From 7a5d5cdd09a301c965b44651df77f6efde211341 Mon Sep 17 00:00:00 2001
From: Alex Pott <alex.a.pott@googlemail.com>
Date: Sat, 16 Oct 2021 17:09:57 +0100
Subject: [PATCH] Issue #3227370 by pfrenssen: Toolbar menu theme override
 omits the 'menu_name' variable

(cherry picked from commit 117db6f91b7272e63d13f48bacd5b8ff0a42929c)
---
 .../tests/modules/toolbar_test/toolbar_test.module    | 11 +++++++++++
 core/modules/toolbar/toolbar.module                   |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/core/modules/toolbar/tests/modules/toolbar_test/toolbar_test.module b/core/modules/toolbar/tests/modules/toolbar_test/toolbar_test.module
index 1f919a1e0b3..cbc014054d3 100644
--- a/core/modules/toolbar/tests/modules/toolbar_test/toolbar_test.module
+++ b/core/modules/toolbar/tests/modules/toolbar_test/toolbar_test.module
@@ -48,3 +48,14 @@ function toolbar_test_toolbar() {
 
   return $items;
 }
+
+/**
+ * Implements hook_preprocess_HOOK().
+ */
+function toolbar_test_preprocess_menu(&$variables) {
+  // All the standard hook_theme variables should be populated when the
+  // Toolbar module is rendering a menu.
+  foreach (['menu_name', 'items', 'attributes'] as $variable) {
+    $variables[$variable];
+  }
+}
diff --git a/core/modules/toolbar/toolbar.module b/core/modules/toolbar/toolbar.module
index 483a30b76ae..5451dcb7515 100644
--- a/core/modules/toolbar/toolbar.module
+++ b/core/modules/toolbar/toolbar.module
@@ -41,7 +41,7 @@ function toolbar_theme($existing, $type, $theme, $path) {
   ];
   $items['menu__toolbar'] = [
     'base hook' => 'menu',
-    'variables' => ['items' => [], 'attributes' => []],
+    'variables' => ['menu_name' => NULL, 'items' => [], 'attributes' => []],
   ];
 
   return $items;