {
+ attach(context) {
+ // Start by finding all potentially active links.
+ const path = drupalSettings.path;
+ const queryString = JSON.stringify(path.currentQuery);
+ const querySelector = path.currentQuery ? `[data-drupal-link-query='${queryString}']` : ':not([data-drupal-link-query])';
+ const originalSelectors = [`[data-drupal-link-system-path="${path.currentPath}"]`];
+ let selectors;
+
+ // If this is the front page, we have to check for the <front> path as
+ // well.
+ if (path.isFront) {
+ originalSelectors.push('[data-drupal-link-system-path="<front>"]');
+ }
+
+ // Add language filtering.
+ selectors = [].concat(
+ // Links without any hreflang attributes (most of them).
+ originalSelectors.map(selector => `${selector}:not([hreflang])`),
+ // Links with hreflang equals to the current language.
+ originalSelectors.map(selector => `${selector}[hreflang="${path.currentLanguage}"]`),
+ );
+
+ // Add query string selector for pagers, exposed filters.
+ selectors = selectors.map(current => current + querySelector);
+
+ // Query the DOM.
+ const activeLinks = context.querySelectorAll(selectors.join(','));
+ const il = activeLinks.length;
+ for (let i = 0; i < il; i++) {
+ activeLinks[i].classList.add('is-active');
+ }
+ },
+ detach(context, settings, trigger) {
+ if (trigger === 'unload') {
+ const activeLinks = context.querySelectorAll('[data-drupal-link-system-path].is-active');
+ const il = activeLinks.length;
+ for (let i = 0; i < il; i++) {
+ activeLinks[i].classList.remove('is-active');
+ }
+ }
+ },
+ };
+}(Drupal, drupalSettings));