diff --git a/settings/Controller/AuthSettingsController.php b/settings/Controller/AuthSettingsController.php
index d1ce567afb..7b68fc4c28 100644
--- a/settings/Controller/AuthSettingsController.php
+++ b/settings/Controller/AuthSettingsController.php
@@ -76,11 +76,11 @@ class AuthSettingsController extends Controller {
 	 * @NoAdminRequired
 	 * @NoSubadminRequired
 	 *
-	 * @return JSONResponse
+	 * @return JSONResponse|array
 	 */
 	public function index() {
 		$user = $this->userManager->get($this->uid);
-		if (is_null($user)) {
+		if ($user === null) {
 			return [];
 		}
 		$tokens = $this->tokenProvider->getTokenByUser($user);
@@ -147,6 +147,9 @@ class AuthSettingsController extends Controller {
 		]);
 	}
 
+	/**
+	 * @return JSONResponse
+	 */
 	private function getServiceNotAvailableResponse() {
 		$resp = new JSONResponse();
 		$resp->setStatus(Http::STATUS_SERVICE_UNAVAILABLE);
@@ -172,7 +175,7 @@ class AuthSettingsController extends Controller {
 	 * @NoAdminRequired
 	 * @NoSubadminRequired
 	 *
-	 * @return JSONResponse
+	 * @return array
 	 */
 	public function destroy($id) {
 		$user = $this->userManager->get($this->uid);
@@ -190,9 +193,10 @@ class AuthSettingsController extends Controller {
 	 *
 	 * @param int $id
 	 * @param array $scope
+	 * @return array
 	 */
 	public function update($id, array $scope) {
-		$token = $this->tokenProvider->getTokenById($id);
+		$token = $this->tokenProvider->getTokenById((string)$id);
 		$token->setScope([
 			'filesystem' => $scope['filesystem']
 		]);
diff --git a/settings/Controller/CertificateController.php b/settings/Controller/CertificateController.php
index 1cf9e03eff..c5f7e89f3f 100644
--- a/settings/Controller/CertificateController.php
+++ b/settings/Controller/CertificateController.php
@@ -72,7 +72,7 @@ class CertificateController extends Controller {
 	 *
 	 * @NoAdminRequired
 	 * @NoSubadminRequired
-	 * @return array
+	 * @return DataResponse
 	 */
 	public function addPersonalRootCertificate() {
 		return $this->addCertificate($this->userCertificateManager);
@@ -114,7 +114,7 @@ class CertificateController extends Controller {
 				$headers
 			);
 		} catch (\Exception $e) {
-			return new DataResponse('An error occurred.', Http::STATUS_UNPROCESSABLE_ENTITY, $headers);
+			return new DataResponse(['An error occurred.'], Http::STATUS_UNPROCESSABLE_ENTITY, $headers);
 		}
 	}
 
@@ -129,7 +129,7 @@ class CertificateController extends Controller {
 	public function removePersonalRootCertificate($certificateIdentifier) {
 
 		if ($this->isCertificateImportAllowed() === false) {
-			return new DataResponse('Individual certificate management disabled', Http::STATUS_FORBIDDEN);
+			return new DataResponse(['Individual certificate management disabled'], Http::STATUS_FORBIDDEN);
 		}
 
 		$this->userCertificateManager->removeCertificate($certificateIdentifier);
@@ -156,7 +156,7 @@ class CertificateController extends Controller {
 	/**
 	 * Add a new personal root certificate to the system's trust store
 	 *
-	 * @return array
+	 * @return DataResponse
 	 */
 	public function addSystemRootCertificate() {
 		return $this->addCertificate($this->systemCertificateManager);
@@ -171,7 +171,7 @@ class CertificateController extends Controller {
 	public function removeSystemRootCertificate($certificateIdentifier) {
 
 		if ($this->isCertificateImportAllowed() === false) {
-			return new DataResponse('Individual certificate management disabled', Http::STATUS_FORBIDDEN);
+			return new DataResponse(['Individual certificate management disabled'], Http::STATUS_FORBIDDEN);
 		}
 
 		$this->systemCertificateManager->removeCertificate($certificateIdentifier);
diff --git a/settings/Controller/ChangePasswordController.php b/settings/Controller/ChangePasswordController.php
index cb1a97386a..e0129af50f 100644
--- a/settings/Controller/ChangePasswordController.php
+++ b/settings/Controller/ChangePasswordController.php
@@ -22,14 +22,15 @@
 namespace OC\Settings\Controller;
 
 use OC\HintException;
+use OC\User\Manager as UserManager;
+use OC\Group\Manager as GroupManager;
+use OC\User\Session;
 use OCP\App\IAppManager;
 use OCP\AppFramework\Controller;
 use OCP\AppFramework\Http\JSONResponse;
-use OCP\IGroupManager;
 use OCP\IL10N;
 use OCP\IRequest;
 use OCP\IUser;
-use OCP\IUserManager;
 use OCP\IUserSession;
 
 class ChangePasswordController extends Controller {
@@ -37,16 +38,16 @@ class ChangePasswordController extends Controller {
 	/** @var string */
 	private $userId;
 
-	/** @var IUserManager */
+	/** @var UserManager */
 	private $userManager;
 
 	/** @var IL10N */
 	private $l;
 
-	/** @var IGroupManager */
+	/** @var GroupManager */
 	private $groupManager;
 
-	/** @var IUserSession */
+	/** @var Session */
 	private $userSession;
 
 	/** @var IAppManager */
@@ -58,18 +59,18 @@ class ChangePasswordController extends Controller {
 	 * @param string $appName
 	 * @param IRequest $request
 	 * @param $userId
-	 * @param IUserManager $userManager
+	 * @param UserManager $userManager
 	 * @param IUserSession $userSession
-	 * @param IGroupManager $groupManager
+	 * @param GroupManager $groupManager
 	 * @param IAppManager $appManager
 	 * @param IL10N $l
 	 */
 	public function __construct($appName,
 								IRequest $request,
 								$userId,
-								IUserManager $userManager,
+								UserManager $userManager,
 								IUserSession $userSession,
-								IGroupManager $groupManager,
+								GroupManager $groupManager,
 								IAppManager $appManager,
 								IL10N $l) {
 		parent::__construct($appName, $request);
diff --git a/tests/Core/Controller/ChangePasswordControllerTest.php b/tests/Core/Controller/ChangePasswordControllerTest.php
index c426bae997..ea3abb58e2 100644
--- a/tests/Core/Controller/ChangePasswordControllerTest.php
+++ b/tests/Core/Controller/ChangePasswordControllerTest.php
@@ -50,9 +50,9 @@ class ChangePasswordControllerTest extends \Test\TestCase {
 	public function setUp() {
 		parent::setUp();
 
-		$this->userManager = $this->createMock(IUserManager::class);
+		$this->userManager = $this->createMock(\OC\User\Manager::class);
 		$this->userSession = $this->createMock(Session::class);
-		$this->groupManager = $this->createMock(IGroupManager::class);
+		$this->groupManager = $this->createMock(\OC\Group\Manager::class);
 		$this->appManager = $this->createMock(IAppManager::class);
 		$this->l = $this->createMock(IL10N::class);
 		$this->l->method('t')->will($this->returnArgument(0));