From 67da548b4828e4e7d5a10c38478c3656e1305bac Mon Sep 17 00:00:00 2001
From: Jun Pataleta <jun@moodle.com>
Date: Fri, 22 Oct 2021 20:50:44 +0800
Subject: [PATCH] MDL-72885 output: Add lang attribute for language menu items

---
 lib/classes/output/language_menu.php          | 22 +++++++++++++++++--
 .../user_action_menu_submenu_items.mustache   |  3 ++-
 lib/tests/output/language_menu_test.php       | 13 +++++++++--
 theme/boost/templates/language_menu.mustache  |  3 ++-
 4 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/lib/classes/output/language_menu.php b/lib/classes/output/language_menu.php
index 36384725a18..846362bbe5e 100644
--- a/lib/classes/output/language_menu.php
+++ b/lib/classes/output/language_menu.php
@@ -96,6 +96,14 @@ class language_menu implements \renderable, \templatable {
         // Add the lang picker if needed.
         foreach ($this->langs as $langtype => $langname) {
             $isactive = $langtype == $this->currentlang;
+            $attributes = [];
+            if (!$isactive) {
+                // Set the lang attribute for languages different from the page's current language.
+                $attributes[] = [
+                    'key' => 'lang',
+                    'value' => get_html_lang_attribute_value($langtype),
+                ];
+            }
             $node = [
                 'title' => $langname,
                 'text' => $langname,
@@ -103,6 +111,9 @@ class language_menu implements \renderable, \templatable {
                 'isactive' => $isactive,
                 'url' => $isactive ? new \moodle_url('#') : new \moodle_url($this->page->url, ['lang' => $langtype]),
             ];
+            if (!empty($attributes)) {
+                $node['attributes'] = $attributes;
+            }
 
             $nodes[] = $node;
 
@@ -135,8 +146,15 @@ class language_menu implements \renderable, \templatable {
         }
         $langmenu->set_menu_trigger($menuname);
         foreach ($languagedata['items'] as $node) {
-            $lang = new \action_menu_link_secondary($node['url'], null, $node['title'],
-                ['data-lang' => $node['url']->get_param('lang')]);
+            $langparam = $node['url']->get_param('lang');
+            $attributes = [];
+            if ($langparam) {
+                $attributes = [
+                    'data-lang' => $langparam,
+                    'lang' => $langparam,
+                ];
+            }
+            $lang = new \action_menu_link_secondary($node['url'], null, $node['title'], $attributes);
             $langmenu->add($lang);
         }
         return $langmenu->export_for_template($output);
diff --git a/lib/templates/user_action_menu_submenu_items.mustache b/lib/templates/user_action_menu_submenu_items.mustache
index 605ab867116..35a25e3eeea 100644
--- a/lib/templates/user_action_menu_submenu_items.mustache
+++ b/lib/templates/user_action_menu_submenu_items.mustache
@@ -41,7 +41,8 @@
 }}
 {{#items}}
     {{#link}}
-        <a href="{{{url}}}" class="dropdown-item pl-5" role="menuitem" tabindex="-1" {{#isactive}}aria-current="true"{{/isactive}}>
+        <a href="{{{url}}}" class="dropdown-item pl-5" role="menuitem" tabindex="-1" {{#isactive}}aria-current="true"{{/isactive}}
+            {{#attributes}}{{key}}="{{value}}" {{/attributes}}>
             {{text}}
         </a>
     {{/link}}
diff --git a/lib/tests/output/language_menu_test.php b/lib/tests/output/language_menu_test.php
index eccf12e974e..7587227f8f3 100644
--- a/lib/tests/output/language_menu_test.php
+++ b/lib/tests/output/language_menu_test.php
@@ -72,10 +72,19 @@ class language_menu_test extends \advanced_testcase {
             // Assert that the number of language menu items matches the number of the expected items.
             $this->assertEquals(count($expected['items']), count($response['items']));
             foreach ($expected['items'] as $expecteditem) {
+                $lang = $expecteditem['lang'];
                 // We need to manually generate the url key and its value in the expected item array as this cannot
                 // be done in the data provider due to the change of the state of $PAGE.
-                $expecteditem['url'] = $expecteditem['isactive'] ? new \moodle_url('#') :
-                    new \moodle_url($PAGE->url, ['lang' => $expecteditem['lang']]);
+                if ($expecteditem['isactive']) {
+                    $expecteditem['url'] = new \moodle_url('#');
+                } else {
+                    $expecteditem['url'] = new \moodle_url($PAGE->url, ['lang' => $lang]);
+                    // When the language menu item is not the current language, it will contain the lang attribute.
+                    $expecteditem['attributes'][] = [
+                        'key' => 'lang',
+                        'value' => $lang
+                    ];
+                }
                 // The lang value is only used to generate the url, so this key can be removed.
                 unset($expecteditem['lang']);
 
diff --git a/theme/boost/templates/language_menu.mustache b/theme/boost/templates/language_menu.mustache
index 305f8a85c63..b3f77d2d9e7 100644
--- a/theme/boost/templates/language_menu.mustache
+++ b/theme/boost/templates/language_menu.mustache
@@ -53,7 +53,8 @@
         <div role="menu" aria-labelledby="lang-menu-toggle" id="lang-action-menu" class="dropdown-menu dropdown-menu-right">
             {{#items}}
                 {{#link}}
-                    <a href="{{{url}}}" class="dropdown-item pl-5" role="menuitem" {{#isactive}}aria-current="true"{{/isactive}}>
+                    <a href="{{{url}}}" class="dropdown-item pl-5" role="menuitem" {{#isactive}}aria-current="true"{{/isactive}}
+                            {{#attributes}}{{key}}="{{value}}" {{/attributes}}>
                         {{text}}
                     </a>
                 {{/link}}