[BUGFIX] Fix open pageTree status

To determine the opened page branch, the uc path must be
BackendComponents.States.Pagetree.stateHash
instead of browseTrees.browsePages.

The configuration must also contain the following structure

[
  1_1234 => 1,
  1_3456 => 1
]

instead of

[
  1 => [
     1234,
     3456
  ]
]

Otherwise the page won't be expanded properly.

Resolves: #90985
Releases: master, 10.4
Change-Id: I63fb967c3d47286f24e4e469c4947a3c09047605
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/64109
Tested-by: core-ci <typo3@b13.com>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Benni Mack <benni@typo3.org>

typo3/sysext/backend/Classes/Utility/BackendUtility.php

@@ -501,13 +501,14 @@ public static function openPageTree($pid, $clearExpansion)
         if ($clearExpansion) {
             $expandedPages = [];
         } else {
-            $expandedPages = json_decode($beUser->uc['browseTrees']['browsePages'], true);
+            $expandedPages = $beUser->uc['BackendComponents']['States']['Pagetree']['stateHash'];
         }
         // Get rootline:
         $rL = self::BEgetRootLine($pid);
         // First, find out what mount index to use (if more than one DB mount exists):
         $mountIndex = 0;
-        $mountKeys = array_flip($beUser->returnWebmounts());
+        $mountKeys = $beUser->returnWebmounts();
+
         foreach ($rL as $rLDat) {
             if (isset($mountKeys[$rLDat['uid']])) {
                 $mountIndex = $mountKeys[$rLDat['uid']];
@@ -516,10 +517,10 @@ public static function openPageTree($pid, $clearExpansion)
         }
         // Traverse rootline and open paths:
         foreach ($rL as $rLDat) {
-            $expandedPages[$mountIndex][$rLDat['uid']] = 1;
+            $expandedPages[$mountIndex . '_' . $rLDat['uid']] = '1';
         }
         // Write back:
-        $beUser->uc['browseTrees']['browsePages'] = json_encode($expandedPages);
+        $beUser->uc['BackendComponents']['States']['Pagetree']['stateHash'] = $expandedPages;
         $beUser->writeUC();
     }
 

typo3/sysext/backend/Tests/Functional/Utility/BackendUtilityTest.php

@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+namespace TYPO3\CMS\Backend\Tests\Functional\Utility;
+
+use TYPO3\CMS\Backend\Utility\BackendUtility;
+use TYPO3\CMS\Core\Authentication\BackendUserAuthentication;
+use TYPO3\TestingFramework\Core\Functional\FunctionalTestCase;
+
+class BackendUtilityTest extends FunctionalTestCase
+{
+    public function setUp(): void
+    {
+        parent::setUp();
+        $this->importDataSet('PACKAGE:typo3/testing-framework/Resources/Core/Functional/Fixtures/pages.xml');
+        $this->setUpBackendUserFromFixture(1);
+    }
+
+    /**
+     * @test
+     */
+    public function givenPageIdCanBeExpanded(): void
+    {
+        $backendUser = $this->getBackendUser();
+        $backendUser->groupData['webmounts'] = '1';
+
+        BackendUtility::openPageTree(5, false);
+
+        $expectedSiteHash = [
+            '1_5' => '1',
+            '1_1' => '1',
+            '1_0' => '1'
+        ];
+        $actualSiteHash = $backendUser->uc['BackendComponents']['States']['Pagetree']['stateHash'];
+        self::assertSame($expectedSiteHash, $actualSiteHash);
+    }
+
+    /**
+     * @test
+     */
+    public function otherBranchesCanBeClosedWhenOpeningPage(): void
+    {
+        $backendUser = $this->getBackendUser();
+        $backendUser->groupData['webmounts'] = '1';
+
+        BackendUtility::openPageTree(5, false);
+        BackendUtility::openPageTree(4, true);
+
+        //the complete branch of uid => 5 should be closed here
+        $expectedSiteHash = [
+            '1_4' => '1',
+            '1_3' => '1',
+            '1_2' => '1',
+            '1_1' => '1',
+            '1_0' => '1'
+        ];
+        $actualSiteHash = $backendUser->uc['BackendComponents']['States']['Pagetree']['stateHash'];
+        self::assertSame($expectedSiteHash, $actualSiteHash);
+    }
+
+    private function getBackendUser(): BackendUserAuthentication
+    {
+        return $GLOBALS['BE_USER'];
+    }
+}