From e671b1ff0b581bd5935fe407b788a8338a72c79d Mon Sep 17 00:00:00 2001
From: Jun Pataleta <jun@moodle.com>
Date: Fri, 21 Jun 2024 17:23:17 +0800
Subject: [PATCH] MDL-67683 blocks: Do not assign a complementary role for
 blocks

Blocks are contained in an <aside> which has a default ARIA role of
"complementary", a top-level landmark. So assigning a "complementary"
role for block instances is not needed. As blocks are already in a
<section> tag which has a default role of "region", there's no need
to override the ARIA role, unless specified by the block plugin.

Read more at:
https://www.w3.org/WAI/ARIA/apg/practices/landmark-regions/
---
 blocks/moodleblock.class.php         | 16 +++++++++-------
 lib/classes/output/core_renderer.php |  2 +-
 lib/templates/block.mustache         |  4 ++--
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/blocks/moodleblock.class.php b/blocks/moodleblock.class.php
index 44fcf568d03..1696b4730bd 100644
--- a/blocks/moodleblock.class.php
+++ b/blocks/moodleblock.class.php
@@ -446,8 +446,11 @@ class block_base {
         $attributes = array(
             'id' => 'inst' . $this->instance->id,
             'class' => 'block_' . $this->name() . ' block',
-            'role' => $this->get_aria_role()
         );
+        $ariarole = $this->get_aria_role();
+        if ($ariarole) {
+            $attributes['role'] = $ariarole;
+        }
         if ($this->hide_header()) {
             $attributes['class'] .= ' no-header';
         }
@@ -739,20 +742,19 @@ EOD;
      * a landmark child.
      *
      * Options are as follows:
+     *    - application
      *    - landmark
-     *      - application
-     *      - banner
-     *      - complementary
-     *      - contentinfo
      *      - form
-     *      - main
      *      - navigation
      *      - search
      *
+     * Please do not use top-level landmark roles such as 'banner', 'complementary', 'contentinfo', or 'main'. Read more at
+     * {@link https://www.w3.org/WAI/ARIA/apg/practices/landmark-regions/ ARIA Authoring Practices Guide - Landmark Regions}
+     *
      * @return string
      */
     public function get_aria_role() {
-        return 'complementary';
+        return 'region';
     }
 
     /**
diff --git a/lib/classes/output/core_renderer.php b/lib/classes/output/core_renderer.php
index ca2f8d18c47..592a1f72476 100644
--- a/lib/classes/output/core_renderer.php
+++ b/lib/classes/output/core_renderer.php
@@ -1504,7 +1504,7 @@ class core_renderer extends renderer_base {
         $context->skiptitle = strip_tags($bc->title);
         $context->showskiplink = !empty($context->skiptitle);
         $context->arialabel = $bc->arialabel;
-        $context->ariarole = !empty($bc->attributes['role']) ? $bc->attributes['role'] : 'complementary';
+        $context->ariarole = !empty($bc->attributes['role']) ? $bc->attributes['role'] : '';
         $context->class = $bc->attributes['class'];
         $context->type = $bc->attributes['data-block'];
         $context->title = $bc->title;
diff --git a/lib/templates/block.mustache b/lib/templates/block.mustache
index 8dfcb371571..ae9e6332860 100644
--- a/lib/templates/block.mustache
+++ b/lib/templates/block.mustache
@@ -7,7 +7,7 @@
         "class": "block block_html",
         "showskiplink": true,
         "type": "html",
-        "ariarole": "complementary",
+        "ariarole": "",
         "title": "Test block",
         "blockinstanceid": 1,
         "content": "<p>Hello block world!</p>"
@@ -22,7 +22,7 @@
 {{! Start Block Container }}
 <section id="{{id}}"
      class="{{#hidden}}hidden{{/hidden}} {{class}} {{#hascontrols}}block_with_controls{{/hascontrols}} card mb-3"
-     role="{{ariarole}}"
+     {{#ariarole}}role="{{.}}"{{/ariarole}}
      data-block="{{type}}"
      data-instance-id="{{blockinstanceid}}"
      {{#arialabel}}