Fix RedundantPropertyInitializationCheck

For #25839

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

lib/private/Cache/File.php

@@ -49,7 +49,7 @@ class File implements ICache {
 	 * @throws \OC\User\NoUserException
 	 */
 	protected function getStorage() {
-		if (isset($this->storage)) {
+		if ($this->storage !== null) {
 			return $this->storage;
 		}
 		if (\OC::$server->getUserSession()->isLoggedIn()) {

lib/private/Files/Storage/DAV.php

@@ -69,7 +69,7 @@ class DAV extends Common {
 	protected $password;
 	/** @var string */
 	protected $user;
-	/** @var string */
+	/** @var string|null */
 	protected $authType;
 	/** @var string */
 	protected $host;
@@ -143,7 +143,7 @@ class DAV extends Common {
 			'userName' => $this->user,
 			'password' => $this->password,
 		];
-		if (isset($this->authType)) {
+		if ($this->authType !== null) {
 			$settings['authType'] = $this->authType;
 		}
 

lib/private/Route/Router.php

@@ -56,7 +56,7 @@ class Router implements IRouter {
 	protected $root = null;
 	/** @var null|UrlGenerator */
 	protected $generator = null;
-	/** @var string[] */
+	/** @var string[]|null */
 	protected $routingFiles;
 	/** @var bool */
 	protected $loaded = false;
@@ -95,7 +95,7 @@ class Router implements IRouter {
 	 * @return string[]
 	 */
 	public function getRoutingFiles() {
-		if (!isset($this->routingFiles)) {
+		if ($this->routingFiles === null) {
 			$this->routingFiles = [];
 			foreach (\OC_APP::getEnabledApps() as $app) {
 				$appPath = \OC_App::getAppPath($app);

lib/private/User/User.php

@@ -61,7 +61,7 @@ class User implements IUser {
 	/** @var string */
 	private $uid;
 
-	/** @var string */
+	/** @var string|null */
 	private $displayName;
 
 	/** @var UserInterface|null */
@@ -128,7 +128,7 @@ class User implements IUser {
 	 * @return string
 	 */
 	public function getDisplayName() {
-		if (!isset($this->displayName)) {
+		if ($this->displayName === null) {
 			$displayName = '';
 			if ($this->backend && $this->backend->implementsActions(Backend::GET_DISPLAYNAME)) {
 				// get display name and strip whitespace from the beginning and end of it