Some more deprecation fixups

src/Collection/Api/Notifications.php

@@ -29,6 +29,7 @@ class Notifications extends BaseCollection
 	/**
 	 * @return Notification
 	 */
+	#[\ReturnTypeWillChange]
 	public function current()
 	{
 		return parent::current();

src/Util/ACLFormatter.php

@@ -35,7 +35,7 @@ final class ACLFormatter
 	 *
 	 * @return array The array based on the IDs (empty in case there is no list)
 	 */
-	public function expand(string $acl_string = null)
+	public function expand(string $acl_string = null): array
 	{
 		// In case there is no ID list, return empty array (=> no ACL set)
 		if (empty($acl_string)) {
@@ -55,7 +55,7 @@ final class ACLFormatter
 	 * @param string|null $acl_string
 	 * @return string
 	 */
-	public function sanitize(string $acl_string = null)
+	public function sanitize(string $acl_string = null): string
 	{
 		if (empty($acl_string)) {
 			return '';
@@ -107,10 +107,13 @@ final class ACLFormatter
 	 *
 	 * @return string
 	 */
-	function toString($permissions) {
+	function toString($permissions): string
+	{
 		$return = '';
 		if (is_array($permissions)) {
 			$item = $permissions;
+		} elseif (empty($permissions)) {
+			return '';
 		} else {
 			$item = explode(',', $permissions);
 		}

src/Util/ReversedFileReader.php

@@ -89,7 +89,7 @@ class ReversedFileReader implements \Iterator
 	 *
 	 * @return string|null Depending on data being buffered
 	 */
-	private function _readline()
+	private function _readline(): ?string
 	{
 		$buffer = & $this->buffer;
 		while (true) {
@@ -112,6 +112,7 @@ class ReversedFileReader implements \Iterator
 	 * @see Iterator::next()
 	 * @return void
 	 */
+	#[\ReturnTypeWillChange]
 	public function next()
 	{
 		++$this->key;
@@ -124,6 +125,7 @@ class ReversedFileReader implements \Iterator
 	 * @see Iterator::rewind()
 	 * @return void
 	 */
+	#[\ReturnTypeWillChange]
 	public function rewind()
 	{
 		if ($this->filesize > 0) {

tests/Util/Intercept.php

@@ -37,7 +37,7 @@ class Intercept extends php_user_filter
 	public static $cache = '';
 
 	/** @noinspection PhpMissingParentCallCommonInspection */
-	public function filter($in, $out, &$consumed, $closing)
+	public function filter($in, $out, &$consumed, $closing): int
 	{
 		while ($bucket = stream_bucket_make_writeable($in)) {
 			self::$cache .= $bucket->data;

tests/src/Database/DatabaseTest.php

@@ -30,6 +30,15 @@ class DatabaseTest extends FixtureTest
 {
 	use CreateDatabaseTrait;
 
+	/**
+	 * @var Cache
+	 */
+	protected $configCache;
+	/**
+	 * @var ConfigFileManager
+	 */
+	protected $configFileManager;
+
 	protected function setUp(): void
 	{
 		$this->setUpVfsDir();