Merge branch '7.2RC'7.2

20 files changed, 334 insertions, 43 deletions

diff --git a/vendor/sabre/dav/.github/workflows/ci.yml b/vendor/sabre/dav/.github/workflows/ci.yml
new file mode 100644
index 000000000..f41b38535
--- /dev/null
+++ b/vendor/sabre/dav/.github/workflows/ci.yml
@@ -0,0 +1,127 @@
+name: continuous-integration
+on:
+  push:
+    branches:
+      - master
+      - release/*
+  pull_request:
+
+jobs:
+  code-analysis:
+    runs-on: ubuntu-latest
+    name: Code Analysis (PHP ${{ matrix.php-versions }})
+    strategy:
+      fail-fast: false
+      matrix:
+        php-versions: [ '7.4' ]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Setup PHP, with composer and extensions
+        uses: shivammathur/setup-php@v2 #https://github.com/shivammathur/setup-php
+        with:
+          php-version: ${{ matrix.php-versions }}
+          extensions: mbstring, dom, fileinfo, mysql, redis, opcache
+          tools: composer
+
+      - name: Get composer cache directory
+        id: composer-cache
+        run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+
+      - name: Cache composer dependencies
+        uses: actions/cache@v2
+        with:
+          path: ${{ steps.composer-cache.outputs.dir }}
+          # Use composer.json for key, if composer.lock is not committed.
+          # key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.json') }}
+          key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}
+          restore-keys: ${{ runner.os }}-composer-
+
+      - name: Install Composer dependencies
+        run: composer install --no-progress --prefer-dist --optimize-autoloader
+
+      - name: PHP CS-Fixer
+        run: php vendor/bin/php-cs-fixer fix --dry-run --diff
+
+      - name: PHPStan
+        run: composer phpstan
+
+  unit-testing:
+    name: PHPUnit (PHP ${{ matrix.php-versions }})
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        php-versions: [ '7.1', '7.2', '7.3', '7.4', '8.0' ]
+        coverage: [ 'none' ]
+        streaming: [ false ]
+        include:
+          - php-versions: '8.1'
+            coverage: 'pcov'
+            streaming: true
+
+    services:
+      mariadb:
+        image: mariadb
+        env:
+          MARIADB_DATABASE: 'sabredav_test'
+          MARIADB_ROOT_PASSWORD: root
+        ports:
+          - 3306:3306
+      postgres:
+        image: postgres
+        env:
+          POSTGRES_DB: 'sabredav_test'
+          POSTGRES_PASSWORD: postgres
+        ports:
+          - 5432:5432
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Setup PHP, with composer and extensions
+        uses: shivammathur/setup-php@v2 #https://github.com/shivammathur/setup-php
+        with:
+          php-version: ${{ matrix.php-versions }}
+          extensions: mbstring, dom, fileinfo, pdo_sqlite, pgsql, mysql, redis, opcache
+          coverage: ${{ matrix.coverage }}
+          tools: composer
+
+      - name: Get composer cache directory
+        id: composer-cache
+        run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+
+      - name: Cache composer dependencies
+        uses: actions/cache@v2
+        with:
+          path: ${{ steps.composer-cache.outputs.dir }}
+          # Use composer.json for key, if composer.lock is not committed.
+          # key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.json') }}
+          key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}
+          restore-keys: ${{ runner.os }}-composer-
+
+      - name: Install Composer dependencies
+        run: composer install --no-progress --prefer-dist --optimize-autoloader
+
+      - name: PHPUnit
+        if: matrix.streaming == false
+        run: vendor/bin/phpunit --verbose --configuration tests/phpunit.xml --coverage-clover=coverage.xml
+        env:
+          SABRE_MYSQLUSER: root
+          SABRE_MYSQLPASS: root
+          SABRE_MYSQLDSN: "mysql:host=127.0.0.1;port=3306;dbname=sabredav_test"
+          SABRE_PGSQLDSN: "pgsql:host=127.0.0.1;port=5432;dbname=sabredav_test;user=postgres;password=postgres"
+
+      - name: PHPUnit (with streaming)
+        if: matrix.streaming == true
+        run: vendor/bin/phpunit --verbose --configuration tests/phpunit.xml --coverage-clover=coverage.xml
+        env:
+          SABRE_MYSQLUSER: root
+          SABRE_MYSQLPASS: root
+          SABRE_MYSQLDSN: "mysql:host=127.0.0.1;port=3306;dbname=sabredav_test"
+          SABRE_PGSQLDSN: "pgsql:host=127.0.0.1;port=5432;dbname=sabredav_test;user=postgres;password=postgres"
+          RUN_TEST_WITH_STREAMING_PROPFIND: "true"
+
+      - uses: codecov/codecov-action@v2
+        if: matrix.coverage != 'none'
diff --git a/vendor/sabre/dav/composer.json b/vendor/sabre/dav/composer.json
index 7c9596d21..5f0a44d66 100644
--- a/vendor/sabre/dav/composer.json
+++ b/vendor/sabre/dav/composer.json
@@ -29,7 +29,7 @@
         "ext-date" : "*",
         "ext-iconv" : "*",
         "lib-libxml" : ">=2.7.0",
-        "psr/log": "^1.0",
+        "psr/log": "^1.0 || ^2.0 || ^3.0",
         "ext-json": "*"
     },
     "require-dev" : {
diff --git a/vendor/sabre/dav/lib/CalDAV/Backend/PDO.php b/vendor/sabre/dav/lib/CalDAV/Backend/PDO.php
index 0d5df3968..2f48ab982 100644
--- a/vendor/sabre/dav/lib/CalDAV/Backend/PDO.php
+++ b/vendor/sabre/dav/lib/CalDAV/Backend/PDO.php
@@ -948,42 +948,46 @@ SQL;
         }
         list($calendarId, $instanceId) = $calendarId;
 
-        // Current synctoken
-        $stmt = $this->pdo->prepare('SELECT synctoken FROM '.$this->calendarTableName.' WHERE id = ?');
-        $stmt->execute([$calendarId]);
-        $currentToken = $stmt->fetchColumn(0);
-
-        if (is_null($currentToken)) {
-            return null;
-        }
-
         $result = [
-            'syncToken' => $currentToken,
             'added' => [],
             'modified' => [],
             'deleted' => [],
         ];
 
         if ($syncToken) {
-            $query = 'SELECT uri, operation FROM '.$this->calendarChangesTableName.' WHERE synctoken >= ? AND synctoken < ? AND calendarid = ? ORDER BY synctoken';
+            $query = 'SELECT uri, operation, synctoken FROM '.$this->calendarChangesTableName.' WHERE synctoken >= ?  AND calendarid = ? ORDER BY synctoken';
             if ($limit > 0) {
-                $query .= ' LIMIT '.(int) $limit;
+                // Fetch one more raw to detect result truncation
+                $query .= ' LIMIT '.((int) $limit + 1);
             }
 
             // Fetching all changes
             $stmt = $this->pdo->prepare($query);
-            $stmt->execute([$syncToken, $currentToken, $calendarId]);
+            $stmt->execute([$syncToken, $calendarId]);
 
             $changes = [];
 
             // This loop ensures that any duplicates are overwritten, only the
             // last change on a node is relevant.
             while ($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-                $changes[$row['uri']] = $row['operation'];
+                $changes[$row['uri']] = $row;
             }
+            $currentToken = null;
 
+            $result_count = 0;
             foreach ($changes as $uri => $operation) {
-                switch ($operation) {
+                if (!is_null($limit) && $result_count >= $limit) {
+                    $result['result_truncated'] = true;
+                    break;
+                }
+
+                if (null === $currentToken || $currentToken < $operation['synctoken'] + 1) {
+                    // SyncToken in CalDAV perspective is consistently the next number of the last synced change event in this class.
+                    $currentToken = $operation['synctoken'] + 1;
+                }
+
+                ++$result_count;
+                switch ($operation['operation']) {
                     case 1:
                         $result['added'][] = $uri;
                         break;
@@ -995,7 +999,24 @@ SQL;
                         break;
                 }
             }
+
+            if (!is_null($currentToken)) {
+                $result['syncToken'] = $currentToken;
+            } else {
+                // This means returned value is equivalent to syncToken
+                $result['syncToken'] = $syncToken;
+            }
         } else {
+            // Current synctoken
+            $stmt = $this->pdo->prepare('SELECT synctoken FROM '.$this->calendarTableName.' WHERE id = ?');
+            $stmt->execute([$calendarId]);
+            $currentToken = $stmt->fetchColumn(0);
+
+            if (is_null($currentToken)) {
+                return null;
+            }
+            $result['syncToken'] = $currentToken;
+
             // No synctoken supplied, this is the initial sync.
             $query = 'SELECT uri FROM '.$this->calendarObjectTableName.' WHERE calendarid = ?';
             $stmt = $this->pdo->prepare($query);
diff --git a/vendor/sabre/dav/lib/CalDAV/Calendar.php b/vendor/sabre/dav/lib/CalDAV/Calendar.php
index 9f32e702a..6e989314d 100644
--- a/vendor/sabre/dav/lib/CalDAV/Calendar.php
+++ b/vendor/sabre/dav/lib/CalDAV/Calendar.php
@@ -396,7 +396,8 @@ class Calendar implements ICalendar, DAV\IProperties, DAV\Sync\ISyncCollection,
      *   'deleted' => [
      *      'foo.php.bak',
      *      'old.txt'
-     *   ]
+     *   ],
+     *   'result_truncated' : true
      * ];
      *
      * The syncToken property should reflect the *current* syncToken of the
@@ -406,6 +407,9 @@ class Calendar implements ICalendar, DAV\IProperties, DAV\Sync\ISyncCollection,
      * If the syncToken is specified as null, this is an initial sync, and all
      * members should be reported.
      *
+     * If result is truncated due to server limitation or limit by client,
+     * set result_truncated to true, otherwise set to false or do not add the key.
+     *
      * The modified property is an array of nodenames that have changed since
      * the last token.
      *
@@ -422,12 +426,17 @@ class Calendar implements ICalendar, DAV\IProperties, DAV\Sync\ISyncCollection,
      * should be treated as infinite.
      *
      * If the limit (infinite or not) is higher than you're willing to return,
-     * you should throw a Sabre\DAV\Exception\TooMuchMatches() exception.
+     * the result should be truncated to fit the limit.
+     * Note that even when the result is truncated, syncToken must be consistent
+     * with the truncated result, not the result before truncation.
+     * (See RFC6578 Section 3.6 for detail)
      *
      * If the syncToken is expired (due to data cleanup) or unknown, you must
      * return null.
      *
      * The limit is 'suggestive'. You are free to ignore it.
+     * TODO: RFC6578 Setion 3.7 says that the server must fail when the server
+     * cannot truncate according to the limit, so it may not be just suggestive.
      *
      * @param string $syncToken
      * @param int    $syncLevel
diff --git a/vendor/sabre/dav/lib/CalDAV/Plugin.php b/vendor/sabre/dav/lib/CalDAV/Plugin.php
index da172049e..98f4f554c 100644
--- a/vendor/sabre/dav/lib/CalDAV/Plugin.php
+++ b/vendor/sabre/dav/lib/CalDAV/Plugin.php
@@ -243,7 +243,7 @@ class Plugin extends DAV\ServerPlugin
      * @param mixed  $report
      * @param mixed  $path
      *
-     * @return bool
+     * @return bool|null
      */
     public function report($reportName, $report, $path)
     {
diff --git a/vendor/sabre/dav/lib/CalDAV/Schedule/Plugin.php b/vendor/sabre/dav/lib/CalDAV/Schedule/Plugin.php
index 38a7ca96f..3cc360f1d 100644
--- a/vendor/sabre/dav/lib/CalDAV/Schedule/Plugin.php
+++ b/vendor/sabre/dav/lib/CalDAV/Schedule/Plugin.php
@@ -735,9 +735,7 @@ class Plugin extends ServerPlugin
 
     /**
      * This method is responsible for parsing a free-busy query request and
-     * returning it's result.
-     *
-     * @return string
+     * returning its result in $response.
      */
     protected function handleFreeBusyRequest(IOutbox $outbox, VObject\Component $vObject, RequestInterface $request, ResponseInterface $response)
     {
diff --git a/vendor/sabre/dav/lib/CalDAV/Subscriptions/Subscription.php b/vendor/sabre/dav/lib/CalDAV/Subscriptions/Subscription.php
index 3be1b609e..8d56e6441 100644
--- a/vendor/sabre/dav/lib/CalDAV/Subscriptions/Subscription.php
+++ b/vendor/sabre/dav/lib/CalDAV/Subscriptions/Subscription.php
@@ -75,7 +75,7 @@ class Subscription extends Collection implements ISubscription, IACL
     /**
      * Returns the last modification time.
      *
-     * @return int
+     * @return int|null
      */
     public function getLastModified()
     {
diff --git a/vendor/sabre/dav/lib/DAV/Auth/Backend/PDOBasicAuth.php b/vendor/sabre/dav/lib/DAV/Auth/Backend/PDOBasicAuth.php
new file mode 100644
index 000000000..39324e4db
--- /dev/null
+++ b/vendor/sabre/dav/lib/DAV/Auth/Backend/PDOBasicAuth.php
@@ -0,0 +1,114 @@
+<?php
+
+namespace Sabre\DAV\Auth\Backend;
+
+/**
+ * This is an authentication backend that uses a database to manage passwords.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class PDOBasicAuth extends AbstractBasic
+{
+    /**
+     * Reference to PDO connection.
+     *
+     * @var PDO
+     */
+    protected $pdo;
+
+    /**
+     * PDO table name we'll be using.
+     *
+     * @var string
+     */
+    protected $tableName;
+
+    /**
+     * PDO digest column name we'll be using
+     * (i.e. digest, password, password_hash).
+     *
+     * @var string
+     */
+    protected $digestColumn;
+
+    /**
+     * PDO uuid(unique user identifier) column name we'll be using
+     * (i.e. username, email).
+     *
+     * @var string
+     */
+    protected $uuidColumn;
+
+    /**
+     * Digest prefix:
+     * if the backend you are using for is prefixing
+     * your password hashes set this option to your prefix to
+     * cut it off before verfiying.
+     *
+     * @var string
+     */
+    protected $digestPrefix;
+
+    /**
+     * Creates the backend object.
+     *
+     * If the filename argument is passed in, it will parse out the specified file fist.
+     */
+    public function __construct(\PDO $pdo, array $options = [])
+    {
+        $this->pdo = $pdo;
+        if (isset($options['tableName'])) {
+            $this->tableName = $options['tableName'];
+        } else {
+            $this->tableName = 'users';
+        }
+        if (isset($options['digestColumn'])) {
+            $this->digestColumn = $options['digestColumn'];
+        } else {
+            $this->digestColumn = 'digest';
+        }
+        if (isset($options['uuidColumn'])) {
+            $this->uuidColumn = $options['uuidColumn'];
+        } else {
+            $this->uuidColumn = 'username';
+        }
+        if (isset($options['digestPrefix'])) {
+            $this->digestPrefix = $options['digestPrefix'];
+        }
+    }
+
+    /**
+     * Validates a username and password.
+     *
+     * This method should return true or false depending on if login
+     * succeeded.
+     *
+     * @param string $username
+     * @param string $password
+     *
+     * @return bool
+     */
+    public function validateUserPass($username, $password)
+    {
+        $stmt = $this->pdo->prepare('SELECT '.$this->digestColumn.' FROM '.$this->tableName.' WHERE '.$this->uuidColumn.' = ?');
+        $stmt->execute([$username]);
+        $result = $stmt->fetchAll();
+
+        if (!count($result)) {
+            return false;
+        } else {
+            $digest = $result[0][$this->digestColumn];
+
+            if (isset($this->digestPrefix)) {
+                $digest = substr($digest, strlen($this->digestPrefix));
+            }
+
+            if (password_verify($password, $digest)) {
+                return true;
+            }
+
+            return false;
+        }
+    }
+}
diff --git a/vendor/sabre/dav/lib/DAV/Auth/Plugin.php b/vendor/sabre/dav/lib/DAV/Auth/Plugin.php
index 68adbede5..eb4f27ca6 100644
--- a/vendor/sabre/dav/lib/DAV/Auth/Plugin.php
+++ b/vendor/sabre/dav/lib/DAV/Auth/Plugin.php
@@ -113,8 +113,6 @@ class Plugin extends ServerPlugin
 
     /**
      * This method is called before any HTTP method and forces users to be authenticated.
-     *
-     * @return bool
      */
     public function beforeMethod(RequestInterface $request, ResponseInterface $response)
     {
@@ -204,8 +202,6 @@ class Plugin extends ServerPlugin
      * This method will for example cause a HTTP Basic backend to set a
      * WWW-Authorization header, indicating to the client that it should
      * authenticate.
-     *
-     * @return array
      */
     public function challenge(RequestInterface $request, ResponseInterface $response)
     {
diff --git a/vendor/sabre/dav/lib/DAV/Browser/Plugin.php b/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
index 2f155d9ea..89495e5db 100644
--- a/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
+++ b/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
@@ -85,8 +85,6 @@ class Plugin extends DAV\ServerPlugin
     /**
      * This method intercepts GET requests that have ?sabreAction=info
      * appended to the URL.
-     *
-     * @return bool
      */
     public function httpGetEarly(RequestInterface $request, ResponseInterface $response)
     {
diff --git a/vendor/sabre/dav/lib/DAV/Locks/Plugin.php b/vendor/sabre/dav/lib/DAV/Locks/Plugin.php
index 110bfce06..2443f204c 100644
--- a/vendor/sabre/dav/lib/DAV/Locks/Plugin.php
+++ b/vendor/sabre/dav/lib/DAV/Locks/Plugin.php
@@ -295,6 +295,10 @@ class Plugin extends DAV\ServerPlugin
     {
         $locks = $this->getLocks($path, $includeChildren = true);
         foreach ($locks as $lock) {
+            // don't delete a lock on a parent dir
+            if (0 !== strpos($lock->uri, $path)) {
+                continue;
+            }
             $this->unlockNode($path, $lock);
         }
     }
diff --git a/vendor/sabre/dav/lib/DAV/Server.php b/vendor/sabre/dav/lib/DAV/Server.php
index de663d0c1..1f8300d4a 100644
--- a/vendor/sabre/dav/lib/DAV/Server.php
+++ b/vendor/sabre/dav/lib/DAV/Server.php
@@ -895,7 +895,7 @@ class Server implements LoggerAwareInterface, EmitterInterface
         }
 
         $propertyNames = $propFind->getRequestedProperties();
-        $propFindType = !empty($propertyNames) ? PropFind::NORMAL : PropFind::ALLPROPS;
+        $propFindType = !$propFind->isAllProps() ? PropFind::NORMAL : PropFind::ALLPROPS;
 
         foreach ($this->tree->getChildren($path) as $childNode) {
             if ('' !== $path) {
@@ -1237,6 +1237,7 @@ class Server implements LoggerAwareInterface, EmitterInterface
 
         $this->tree->markDirty($parentUri);
         $this->emit('afterBind', [$uri]);
+        $this->emit('afterCreateCollection', [$uri]);
     }
 
     /**
diff --git a/vendor/sabre/dav/lib/DAV/Sync/Plugin.php b/vendor/sabre/dav/lib/DAV/Sync/Plugin.php
index 32106abb3..8609f759e 100644
--- a/vendor/sabre/dav/lib/DAV/Sync/Plugin.php
+++ b/vendor/sabre/dav/lib/DAV/Sync/Plugin.php
@@ -124,6 +124,10 @@ class Plugin extends DAV\ServerPlugin
             throw new DAV\Exception\InvalidSyncToken('Invalid or unknown sync token');
         }
 
+        if (!array_key_exists('result_truncated', $changeInfo)) {
+            $changeInfo['result_truncated'] = false;
+        }
+
         // Encoding the response
         $this->sendSyncCollectionResponse(
             $changeInfo['syncToken'],
@@ -131,7 +135,8 @@ class Plugin extends DAV\ServerPlugin
             $changeInfo['added'],
             $changeInfo['modified'],
             $changeInfo['deleted'],
-            $report->properties
+            $report->properties,
+            $changeInfo['result_truncated']
         );
     }
 
@@ -141,7 +146,7 @@ class Plugin extends DAV\ServerPlugin
      * @param string $syncToken
      * @param string $collectionUrl
      */
-    protected function sendSyncCollectionResponse($syncToken, $collectionUrl, array $added, array $modified, array $deleted, array $properties)
+    protected function sendSyncCollectionResponse($syncToken, $collectionUrl, array $added, array $modified, array $deleted, array $properties, bool $resultTruncated = false)
     {
         $fullPaths = [];
 
@@ -164,6 +169,10 @@ class Plugin extends DAV\ServerPlugin
             $fullPath = $collectionUrl.'/'.$item;
             $responses[] = new DAV\Xml\Element\Response($fullPath, [], 404);
         }
+        if ($resultTruncated) {
+            $responses[] = new DAV\Xml\Element\Response($collectionUrl.'/', [], 507);
+        }
+
         $multiStatus = new DAV\Xml\Response\MultiStatus($responses, self::SYNCTOKEN_PREFIX.$syncToken);
 
         $this->server->httpResponse->setStatus(207);
diff --git a/vendor/sabre/dav/lib/DAV/Tree.php b/vendor/sabre/dav/lib/DAV/Tree.php
index 2417979a6..8215e2c39 100644
--- a/vendor/sabre/dav/lib/DAV/Tree.php
+++ b/vendor/sabre/dav/lib/DAV/Tree.php
@@ -226,7 +226,7 @@ class Tree
         // flushing the entire cache
         $path = trim($path, '/');
         foreach ($this->cache as $nodePath => $node) {
-            if ('' === $path || $nodePath == $path || 0 === strpos($nodePath, $path.'/')) {
+            if ('' === $path || $nodePath == $path || 0 === strpos((string) $nodePath, $path.'/')) {
                 unset($this->cache[$nodePath]);
             }
         }
diff --git a/vendor/sabre/dav/lib/DAV/Version.php b/vendor/sabre/dav/lib/DAV/Version.php
index b25d6c07a..f8b56bb98 100644
--- a/vendor/sabre/dav/lib/DAV/Version.php
+++ b/vendor/sabre/dav/lib/DAV/Version.php
@@ -16,5 +16,5 @@ class Version
     /**
      * Full version number.
      */
-    public const VERSION = '4.1.5';
+    public const VERSION = '4.3.1';
 }
diff --git a/vendor/sabre/dav/lib/DAV/Xml/Element/Response.php b/vendor/sabre/dav/lib/DAV/Xml/Element/Response.php
index 45c161fa4..79f06a09b 100644
--- a/vendor/sabre/dav/lib/DAV/Xml/Element/Response.php
+++ b/vendor/sabre/dav/lib/DAV/Xml/Element/Response.php
@@ -121,7 +121,7 @@ class Response implements Element
 
         foreach ($this->getResponseProperties() as $status => $properties) {
             // Skipping empty lists
-            if (!$properties || (!ctype_digit($status) && !is_int($status))) {
+            if (!$properties || (!is_int($status) && !ctype_digit($status))) {
                 continue;
             }
             $empty = false;
@@ -186,8 +186,21 @@ class Response implements Element
 
                 return [];
             }
+
+            if (!$reader->read()) {
+                $reader->next();
+
+                return [];
+            }
+
+            if (Reader::END_ELEMENT === $reader->nodeType) {
+                $reader->next();
+
+                return [];
+            }
+
             $values = [];
-            $reader->read();
+
             do {
                 if (Reader::ELEMENT === $reader->nodeType) {
                     $clark = $reader->getClark();
@@ -199,9 +212,12 @@ class Response implements Element
                         $values[$clark] = $reader->parseCurrentElement()['value'];
                     }
                 } else {
-                    $reader->read();
+                    if (!$reader->read()) {
+                        break;
+                    }
                 }
             } while (Reader::END_ELEMENT !== $reader->nodeType);
+
             $reader->read();
 
             return $values;
diff --git a/vendor/sabre/dav/lib/DAVACL/Plugin.php b/vendor/sabre/dav/lib/DAVACL/Plugin.php
index 6f071927d..46d680e15 100644
--- a/vendor/sabre/dav/lib/DAVACL/Plugin.php
+++ b/vendor/sabre/dav/lib/DAVACL/Plugin.php
@@ -927,8 +927,6 @@ class Plugin extends DAV\ServerPlugin
      * Triggered before properties are looked up in specific nodes.
      *
      * @TODO really should be broken into multiple methods, or even a class.
-     *
-     * @return bool
      */
     public function propFind(DAV\PropFind $propFind, DAV\INode $node)
     {
@@ -1070,8 +1068,6 @@ class Plugin extends DAV\ServerPlugin
      * @param string $reportName
      * @param mixed  $report
      * @param mixed  $path
-     *
-     * @return bool
      */
     public function report($reportName, $report, $path)
     {
diff --git a/vendor/sabre/dav/lib/DAVACL/PrincipalBackend/AbstractBackend.php b/vendor/sabre/dav/lib/DAVACL/PrincipalBackend/AbstractBackend.php
index 03a9c4bad..f61a0c953 100644
--- a/vendor/sabre/dav/lib/DAVACL/PrincipalBackend/AbstractBackend.php
+++ b/vendor/sabre/dav/lib/DAVACL/PrincipalBackend/AbstractBackend.php
@@ -33,7 +33,7 @@ abstract class AbstractBackend implements BackendInterface
      * @param string $uri
      * @param string $principalPrefix
      *
-     * @return string
+     * @return string|null
      */
     public function findByUri($uri, $principalPrefix)
     {
diff --git a/vendor/sabre/dav/lib/DAVACL/PrincipalBackend/BackendInterface.php b/vendor/sabre/dav/lib/DAVACL/PrincipalBackend/BackendInterface.php
index 72717a59b..7140a9295 100644
--- a/vendor/sabre/dav/lib/DAVACL/PrincipalBackend/BackendInterface.php
+++ b/vendor/sabre/dav/lib/DAVACL/PrincipalBackend/BackendInterface.php
@@ -110,7 +110,7 @@ interface BackendInterface
      * @param string $uri
      * @param string $principalPrefix
      *
-     * @return string
+     * @return string|null
      */
     public function findByUri($uri, $principalPrefix);
 
diff --git a/vendor/sabre/dav/lib/DAVACL/Xml/Property/Principal.php b/vendor/sabre/dav/lib/DAVACL/Xml/Property/Principal.php
index 24aeffad9..52092128f 100644
--- a/vendor/sabre/dav/lib/DAVACL/Xml/Property/Principal.php
+++ b/vendor/sabre/dav/lib/DAVACL/Xml/Property/Principal.php
@@ -142,6 +142,8 @@ class Principal extends DAV\Xml\Property\Href
             case self::ALL:
                 return '<em>all</em>';
         }
+
+        return '<em>unknown</em>';
     }
 
     /**