fix handling of flat categories in browse view (#23395)

Author: cconard96

src/Glpi/Features/TreeBrowse.php

@@ -281,7 +281,7 @@ public static function getTreeCategoryList(string $itemtype, array $params): arr
                 }
             }
             if (($category['items_count'] > 0) || (in_array($category['id'], $parents))) {
-                $parents[] = $category[$cat_fk];
+                $parents[] = $category[$cat_fk] ?? 0;
                 $categories[] = $category;
             }
         }

tests/functional/UserTest.php

@@ -43,6 +43,7 @@
 use Profile_User;
 use Psr\Log\LogLevel;
 use User;
+use UserCategory;
 
 class UserTest extends DbTestCase
 {
@@ -2506,4 +2507,39 @@ public function testGetFromSSOAndRightRules()
         $this->assertEquals("0", $user->fields["_ldap_rules"]["rules_entities_rights"][0][0]); // entities_id
         $this->assertEquals($admin_profile_id, $user->fields["_ldap_rules"]["rules_entities_rights"][0][1]); // profiles_id
     }
+
+    /**
+     * The TreeBrowse list is available for users, but user categories are not hierarchical.
+     * This test ensures results can be fetched properly even for flat results.
+     * @return void
+     */
+    public function testGetTreeCategoryList()
+    {
+        $this->login();
+
+        $cat1 = $this->createItem(UserCategory::class, [
+            'name' => __FUNCTION__ . '_1',
+        ]);
+        $cat2 = $this->createItem(UserCategory::class, [
+            'name' => __FUNCTION__ . '_2',
+        ]);
+
+        $this->createItem(User::class, [
+            'name' => __FUNCTION__ . '_cat1',
+            'usercategories_id' => $cat1->getID(),
+        ]);
+        $this->createItem(User::class, [
+            'name' => __FUNCTION__ . '_cat2',
+            'usercategories_id' => $cat2->getID(),
+        ]);
+
+        $tree = User::getTreeCategoryList(User::class, [
+            'itemtype' => User::class,
+            'browse' => 1,
+            'export_all' => true,
+        ]);
+        $this->assertCount(3, $tree);
+        $this->assertStringStartsWith(__FUNCTION__ . '_1', $tree[1]['title']);
+        $this->assertStringStartsWith(__FUNCTION__ . '_2', $tree[0]['title']);
+    }
 }