first commit

typo3/sysext/beuser/Classes/ViewHelpers/ArrayElementViewHelper.php

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+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Beuser\Exception;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+use TYPO3Fluid\Fluid\Core\ViewHelper\Traits\CompileWithRenderStatic;
+
+/**
+ * Get a value from an array by given key.
+ * @internal
+ */
+class ArrayElementViewHelper extends AbstractViewHelper
+{
+    use CompileWithRenderStatic;
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        $this->registerArgument('array', 'array', 'Array to search in', true);
+        $this->registerArgument('key', 'string', 'Key to return its value', true);
+        $this->registerArgument('subKey', 'string', 'If result of key access is an array, subkey can be used to fetch an element from this again', false, '');
+    }
+
+    /**
+     * Return array element by key. Accessed values must be scalar (string, int, float or double)
+     *
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     * @throws Exception
+     * @return string
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $array = $arguments['array'];
+        $key = $arguments['key'];
+        $subKey = $arguments['subKey'];
+        $result = '';
+        if (is_array($array) && isset($array[$key])) {
+            $result = $array[$key];
+            if (is_array($result) && $subKey && isset($result[$subKey])) {
+                $result = $result[$subKey];
+            }
+        }
+        if (!is_scalar($result)) {
+            throw new Exception('Only scalar return values (string, int, float or double) are supported.', 1382284105);
+        }
+        return $result;
+    }
+}

typo3/sysext/beuser/Classes/ViewHelpers/Display/PagesViewHelper.php

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+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers\Display;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Database\Connection;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+use TYPO3Fluid\Fluid\Core\ViewHelper\Traits\CompileWithRenderStatic;
+
+/**
+ * Converts comma separated list of pages uids to html unordered list (<ul>) with speaking titles
+ * @internal
+ */
+class PagesViewHelper extends AbstractViewHelper
+{
+    use CompileWithRenderStatic;
+
+    /**
+     * As this ViewHelper renders HTML, the output must not be escaped.
+     *
+     * @var bool
+     */
+    protected $escapeOutput = false;
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        $this->registerArgument('uids', 'string', '', false, '');
+    }
+
+    /**
+     * Render unordered list for pages
+     *
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     *
+     * @return string
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $uids = $arguments['uids'];
+        if (!$uids) {
+            return '';
+        }
+
+        $content = '';
+
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('pages');
+        $queryBuilder->getRestrictions()->removeAll();
+
+        $res = $queryBuilder
+            ->select('uid', 'title')
+            ->from('pages')
+            ->where(
+                $queryBuilder->expr()->in(
+                    'uid',
+                    $queryBuilder->createNamedParameter(
+                        GeneralUtility::intExplode(',', $uids),
+                        Connection::PARAM_INT_ARRAY
+                    )
+                )
+            )
+            ->orderBy('uid', 'ASC')
+            ->execute();
+
+        while ($row = $res->fetch()) {
+            $content .= '<li>' . htmlspecialchars($row['title']) . ' [' . htmlspecialchars($row['uid']) . ']</li>';
+        }
+        return '<ul>' . $content . '</ul>';
+    }
+}

typo3/sysext/beuser/Classes/ViewHelpers/Display/SysFileMountsViewHelper.php

@@ -0,0 +1,88 @@
+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers\Display;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Database\Connection;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+use TYPO3Fluid\Fluid\Core\ViewHelper\Traits\CompileWithRenderStatic;
+
+/**
+ * Converts comma separated list of sys_filemounts uids to html unordered list (<ul>) with speaking titles
+ * @internal
+ */
+class SysFileMountsViewHelper extends AbstractViewHelper
+{
+    use CompileWithRenderStatic;
+
+    /**
+     * As this ViewHelper renders HTML, the output must not be escaped.
+     *
+     * @var bool
+     */
+    protected $escapeOutput = false;
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        $this->registerArgument('uids', 'string', '', false, '');
+    }
+
+    /**
+     * Render unordered list for sys_filemounts
+     *
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     *
+     * @return string
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $uids = $arguments['uids'];
+        if (!$uids) {
+            return '';
+        }
+
+        $content = '';
+
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('sys_filemounts');
+        $queryBuilder->getRestrictions()->removeAll();
+
+        $res = $queryBuilder
+            ->select('uid', 'title')
+            ->from('sys_filemounts')
+            ->where(
+                $queryBuilder->expr()->in(
+                    'uid',
+                    $queryBuilder->createNamedParameter(
+                        GeneralUtility::intExplode(',', $uids),
+                        Connection::PARAM_INT_ARRAY
+                    )
+                )
+            )
+            ->orderBy('title', 'ASC')
+            ->execute();
+
+        while ($row = $res->fetch()) {
+            $content .= '<li>' . htmlspecialchars($row['title']) . ' [' . htmlspecialchars($row['uid']) . ']</li>';
+        }
+        return '<ul>' . $content . '</ul>';
+    }
+}

typo3/sysext/beuser/Classes/ViewHelpers/Display/SysLanguageViewHelper.php

@@ -0,0 +1,88 @@
+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers\Display;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Database\Connection;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+use TYPO3Fluid\Fluid\Core\ViewHelper\Traits\CompileWithRenderStatic;
+
+/**
+ * Converts comma separated list of sys_language uids to html unordered list (<ul>) with speaking titles
+ * @internal
+ */
+class SysLanguageViewHelper extends AbstractViewHelper
+{
+    use CompileWithRenderStatic;
+
+    /**
+     * As this ViewHelper renders HTML, the output must not be escaped.
+     *
+     * @var bool
+     */
+    protected $escapeOutput = false;
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        $this->registerArgument('uids', 'string', '', false, '');
+    }
+
+    /**
+     * Render unordered list for sys_language
+     *
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     *
+     * @return string
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $uids = $arguments['uids'];
+        if (!$uids) {
+            return '';
+        }
+
+        $content = '';
+
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('sys_language');
+        $queryBuilder->getRestrictions()->removeAll();
+
+        $res = $queryBuilder
+            ->select('uid', 'title', 'flag')
+            ->from('sys_language')
+            ->where(
+                $queryBuilder->expr()->in(
+                    'uid',
+                    $queryBuilder->createNamedParameter(
+                        GeneralUtility::intExplode(',', $uids),
+                        Connection::PARAM_INT_ARRAY
+                    )
+                )
+            )
+            ->orderBy('sorting')
+            ->execute();
+
+        while ($row = $res->fetch()) {
+            $content .= '<li>' . htmlspecialchars($row['title']) . ' [' . htmlspecialchars($row['uid']) . ']</li>';
+        }
+        return '<ul>' . $content . '</ul>';
+    }
+}

typo3/sysext/beuser/Classes/ViewHelpers/IssueCommandViewHelper.php

@@ -0,0 +1,62 @@
+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+use TYPO3Fluid\Fluid\Core\ViewHelper\Traits\CompileWithRenderStatic;
+
+/**
+ * Render a link to DataHandler command
+ * @internal
+ */
+class IssueCommandViewHelper extends AbstractViewHelper
+{
+    use CompileWithRenderStatic;
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        $this->registerArgument('parameters', 'string', 'Is a set of GET params to send to route tce_db (SimpleDataHandlerController). Example: "&cmd[tt_content][123][move]=456" or "&data[tt_content][123][hidden]=1&data[tt_content][123][title]=Hello%20World', true);
+        $this->registerArgument('redirectUrl', 'string', 'Redirect URL if any other that \TYPO3\CMS\Core\Utility\GeneralUtility::getIndpEnv(\'REQUEST_URI\') is preferred', false, '');
+    }
+
+    /**
+     * Returns a URL with a command to TYPO3 Core Engine - DataHandler (route tce_db)
+     *
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     *
+     * @return string URL to tce_db + parameters
+     * @see \TYPO3\CMS\Backend\Utility\BackendUtility::getLinkToDataHandlerAction()
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $urlParameters = [
+            'redirect' => $arguments['redirectUrl'] ?: GeneralUtility::getIndpEnv('REQUEST_URI')
+        ];
+        if (isset($arguments['parameters'])) {
+            $parametersArray = GeneralUtility::explodeUrl2Array($arguments['parameters']);
+            $urlParameters += $parametersArray;
+        }
+        /** @var \TYPO3\CMS\Backend\Routing\UriBuilder $uriBuilder */
+        $uriBuilder = GeneralUtility::makeInstance(\TYPO3\CMS\Backend\Routing\UriBuilder::class);
+        return (string)$uriBuilder->buildUriFromRoute('tce_db', $urlParameters);
+    }
+}

typo3/sysext/beuser/Classes/ViewHelpers/PermissionsViewHelper.php

@@ -0,0 +1,101 @@
+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Extbase\Utility\LocalizationUtility;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+use TYPO3Fluid\Fluid\Core\ViewHelper\Traits\CompileWithRenderStatic;
+
+/**
+ * Render permission icon group (user / group / others) of the "Access" module.
+ *
+ * Most of that could be done in fluid directly, but this ViewHelper
+ * is much better performance wise.
+ * @internal
+ */
+class PermissionsViewHelper extends AbstractViewHelper
+{
+    use CompileWithRenderStatic;
+
+    /**
+     * As this ViewHelper renders HTML, the output must not be escaped.
+     *
+     * @var bool
+     */
+    protected $escapeOutput = false;
+
+    /**
+     * @var array Cached labels for a single permission mask like "Delete page"
+     */
+    protected static $permissionLabels = [];
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        $this->registerArgument('permission', 'int', 'Current permission', true);
+        $this->registerArgument('scope', 'string', '"user" / "group" / "everybody"', true);
+        $this->registerArgument('pageId', 'int', '', true);
+    }
+
+    /**
+     * Return permissions.
+     *
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     * @return string
+     * @throws \TYPO3Fluid\Fluid\Core\ViewHelper\Exception
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $masks = [1, 16, 2, 4, 8];
+
+        if (empty(static::$permissionLabels)) {
+            foreach ($masks as $mask) {
+                static::$permissionLabels[$mask] = LocalizationUtility::translate(
+                    'LLL:EXT:beuser/Resources/Private/Language/locallang_mod_permission.xlf:' . $mask,
+                    'be_user'
+                );
+            }
+        }
+
+        $icon = '';
+        foreach ($masks as $mask) {
+            if ($arguments['permission'] & $mask) {
+                $permissionClass = 'fa-check text-success';
+                $mode = 'delete';
+            } else {
+                $permissionClass = 'fa-times text-danger';
+                $mode = 'add';
+            }
+
+            $label = static::$permissionLabels[$mask];
+            $icon .= '<span style="cursor:pointer"'
+                . ' title="' . htmlspecialchars($label) . '"'
+                . ' data-toggle="tooltip"'
+                . ' data-page="' . htmlspecialchars($arguments['pageId']) . '"'
+                . ' data-permissions="' . htmlspecialchars($arguments['permission']) . '"'
+                . ' data-who="' . htmlspecialchars($arguments['scope']) . '"'
+                . ' data-bits="' . htmlspecialchars($mask) . '"'
+                . ' data-mode="' . htmlspecialchars($mode) . '"'
+                . ' class="t3-icon change-permission fa ' . htmlspecialchars($permissionClass) . '"></span>';
+        }
+
+        return '<span id="' . htmlspecialchars($arguments['pageId'] . '_' . $arguments['scope']) . '">' . $icon . '</span>';
+    }
+}

typo3/sysext/beuser/Classes/ViewHelpers/RemoveUserViewHelper.php

@@ -0,0 +1,59 @@
+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Backend\Routing\UriBuilder;
+use TYPO3\CMS\Beuser\Domain\Model\BackendUser;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+use TYPO3Fluid\Fluid\Core\ViewHelper\Traits\CompileWithRenderStatic;
+
+/**
+ * Renders 'Delete user' link
+ *
+ * @internal
+ */
+class RemoveUserViewHelper extends AbstractViewHelper
+{
+    use CompileWithRenderStatic;
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        $this->registerArgument('backendUser', BackendUser::class, 'Target backendUser to switch active session to', true);
+    }
+
+    /**
+     * Renders the URL to remove a user.
+     *
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     *
+     * @return string
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $urlParameters = [
+            'cmd[be_users][' . $arguments['backendUser']->getUid() . '][delete]' => 1,
+            'redirect' => GeneralUtility::getIndpEnv('REQUEST_URI')
+        ];
+        $uriBuilder = GeneralUtility::makeInstance(UriBuilder::class);
+        return (string)$uriBuilder->buildUriFromRoute('tce_db', $urlParameters);
+    }
+}

typo3/sysext/beuser/Classes/ViewHelpers/SpriteIconForRecordViewHelper.php

@@ -0,0 +1,98 @@
+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Imaging\Icon;
+use TYPO3\CMS\Core\Imaging\IconFactory;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Extbase\Domain\Model\BackendUser;
+use TYPO3\CMS\Fluid\ViewHelpers\Be\AbstractBackendViewHelper;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+
+/**
+ * Views sprite icon for a record (object)
+ * @internal
+ */
+class SpriteIconForRecordViewHelper extends AbstractBackendViewHelper
+{
+    /**
+     * As this ViewHelper renders HTML, the output must not be escaped.
+     *
+     * @var bool
+     */
+    protected $escapeOutput = false;
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        parent::initializeArguments();
+        $this->registerArgument('table', 'string', '', true);
+        $this->registerArgument('object', 'object', '', true);
+    }
+
+    /**
+     * Displays spriteIcon for database table and object
+     *
+     * @return string
+     * @see IconFactory::getIconForRecord()
+     */
+    public function render()
+    {
+        return static::renderStatic($this->arguments, $this->buildRenderChildrenClosure(), $this->renderingContext);
+    }
+
+    /**
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     *
+     * @return string
+     * @throws \Exception
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $object = $arguments['object'];
+        $table = $arguments['table'];
+
+        if (!is_object($object) || !method_exists($object, 'getUid')) {
+            return '';
+        }
+        $row = [
+            'uid' => $object->getUid(),
+            'startTime' => false,
+            'endTime' => false
+        ];
+        if (method_exists($object, 'getIsDisabled')) {
+            $row['disable'] = $object->getIsDisabled();
+        }
+        if (method_exists($object, 'getHidden')) {
+            $row['hidden'] = $object->getHidden();
+        }
+        if ($table === 'be_users' && $object instanceof BackendUser) {
+            $row['admin'] = $object->getIsAdministrator();
+        }
+        if (method_exists($object, 'getStartDateAndTime')) {
+            $row['startTime'] = $object->getStartDateAndTime();
+        }
+        if (method_exists($object, 'getEndDateAndTime')) {
+            $row['endTime'] = $object->getEndDateAndTime();
+        }
+        /** @var IconFactory $iconFactory */
+        $iconFactory = GeneralUtility::makeInstance(IconFactory::class);
+        return $iconFactory->getIconForRecord($table, $row, Icon::SIZE_SMALL)->render();
+    }
+}

typo3/sysext/beuser/Classes/ViewHelpers/SwitchUserViewHelper.php

@@ -0,0 +1,71 @@
+<?php
+namespace TYPO3\CMS\Beuser\ViewHelpers;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Beuser\Domain\Model\BackendUser;
+use TYPO3\CMS\Core\Imaging\Icon;
+use TYPO3\CMS\Core\Imaging\IconFactory;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Extbase\Utility\LocalizationUtility;
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+use TYPO3Fluid\Fluid\Core\ViewHelper\Traits\CompileWithRenderStatic;
+
+/**
+ * Displays 'SwitchUser' link with sprite icon to change current backend user to target (non-admin) backendUser
+ * @internal
+ */
+class SwitchUserViewHelper extends AbstractViewHelper
+{
+    use CompileWithRenderStatic;
+
+    /**
+     * As this ViewHelper renders HTML, the output must not be escaped.
+     *
+     * @var bool
+     */
+    protected $escapeOutput = false;
+
+    /**
+     * Initializes the arguments
+     */
+    public function initializeArguments()
+    {
+        $this->registerArgument('backendUser', BackendUser::class, 'Target backendUser to switch active session to', true);
+    }
+
+    /**
+     * Render link with sprite icon to change current backend user to target
+     *
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     *
+     * @return string
+     */
+    public static function renderStatic(array $arguments, \Closure $renderChildrenClosure, RenderingContextInterface $renderingContext)
+    {
+        $backendUser = $arguments['backendUser'];
+        $iconFactory = GeneralUtility::makeInstance(IconFactory::class);
+        if ($backendUser->getUid() == $GLOBALS['BE_USER']->user['uid'] || !$backendUser->isActive() || $GLOBALS['BE_USER']->user['ses_backuserid']) {
+            return '<span class="btn btn-default disabled">' . $iconFactory->getIcon('empty-empty', Icon::SIZE_SMALL)->render() . '</span>';
+        }
+        $title = LocalizationUtility::translate('switchBackMode', 'beuser');
+        return '<a class="btn btn-default" href="' .
+            htmlspecialchars(GeneralUtility::linkThisScript(['SwitchUser' => $backendUser->getUid()])) .
+            '" target="_top" title="' . htmlspecialchars($title) . '">' .
+            $iconFactory->getIcon('actions-system-backend-user-switch', Icon::SIZE_SMALL)->render() . '</a>';
+    }
+}