diff --git a/apps/federation/tests/BackgroundJob/GetSharedSecretTest.php b/apps/federation/tests/BackgroundJob/GetSharedSecretTest.php
index 3da2e2e15e46b..7ac68d618a1c1 100644
--- a/apps/federation/tests/BackgroundJob/GetSharedSecretTest.php
+++ b/apps/federation/tests/BackgroundJob/GetSharedSecretTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -77,12 +78,9 @@ protected function setUp(): void {
 
 	/**
 	 * @dataProvider dataTestExecute
-	 *
-	 * @param bool $isTrustedServer
-	 * @param bool $retainBackgroundJob
 	 */
 	public function testExecute(bool $isTrustedServer, bool $retainBackgroundJob): void {
-		/** @var GetSharedSecret |\PHPUnit\Framework\MockObject\MockObject $getSharedSecret */
+		/** @var GetSharedSecret&MockObject $getSharedSecret */
 		$getSharedSecret = $this->getMockBuilder(GetSharedSecret::class)
 			->setConstructorArgs(
 				[
@@ -95,8 +93,10 @@ public function testExecute(bool $isTrustedServer, bool $retainBackgroundJob): v
 					$this->timeFactory,
 					$this->config,
 				]
-			)->setMethods(['parentStart'])->getMock();
-		$this->invokePrivate($getSharedSecret, 'argument', [['url' => 'url', 'token' => 'token']]);
+			)
+			->onlyMethods(['parentStart'])
+			->getMock();
+		self::invokePrivate($getSharedSecret, 'argument', [['url' => 'url', 'token' => 'token']]);
 
 		$this->trustedServers->expects($this->once())->method('isTrustedServer')
 			->with('url')->willReturn($isTrustedServer);
@@ -105,7 +105,7 @@ public function testExecute(bool $isTrustedServer, bool $retainBackgroundJob): v
 		} else {
 			$getSharedSecret->expects($this->never())->method('parentStart');
 		}
-		$this->invokePrivate($getSharedSecret, 'retainJob', [$retainBackgroundJob]);
+		self::invokePrivate($getSharedSecret, 'retainJob', [$retainBackgroundJob]);
 		$this->jobList->expects($this->once())->method('remove');
 
 		$this->timeFactory->method('getTime')->willReturn(42);
@@ -128,7 +128,7 @@ public function testExecute(bool $isTrustedServer, bool $retainBackgroundJob): v
 		$getSharedSecret->start($this->jobList);
 	}
 
-	public function dataTestExecute() {
+	public static function dataTestExecute(): array {
 		return [
 			[true, true],
 			[true, false],
@@ -138,10 +138,8 @@ public function dataTestExecute() {
 
 	/**
 	 * @dataProvider dataTestRun
-	 *
-	 * @param int $statusCode
 	 */
-	public function testRun($statusCode): void {
+	public function testRun(int $statusCode): void {
 		$target = 'targetURL';
 		$source = 'sourceURL';
 		$token = 'token';
@@ -181,18 +179,18 @@ public function testRun($statusCode): void {
 			$this->trustedServers->expects($this->never())->method('addSharedSecret');
 		}
 
-		$this->invokePrivate($this->getSharedSecret, 'run', [$argument]);
+		self::invokePrivate($this->getSharedSecret, 'run', [$argument]);
 		if (
 			$statusCode !== Http::STATUS_OK
 			&& $statusCode !== Http::STATUS_FORBIDDEN
 		) {
-			$this->assertTrue($this->invokePrivate($this->getSharedSecret, 'retainJob'));
+			$this->assertTrue(self::invokePrivate($this->getSharedSecret, 'retainJob'));
 		} else {
-			$this->assertFalse($this->invokePrivate($this->getSharedSecret, 'retainJob'));
+			$this->assertFalse(self::invokePrivate($this->getSharedSecret, 'retainJob'));
 		}
 	}
 
-	public function dataTestRun() {
+	public static function dataTestRun(): array {
 		return [
 			[Http::STATUS_OK],
 			[Http::STATUS_FORBIDDEN],
@@ -227,7 +225,7 @@ public function testRunExpired(): void {
 				TrustedServers::STATUS_FAILURE
 			);
 
-		$this->invokePrivate($this->getSharedSecret, 'run', [$argument]);
+		self::invokePrivate($this->getSharedSecret, 'run', [$argument]);
 	}
 
 	public function testRunConnectionError(): void {
@@ -263,8 +261,8 @@ public function testRunConnectionError(): void {
 
 		$this->trustedServers->expects($this->never())->method('addSharedSecret');
 
-		$this->invokePrivate($this->getSharedSecret, 'run', [$argument]);
+		self::invokePrivate($this->getSharedSecret, 'run', [$argument]);
 
-		$this->assertTrue($this->invokePrivate($this->getSharedSecret, 'retainJob'));
+		$this->assertTrue(self::invokePrivate($this->getSharedSecret, 'retainJob'));
 	}
 }
diff --git a/apps/federation/tests/BackgroundJob/RequestSharedSecretTest.php b/apps/federation/tests/BackgroundJob/RequestSharedSecretTest.php
index 68f8cc070c80f..8bec10c11e1a9 100644
--- a/apps/federation/tests/BackgroundJob/RequestSharedSecretTest.php
+++ b/apps/federation/tests/BackgroundJob/RequestSharedSecretTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -24,50 +25,28 @@
 use Test\TestCase;
 
 class RequestSharedSecretTest extends TestCase {
-	/** @var MockObject|IClientService */
-	private $httpClientService;
-
-	/** @var MockObject|IClient */
-	private $httpClient;
-
-	/** @var MockObject|IJobList */
-	private $jobList;
-
-	/** @var MockObject|IURLGenerator */
-	private $urlGenerator;
-
-	/** @var MockObject|TrustedServers */
-	private $trustedServers;
-
-	/** @var MockObject|IResponse */
-	private $response;
-
-	/** @var MockObject|IDiscoveryService */
-	private $discoveryService;
-
-	/** @var MockObject|LoggerInterface */
-	private $logger;
-
-	/** @var MockObject|ITimeFactory */
-	private $timeFactory;
-
-	/** @var MockObject|IConfig */
-	private $config;
-
-	/** @var RequestSharedSecret */
-	private $requestSharedSecret;
+	private IClientService&MockObject $httpClientService;
+	private IClient&MockObject $httpClient;
+	private IJobList&MockObject $jobList;
+	private IURLGenerator&MockObject $urlGenerator;
+	private TrustedServers&MockObject $trustedServers;
+	private IResponse&MockObject $response;
+	private IDiscoveryService&MockObject $discoveryService;
+	private LoggerInterface&MockObject $logger;
+	private ITimeFactory&MockObject $timeFactory;
+	private IConfig&MockObject $config;
+	private RequestSharedSecret $requestSharedSecret;
 
 	protected function setUp(): void {
 		parent::setUp();
 
 		$this->httpClientService = $this->createMock(IClientService::class);
-		$this->httpClient = $this->getMockBuilder(IClient::class)->getMock();
-		$this->jobList = $this->getMockBuilder(IJobList::class)->getMock();
-		$this->urlGenerator = $this->getMockBuilder(IURLGenerator::class)->getMock();
-		$this->trustedServers = $this->getMockBuilder(TrustedServers::class)
-			->disableOriginalConstructor()->getMock();
-		$this->response = $this->getMockBuilder(IResponse::class)->getMock();
-		$this->discoveryService = $this->getMockBuilder(IDiscoveryService::class)->getMock();
+		$this->httpClient = $this->createMock(IClient::class);
+		$this->jobList = $this->createMock(IJobList::class);
+		$this->urlGenerator = $this->createMock(IURLGenerator::class);
+		$this->trustedServers = $this->createMock(TrustedServers::class);
+		$this->response = $this->createMock(IResponse::class);
+		$this->discoveryService = $this->createMock(IDiscoveryService::class);
 		$this->logger = $this->createMock(LoggerInterface::class);
 		$this->timeFactory = $this->createMock(ITimeFactory::class);
 		$this->config = $this->createMock(IConfig::class);
@@ -89,13 +68,10 @@ protected function setUp(): void {
 
 	/**
 	 * @dataProvider dataTestStart
-	 *
-	 * @param bool $isTrustedServer
-	 * @param bool $retainBackgroundJob
 	 */
-	public function testStart($isTrustedServer, $retainBackgroundJob): void {
-		/** @var RequestSharedSecret |MockObject $requestSharedSecret */
-		$requestSharedSecret = $this->getMockBuilder('OCA\Federation\BackgroundJob\RequestSharedSecret')
+	public function testStart(bool $isTrustedServer, bool $retainBackgroundJob): void {
+		/** @var RequestSharedSecret&MockObject $requestSharedSecret */
+		$requestSharedSecret = $this->getMockBuilder(RequestSharedSecret::class)
 			->setConstructorArgs(
 				[
 					$this->httpClientService,
@@ -107,8 +83,10 @@ public function testStart($isTrustedServer, $retainBackgroundJob): void {
 					$this->timeFactory,
 					$this->config,
 				]
-			)->setMethods(['parentStart'])->getMock();
-		$this->invokePrivate($requestSharedSecret, 'argument', [['url' => 'url', 'token' => 'token']]);
+			)
+			->onlyMethods(['parentStart'])
+			->getMock();
+		self::invokePrivate($requestSharedSecret, 'argument', [['url' => 'url', 'token' => 'token']]);
 
 		$this->trustedServers->expects($this->once())->method('isTrustedServer')
 			->with('url')->willReturn($isTrustedServer);
@@ -117,7 +95,7 @@ public function testStart($isTrustedServer, $retainBackgroundJob): void {
 		} else {
 			$requestSharedSecret->expects($this->never())->method('parentStart');
 		}
-		$this->invokePrivate($requestSharedSecret, 'retainJob', [$retainBackgroundJob]);
+		self::invokePrivate($requestSharedSecret, 'retainJob', [$retainBackgroundJob]);
 		$this->jobList->expects($this->once())->method('remove');
 
 		$this->timeFactory->method('getTime')->willReturn(42);
@@ -141,7 +119,7 @@ public function testStart($isTrustedServer, $retainBackgroundJob): void {
 		$requestSharedSecret->start($this->jobList);
 	}
 
-	public function dataTestStart() {
+	public static function dataTestStart(): array {
 		return [
 			[true, true],
 			[true, false],
@@ -151,8 +129,6 @@ public function dataTestStart() {
 
 	/**
 	 * @dataProvider dataTestRun
-	 *
-	 * @param int $statusCode
 	 */
 	public function testRun(int $statusCode, int $attempt = 0): void {
 		$target = 'targetURL';
@@ -184,18 +160,18 @@ public function testRun(int $statusCode, int $attempt = 0): void {
 		$this->response->expects($this->once())->method('getStatusCode')
 			->willReturn($statusCode);
 
-		$this->invokePrivate($this->requestSharedSecret, 'run', [$argument]);
+		self::invokePrivate($this->requestSharedSecret, 'run', [$argument]);
 		if (
 			$statusCode !== Http::STATUS_OK
 			&& ($statusCode !== Http::STATUS_FORBIDDEN || $attempt < 5)
 		) {
-			$this->assertTrue($this->invokePrivate($this->requestSharedSecret, 'retainJob'));
+			$this->assertTrue(self::invokePrivate($this->requestSharedSecret, 'retainJob'));
 		} else {
-			$this->assertFalse($this->invokePrivate($this->requestSharedSecret, 'retainJob'));
+			$this->assertFalse(self::invokePrivate($this->requestSharedSecret, 'retainJob'));
 		}
 	}
 
-	public function dataTestRun() {
+	public static function dataTestRun(): array {
 		return [
 			[Http::STATUS_OK],
 			[Http::STATUS_FORBIDDEN, 5],
@@ -231,7 +207,7 @@ public function testRunExpired(): void {
 				TrustedServers::STATUS_FAILURE
 			);
 
-		$this->invokePrivate($this->requestSharedSecret, 'run', [$argument]);
+		self::invokePrivate($this->requestSharedSecret, 'run', [$argument]);
 	}
 
 	public function testRunConnectionError(): void {
@@ -267,7 +243,7 @@ public function testRunConnectionError(): void {
 				]
 			)->willThrowException($this->createMock(ConnectException::class));
 
-		$this->invokePrivate($this->requestSharedSecret, 'run', [$argument]);
-		$this->assertTrue($this->invokePrivate($this->requestSharedSecret, 'retainJob'));
+		self::invokePrivate($this->requestSharedSecret, 'run', [$argument]);
+		$this->assertTrue(self::invokePrivate($this->requestSharedSecret, 'retainJob'));
 	}
 }
diff --git a/apps/federation/tests/Controller/OCSAuthAPIControllerTest.php b/apps/federation/tests/Controller/OCSAuthAPIControllerTest.php
index 9f2d41a10724c..25b0db94e21c2 100644
--- a/apps/federation/tests/Controller/OCSAuthAPIControllerTest.php
+++ b/apps/federation/tests/Controller/OCSAuthAPIControllerTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -8,6 +9,7 @@
 namespace OCA\Federation\Tests\Controller;
 
 use OC\BackgroundJob\JobList;
+use OCA\Federation\BackgroundJob\GetSharedSecret;
 use OCA\Federation\Controller\OCSAuthAPIController;
 use OCA\Federation\DbHandler;
 use OCA\Federation\TrustedServers;
@@ -16,34 +18,19 @@
 use OCP\IRequest;
 use OCP\Security\Bruteforce\IThrottler;
 use OCP\Security\ISecureRandom;
+use PHPUnit\Framework\MockObject\MockObject;
 use Psr\Log\LoggerInterface;
 use Test\TestCase;
 
 class OCSAuthAPIControllerTest extends TestCase {
-	/** @var \PHPUnit\Framework\MockObject\MockObject|IRequest */
-	private $request;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject|ISecureRandom */
-	private $secureRandom;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject|JobList */
-	private $jobList;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject|TrustedServers */
-	private $trustedServers;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject|DbHandler */
-	private $dbHandler;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject|LoggerInterface */
-	private $logger;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject|ITimeFactory */
-	private $timeFactory;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject|IThrottler */
-	private $throttler;
-
+	private IRequest&MockObject $request;
+	private ISecureRandom&MockObject $secureRandom;
+	private JobList&MockObject $jobList;
+	private TrustedServers&MockObject $trustedServers;
+	private DbHandler&MockObject $dbHandler;
+	private LoggerInterface&MockObject $logger;
+	private ITimeFactory&MockObject $timeFactory;
+	private IThrottler&MockObject $throttler;
 	private OCSAuthAPIController $ocsAuthApi;
 
 	/** @var int simulated timestamp */
@@ -91,7 +78,7 @@ public function testRequestSharedSecret(string $token, string $localToken, bool
 
 		if ($ok) {
 			$this->jobList->expects($this->once())->method('add')
-				->with('OCA\Federation\BackgroundJob\GetSharedSecret', ['url' => $url, 'token' => $token, 'created' => $this->currentTime]);
+				->with(GetSharedSecret::class, ['url' => $url, 'token' => $token, 'created' => $this->currentTime]);
 		} else {
 			$this->jobList->expects($this->never())->method('add');
 			$this->jobList->expects($this->never())->method('remove');
@@ -111,7 +98,7 @@ public function testRequestSharedSecret(string $token, string $localToken, bool
 		}
 	}
 
-	public function dataTestRequestSharedSecret() {
+	public static function dataTestRequestSharedSecret(): array {
 		return [
 			['token2', 'token1', true, true],
 			['token1', 'token2', false, false],
@@ -126,8 +113,8 @@ public function testGetSharedSecret(bool $isTrustedServer, bool $isValidToken, b
 		$url = 'url';
 		$token = 'token';
 
-		/** @var OCSAuthAPIController | \PHPUnit\Framework\MockObject\MockObject $ocsAuthApi */
-		$ocsAuthApi = $this->getMockBuilder('OCA\Federation\Controller\OCSAuthAPIController')
+		/** @var OCSAuthAPIController&MockObject $ocsAuthApi */
+		$ocsAuthApi = $this->getMockBuilder(OCSAuthAPIController::class)
 			->setConstructorArgs(
 				[
 					'federation',
@@ -140,7 +127,9 @@ public function testGetSharedSecret(bool $isTrustedServer, bool $isValidToken, b
 					$this->timeFactory,
 					$this->throttler
 				]
-			)->setMethods(['isValidToken'])->getMock();
+			)
+			->onlyMethods(['isValidToken'])
+			->getMock();
 
 		$this->trustedServers
 			->expects($this->any())
@@ -171,7 +160,7 @@ public function testGetSharedSecret(bool $isTrustedServer, bool $isValidToken, b
 		}
 	}
 
-	public function dataTestGetSharedSecret() {
+	public static function dataTestGetSharedSecret(): array {
 		return [
 			[true, true, true],
 			[false, true, false],
diff --git a/apps/federation/tests/Controller/SettingsControllerTest.php b/apps/federation/tests/Controller/SettingsControllerTest.php
index c3e83945e9a8b..d88f397da3420 100644
--- a/apps/federation/tests/Controller/SettingsControllerTest.php
+++ b/apps/federation/tests/Controller/SettingsControllerTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -20,19 +22,18 @@
 class SettingsControllerTest extends TestCase {
 	private SettingsController $controller;
 
-	private MockObject&IRequest $request;
-	private MockObject&IL10N $l10n;
-	private MockObject&TrustedServers $trustedServers;
-	private MockObject&LoggerInterface $logger;
+	private IRequest&MockObject $request;
+	private IL10N&MockObject $l10n;
+	private TrustedServers&MockObject $trustedServers;
+	private LoggerInterface&MockObject $logger;
 
 	protected function setUp(): void {
 		parent::setUp();
 
-		$this->request = $this->getMockBuilder(IRequest::class)->getMock();
-		$this->l10n = $this->getMockBuilder(IL10N::class)->getMock();
-		$this->trustedServers = $this->getMockBuilder(TrustedServers::class)
-			->disableOriginalConstructor()->getMock();
-		$this->logger = $this->getMockBuilder(LoggerInterface::class)->getMock();
+		$this->request = $this->createMock(IRequest::class);
+		$this->l10n = $this->createMock(IL10N::class);
+		$this->trustedServers = $this->createMock(TrustedServers::class);
+		$this->logger = $this->createMock(LoggerInterface::class);
 
 		$this->controller = new SettingsController(
 			'SettingsControllerTest',
@@ -56,7 +57,7 @@ public function testAddServer(): void {
 			->willReturn(true);
 
 		$result = $this->controller->addServer('url');
-		$this->assertTrue($result instanceof DataResponse);
+		$this->assertInstanceOf(DataResponse::class, $result);
 
 		$data = $result->getData();
 		$this->assertSame(200, $result->getStatus());
@@ -110,7 +111,7 @@ public function testCheckServer(): void {
 			->willReturn(true);
 
 		$this->assertNull(
-			$this->invokePrivate($this->controller, 'checkServer', ['url'])
+			self::invokePrivate($this->controller, 'checkServer', ['url'])
 		);
 	}
 
@@ -136,14 +137,11 @@ public function testCheckServerFail(bool $isTrustedServer, bool $isNextcloud): v
 		}
 
 		$this->assertTrue(
-			$this->invokePrivate($this->controller, 'checkServer', ['url'])
+			self::invokePrivate($this->controller, 'checkServer', ['url'])
 		);
 	}
 
-	/**
-	 * Data to simulate checkServer fails
-	 */
-	public function checkServerFails(): array {
+	public static function checkServerFails(): array {
 		return [
 			[true, true],
 			[false, false]
diff --git a/apps/federation/tests/DAV/FedAuthTest.php b/apps/federation/tests/DAV/FedAuthTest.php
index d059fff04812d..c49e6f7e86f47 100644
--- a/apps/federation/tests/DAV/FedAuthTest.php
+++ b/apps/federation/tests/DAV/FedAuthTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -9,27 +10,24 @@
 
 use OCA\Federation\DAV\FedAuth;
 use OCA\Federation\DbHandler;
+use PHPUnit\Framework\MockObject\MockObject;
 use Test\TestCase;
 
 class FedAuthTest extends TestCase {
 
 	/**
 	 * @dataProvider providesUser
-	 *
-	 * @param array $expected
-	 * @param string $user
-	 * @param string $password
 	 */
-	public function testFedAuth($expected, $user, $password): void {
-		/** @var DbHandler | \PHPUnit\Framework\MockObject\MockObject $db */
-		$db = $this->getMockBuilder('OCA\Federation\DbHandler')->disableOriginalConstructor()->getMock();
+	public function testFedAuth(bool $expected, string $user, string $password): void {
+		/** @var DbHandler&MockObject $db */
+		$db = $this->createMock(DbHandler::class);
 		$db->method('auth')->willReturn(true);
 		$auth = new FedAuth($db);
-		$result = $this->invokePrivate($auth, 'validateUserPass', [$user, $password]);
+		$result = self::invokePrivate($auth, 'validateUserPass', [$user, $password]);
 		$this->assertEquals($expected, $result);
 	}
 
-	public function providesUser() {
+	public static function providesUser(): array {
 		return [
 			[true, 'system', '123456']
 		];
diff --git a/apps/federation/tests/DbHandlerTest.php b/apps/federation/tests/DbHandlerTest.php
index 1db9f7f2315bf..a9abdbf776cf2 100644
--- a/apps/federation/tests/DbHandlerTest.php
+++ b/apps/federation/tests/DbHandlerTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -12,30 +13,23 @@
 use OCP\IDBConnection;
 use OCP\IL10N;
 use OCP\Server;
+use PHPUnit\Framework\MockObject\MockObject;
 use Test\TestCase;
 
 /**
  * @group DB
  */
 class DbHandlerTest extends TestCase {
-
-	/** @var DbHandler */
-	private $dbHandler;
-
-	/** @var IL10N | \PHPUnit\Framework\MockObject\MockObject */
-	private $il10n;
-
-	/** @var IDBConnection */
-	private $connection;
-
-	/** @var string */
-	private $dbTable = 'trusted_servers';
+	private DbHandler $dbHandler;
+	private IL10N&MockObject $il10n;
+	private IDBConnection $connection;
+	private string $dbTable = 'trusted_servers';
 
 	protected function setUp(): void {
 		parent::setUp();
 
 		$this->connection = Server::get(IDBConnection::class);
-		$this->il10n = $this->getMockBuilder(IL10N::class)->getMock();
+		$this->il10n = $this->createMock(IL10N::class);
 
 		$this->dbHandler = new DbHandler(
 			$this->connection,
@@ -44,16 +38,17 @@ protected function setUp(): void {
 
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
 
-		$qResult = $query->execute();
+		$qResult = $query->executeQuery();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
 		$this->assertEmpty($result, 'we need to start with a empty trusted_servers table');
 	}
 
 	protected function tearDown(): void {
-		parent::tearDown();
 		$query = $this->connection->getQueryBuilder()->delete($this->dbTable);
-		$query->execute();
+		$query->executeStatement()
+		;
+		parent::tearDown();
 	}
 
 	/**
@@ -63,7 +58,7 @@ protected function tearDown(): void {
 	 * @param string $expectedUrl the url we expect to be written to the db
 	 * @param string $expectedHash the hash value we expect to be written to the db
 	 */
-	public function testAddServer($url, $expectedUrl, $expectedHash): void {
+	public function testAddServer(string $url, string $expectedUrl, string $expectedHash): void {
 		$id = $this->dbHandler->addServer($url);
 
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
@@ -71,14 +66,14 @@ public function testAddServer($url, $expectedUrl, $expectedHash): void {
 		$qResult = $query->execute();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(1, count($result));
+		$this->assertCount(1, $result);
 		$this->assertSame($expectedUrl, $result[0]['url']);
 		$this->assertSame($id, (int)$result[0]['id']);
 		$this->assertSame($expectedHash, $result[0]['url_hash']);
 		$this->assertSame(TrustedServers::STATUS_PENDING, (int)$result[0]['status']);
 	}
 
-	public function dataTestAddServer() {
+	public static function dataTestAddServer(): array {
 		return [
 			['http://owncloud.org', 'http://owncloud.org', sha1('owncloud.org')],
 			['https://owncloud.org', 'https://owncloud.org', sha1('owncloud.org')],
@@ -95,7 +90,7 @@ public function testRemove(): void {
 		$qResult = $query->execute();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(2, count($result));
+		$this->assertCount(2, $result);
 		$this->assertSame('server1', $result[0]['url']);
 		$this->assertSame('server2', $result[1]['url']);
 		$this->assertSame($id1, (int)$result[0]['id']);
@@ -107,7 +102,7 @@ public function testRemove(): void {
 		$qResult = $query->execute();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(1, count($result));
+		$this->assertCount(1, $result);
 		$this->assertSame('server1', $result[0]['url']);
 		$this->assertSame($id1, (int)$result[0]['id']);
 	}
@@ -135,19 +130,15 @@ public function testGetAll(): void {
 
 	/**
 	 * @dataProvider dataTestServerExists
-	 *
-	 * @param string $serverInTable
-	 * @param string $checkForServer
-	 * @param bool $expected
 	 */
-	public function testServerExists($serverInTable, $checkForServer, $expected): void {
+	public function testServerExists(string $serverInTable, string $checkForServer, bool $expected): void {
 		$this->dbHandler->addServer($serverInTable);
 		$this->assertSame($expected,
 			$this->dbHandler->serverExists($checkForServer)
 		);
 	}
 
-	public function dataTestServerExists() {
+	public static function dataTestServerExists(): array {
 		return [
 			['server1', 'server1', true],
 			['server1', 'http://server1', true],
@@ -159,18 +150,18 @@ public function XtestAddToken() {
 		$this->dbHandler->addServer('server1');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
 
-		$qResult = $query->execute();
+		$qResult = $query->executeQuery();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(1, count($result));
+		$this->assertCount(1, $result);
 		$this->assertSame(null, $result[0]['token']);
 		$this->dbHandler->addToken('http://server1', 'token');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
 
-		$qResult = $query->execute();
+		$qResult = $query->executeQuery();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(1, count($result));
+		$this->assertCount(1, $result);
 		$this->assertSame('token', $result[0]['token']);
 	}
 
@@ -189,7 +180,7 @@ public function XtestAddSharedSecret() {
 		$qResult = $query->execute();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(1, count($result));
+		$this->assertCount(1, $result);
 		$this->assertSame(null, $result[0]['shared_secret']);
 		$this->dbHandler->addSharedSecret('http://server1', 'secret');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
@@ -197,7 +188,7 @@ public function XtestAddSharedSecret() {
 		$qResult = $query->execute();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(1, count($result));
+		$this->assertCount(1, $result);
 		$this->assertSame('secret', $result[0]['shared_secret']);
 	}
 
@@ -213,18 +204,18 @@ public function testSetServerStatus(): void {
 		$this->dbHandler->addServer('server1');
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
 
-		$qResult = $query->execute();
+		$qResult = $query->executeQuery();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(1, count($result));
+		$this->assertCount(1, $result);
 		$this->assertSame(TrustedServers::STATUS_PENDING, (int)$result[0]['status']);
 		$this->dbHandler->setServerStatus('http://server1', TrustedServers::STATUS_OK);
 		$query = $this->connection->getQueryBuilder()->select('*')->from($this->dbTable);
 
-		$qResult = $query->execute();
+		$qResult = $query->executeQuery();
 		$result = $qResult->fetchAll();
 		$qResult->closeCursor();
-		$this->assertSame(1, count($result));
+		$this->assertCount(1, $result);
 		$this->assertSame(TrustedServers::STATUS_OK, (int)$result[0]['status']);
 	}
 
@@ -245,17 +236,14 @@ public function testGetServerStatus(): void {
 	 * hash should always be computed with the normalized URL
 	 *
 	 * @dataProvider dataTestHash
-	 *
-	 * @param string $url
-	 * @param string $expected
 	 */
-	public function testHash($url, $expected): void {
+	public function testHash(string $url, string $expected): void {
 		$this->assertSame($expected,
 			$this->invokePrivate($this->dbHandler, 'hash', [$url])
 		);
 	}
 
-	public function dataTestHash() {
+	public static function dataTestHash(): array {
 		return [
 			['server1', sha1('server1')],
 			['http://server1', sha1('server1')],
@@ -266,17 +254,14 @@ public function dataTestHash() {
 
 	/**
 	 * @dataProvider dataTestNormalizeUrl
-	 *
-	 * @param string $url
-	 * @param string $expected
 	 */
-	public function testNormalizeUrl($url, $expected): void {
+	public function testNormalizeUrl(string $url, string $expected): void {
 		$this->assertSame($expected,
 			$this->invokePrivate($this->dbHandler, 'normalizeUrl', [$url])
 		);
 	}
 
-	public function dataTestNormalizeUrl() {
+	public static function dataTestNormalizeUrl(): array {
 		return [
 			['owncloud.org', 'owncloud.org'],
 			['http://owncloud.org', 'owncloud.org'],
@@ -289,7 +274,7 @@ public function dataTestNormalizeUrl() {
 	/**
 	 * @dataProvider providesAuth
 	 */
-	public function testAuth($expectedResult, $user, $password): void {
+	public function testAuth(bool $expectedResult, string $user, string $password): void {
 		if ($expectedResult) {
 			$this->dbHandler->addServer('url1');
 			$this->dbHandler->addSharedSecret('url1', $password);
@@ -298,7 +283,7 @@ public function testAuth($expectedResult, $user, $password): void {
 		$this->assertEquals($expectedResult, $result);
 	}
 
-	public function providesAuth() {
+	public static function providesAuth(): array {
 		return [
 			[false, 'foo', ''],
 			[true, 'system', '123456789'],
diff --git a/apps/federation/tests/Settings/AdminTest.php b/apps/federation/tests/Settings/AdminTest.php
index 3d58fae2d7b30..b4c7121c5c95a 100644
--- a/apps/federation/tests/Settings/AdminTest.php
+++ b/apps/federation/tests/Settings/AdminTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
@@ -9,17 +11,16 @@
 use OCA\Federation\TrustedServers;
 use OCP\AppFramework\Http\TemplateResponse;
 use OCP\IL10N;
+use PHPUnit\Framework\MockObject\MockObject;
 use Test\TestCase;
 
 class AdminTest extends TestCase {
-	/** @var Admin */
-	private $admin;
-	/** @var TrustedServers */
-	private $trustedServers;
+	private TrustedServers&MockObject $trustedServers;
+	private Admin $admin;
 
 	protected function setUp(): void {
 		parent::setUp();
-		$this->trustedServers = $this->getMockBuilder('\OCA\Federation\TrustedServers')->disableOriginalConstructor()->getMock();
+		$this->trustedServers = $this->createMock(\OCA\Federation\TrustedServers::class);
 		$this->admin = new Admin(
 			$this->trustedServers,
 			$this->createMock(IL10N::class)
diff --git a/apps/federation/tests/SyncFederationAddressbooksTest.php b/apps/federation/tests/SyncFederationAddressbooksTest.php
index 39274a11ade1d..aebd4aa2b93f1 100644
--- a/apps/federation/tests/SyncFederationAddressbooksTest.php
+++ b/apps/federation/tests/SyncFederationAddressbooksTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -16,30 +17,21 @@
 use Psr\Log\LoggerInterface;
 
 class SyncFederationAddressbooksTest extends \Test\TestCase {
-
-	/** @var array */
-	private $callBacks = [];
-
-	/** @var MockObject | DiscoveryService */
-	private $discoveryService;
-
-	/** @var MockObject|LoggerInterface */
-	private $logger;
+	private array $callBacks = [];
+	private DiscoveryService&MockObject $discoveryService;
+	private LoggerInterface&MockObject $logger;
 
 	protected function setUp(): void {
 		parent::setUp();
 
-		$this->discoveryService = $this->getMockBuilder(DiscoveryService::class)
-			->disableOriginalConstructor()->getMock();
+		$this->discoveryService = $this->createMock(DiscoveryService::class);
 		$this->discoveryService->expects($this->any())->method('discover')->willReturn([]);
 		$this->logger = $this->createMock(LoggerInterface::class);
 	}
 
 	public function testSync(): void {
-		/** @var DbHandler | MockObject $dbHandler */
-		$dbHandler = $this->getMockBuilder('OCA\Federation\DbHandler')
-			->disableOriginalConstructor()
-			->getMock();
+		/** @var DbHandler&MockObject $dbHandler */
+		$dbHandler = $this->createMock(DbHandler::class);
 		$dbHandler->method('getAllServer')
 			->willReturn([
 				[
@@ -51,9 +43,7 @@ public function testSync(): void {
 			]);
 		$dbHandler->expects($this->once())->method('setServerStatus')->
 			with('https://cloud.drop.box', 1, '1');
-		$syncService = $this->getMockBuilder('OCA\DAV\CardDAV\SyncService')
-			->disableOriginalConstructor()
-			->getMock();
+		$syncService = $this->createMock(SyncService::class);
 		$syncService->expects($this->once())->method('syncRemoteAddressBook')
 			->willReturn('1');
 
@@ -62,14 +52,12 @@ public function testSync(): void {
 		$s->syncThemAll(function ($url, $ex): void {
 			$this->callBacks[] = [$url, $ex];
 		});
-		$this->assertEquals('1', count($this->callBacks));
+		$this->assertCount(1, $this->callBacks);
 	}
 
 	public function testException(): void {
-		/** @var DbHandler | MockObject $dbHandler */
-		$dbHandler = $this->getMockBuilder('OCA\Federation\DbHandler')->
-		disableOriginalConstructor()->
-		getMock();
+		/** @var DbHandler&MockObject $dbHandler */
+		$dbHandler = $this->createMock(DbHandler::class);
 		$dbHandler->method('getAllServer')->
 		willReturn([
 			[
@@ -79,9 +67,7 @@ public function testException(): void {
 				'sync_token' => '0'
 			]
 		]);
-		$syncService = $this->getMockBuilder('OCA\DAV\CardDAV\SyncService')
-			->disableOriginalConstructor()
-			->getMock();
+		$syncService = $this->createMock(SyncService::class);
 		$syncService->expects($this->once())->method('syncRemoteAddressBook')
 			->willThrowException(new \Exception('something did not work out'));
 
@@ -90,14 +76,12 @@ public function testException(): void {
 		$s->syncThemAll(function ($url, $ex): void {
 			$this->callBacks[] = [$url, $ex];
 		});
-		$this->assertEquals(2, count($this->callBacks));
+		$this->assertCount(2, $this->callBacks);
 	}
 
 	public function testSuccessfulSyncWithoutChangesAfterFailure(): void {
-		/** @var DbHandler | MockObject $dbHandler */
-		$dbHandler = $this->getMockBuilder('OCA\Federation\DbHandler')
-			->disableOriginalConstructor()
-			->getMock();
+		/** @var DbHandler&MockObject $dbHandler */
+		$dbHandler = $this->createMock(DbHandler::class);
 		$dbHandler->method('getAllServer')
 			->willReturn([
 				[
@@ -110,9 +94,7 @@ public function testSuccessfulSyncWithoutChangesAfterFailure(): void {
 		$dbHandler->method('getServerStatus')->willReturn(TrustedServers::STATUS_FAILURE);
 		$dbHandler->expects($this->once())->method('setServerStatus')->
 			with('https://cloud.drop.box', 1);
-		$syncService = $this->getMockBuilder('OCA\DAV\CardDAV\SyncService')
-			->disableOriginalConstructor()
-			->getMock();
+		$syncService = $this->createMock(SyncService::class);
 		$syncService->expects($this->once())->method('syncRemoteAddressBook')
 			->willReturn('0');
 
@@ -121,6 +103,6 @@ public function testSuccessfulSyncWithoutChangesAfterFailure(): void {
 		$s->syncThemAll(function ($url, $ex): void {
 			$this->callBacks[] = [$url, $ex];
 		});
-		$this->assertEquals('1', count($this->callBacks));
+		$this->assertCount(1, $this->callBacks);
 	}
 }
diff --git a/apps/federation/tests/TrustedServersTest.php b/apps/federation/tests/TrustedServersTest.php
index c3f0368858bc3..4d64df7a5e19e 100644
--- a/apps/federation/tests/TrustedServersTest.php
+++ b/apps/federation/tests/TrustedServersTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -7,6 +8,7 @@
  */
 namespace OCA\Federation\Tests;
 
+use OCA\Federation\BackgroundJob\RequestSharedSecret;
 use OCA\Federation\DbHandler;
 use OCA\Federation\TrustedServers;
 use OCP\AppFramework\Utility\ITimeFactory;
@@ -19,57 +21,35 @@
 use OCP\Http\Client\IResponse;
 use OCP\IConfig;
 use OCP\Security\ISecureRandom;
+use PHPUnit\Framework\MockObject\MockObject;
 use Psr\Log\LoggerInterface;
 use Test\TestCase;
 
 class TrustedServersTest extends TestCase {
-	/** @var \PHPUnit\Framework\MockObject\MockObject | TrustedServers */
-	private $trustedServers;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | DbHandler */
-	private $dbHandler;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | IClientService */
-	private $httpClientService;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | IClient */
-	private $httpClient;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | IResponse */
-	private $response;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | LoggerInterface */
-	private $logger;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | IJobList */
-	private $jobList;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | ISecureRandom */
-	private $secureRandom;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | IConfig */
-	private $config;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | IEventDispatcher */
-	private $dispatcher;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject|ITimeFactory */
-	private $timeFactory;
+	private TrustedServers $trustedServers;
+	private DbHandler&MockObject $dbHandler;
+	private IClientService&MockObject $httpClientService;
+	private IClient&MockObject $httpClient;
+	private IResponse&MockObject $response;
+	private LoggerInterface&MockObject $logger;
+	private IJobList&MockObject $jobList;
+	private ISecureRandom&MockObject $secureRandom;
+	private IConfig&MockObject $config;
+	private IEventDispatcher&MockObject $dispatcher;
+	private ITimeFactory&MockObject $timeFactory;
 
 	protected function setUp(): void {
 		parent::setUp();
 
-		$this->dbHandler = $this->getMockBuilder(DbHandler::class)
-			->disableOriginalConstructor()->getMock();
-		$this->dispatcher = $this->getMockBuilder(IEventDispatcher::class)
-			->disableOriginalConstructor()->getMock();
-		$this->httpClientService = $this->getMockBuilder(IClientService::class)->getMock();
-		$this->httpClient = $this->getMockBuilder(IClient::class)->getMock();
-		$this->response = $this->getMockBuilder(IResponse::class)->getMock();
-		$this->logger = $this->getMockBuilder(LoggerInterface::class)->getMock();
-		$this->jobList = $this->getMockBuilder(IJobList::class)->getMock();
-		$this->secureRandom = $this->getMockBuilder(ISecureRandom::class)->getMock();
-		$this->config = $this->getMockBuilder(IConfig::class)->getMock();
+		$this->dbHandler = $this->createMock(DbHandler::class);
+		$this->dispatcher = $this->createMock(IEventDispatcher::class);
+		$this->httpClientService = $this->createMock(IClientService::class);
+		$this->httpClient = $this->createMock(IClient::class);
+		$this->response = $this->createMock(IResponse::class);
+		$this->logger = $this->createMock(LoggerInterface::class);
+		$this->jobList = $this->createMock(IJobList::class);
+		$this->secureRandom = $this->createMock(ISecureRandom::class);
+		$this->config = $this->createMock(IConfig::class);
 		$this->timeFactory = $this->createMock(ITimeFactory::class);
 
 		$this->trustedServers = new TrustedServers(
@@ -85,8 +65,8 @@ protected function setUp(): void {
 	}
 
 	public function testAddServer(): void {
-		/** @var \PHPUnit\Framework\MockObject\MockObject|TrustedServers $trustedServers */
-		$trustedServers = $this->getMockBuilder('OCA\Federation\TrustedServers')
+		/** @var TrustedServers&MockObject $trustedServers */
+		$trustedServers = $this->getMockBuilder(TrustedServers::class)
 			->setConstructorArgs(
 				[
 					$this->dbHandler,
@@ -99,7 +79,7 @@ public function testAddServer(): void {
 					$this->timeFactory
 				]
 			)
-			->setMethods(['normalizeUrl', 'updateProtocol'])
+			->onlyMethods(['updateProtocol'])
 			->getMock();
 		$trustedServers->expects($this->once())->method('updateProtocol')
 			->with('url')->willReturn('https://url');
@@ -112,12 +92,12 @@ public function testAddServer(): void {
 			->willReturn('token');
 		$this->dbHandler->expects($this->once())->method('addToken')->with('https://url', 'token');
 		$this->jobList->expects($this->once())->method('add')
-			->with('OCA\Federation\BackgroundJob\RequestSharedSecret',
+			->with(RequestSharedSecret::class,
 				['url' => 'https://url', 'token' => 'token', 'created' => 1234567]);
 
 		$this->assertSame(
-			$trustedServers->addServer('url'),
-			1
+			1,
+			$trustedServers->addServer('url')
 		);
 	}
 
@@ -196,8 +176,8 @@ public function testGetServerStatus(): void {
 	public function testIsNextcloudServer(int $statusCode, bool $isValidNextcloudVersion, bool $expected): void {
 		$server = 'server1';
 
-		/** @var \PHPUnit\Framework\MockObject\MockObject | TrustedServers $trustedServers */
-		$trustedServers = $this->getMockBuilder('OCA\Federation\TrustedServers')
+		/** @var TrustedServers&MockObject $trustedServers */
+		$trustedServers = $this->getMockBuilder(TrustedServers::class)
 			->setConstructorArgs(
 				[
 					$this->dbHandler,
@@ -210,7 +190,7 @@ public function testIsNextcloudServer(int $statusCode, bool $isValidNextcloudVer
 					$this->timeFactory
 				]
 			)
-			->setMethods(['checkNextcloudVersion'])
+			->onlyMethods(['checkNextcloudVersion'])
 			->getMock();
 
 		$this->httpClientService->expects($this->once())->method('newClient')
@@ -236,7 +216,7 @@ public function testIsNextcloudServer(int $statusCode, bool $isValidNextcloudVer
 		);
 	}
 
-	public function dataTestIsNextcloudServer(): array {
+	public static function dataTestIsNextcloudServer(): array {
 		return [
 			[200, true, true],
 			[200, false, false],
@@ -244,19 +224,17 @@ public function dataTestIsNextcloudServer(): array {
 		];
 	}
 
-	/**
-	 * @expectedExceptionMessage simulated exception
-	 */
 	public function testIsNextcloudServerFail(): void {
 		$server = 'server1';
 
-		$this->httpClientService->expects($this->once())->method('newClient')
+		$this->httpClientService->expects($this->once())
+			->method('newClient')
 			->willReturn($this->httpClient);
 
-		$this->httpClient->expects($this->once())->method('get')->with($server . '/status.php')
-			->willReturnCallback(function (): void {
-				throw new \Exception('simulated exception');
-			});
+		$this->httpClient->expects($this->once())
+			->method('get')
+			->with($server . '/status.php')
+			->willThrowException(new \Exception('simulated exception'));
 
 		$this->assertFalse($this->trustedServers->isNextcloudServer($server));
 	}
@@ -264,11 +242,11 @@ public function testIsNextcloudServerFail(): void {
 	/**
 	 * @dataProvider dataTestCheckNextcloudVersion
 	 */
-	public function testCheckNextcloudVersion($status): void {
-		$this->assertTrue($this->invokePrivate($this->trustedServers, 'checkNextcloudVersion', [$status]));
+	public function testCheckNextcloudVersion(string $status): void {
+		$this->assertTrue(self::invokePrivate($this->trustedServers, 'checkNextcloudVersion', [$status]));
 	}
 
-	public function dataTestCheckNextcloudVersion(): array {
+	public static function dataTestCheckNextcloudVersion(): array {
 		return [
 			['{"version":"9.0.0"}'],
 			['{"version":"9.1.0"}']
@@ -282,10 +260,10 @@ public function testCheckNextcloudVersionTooLow(string $status): void {
 		$this->expectException(HintException::class);
 		$this->expectExceptionMessage('Remote server version is too low. 9.0 is required.');
 
-		$this->invokePrivate($this->trustedServers, 'checkNextcloudVersion', [$status]);
+		self::invokePrivate($this->trustedServers, 'checkNextcloudVersion', [$status]);
 	}
 
-	public function dataTestCheckNextcloudVersionTooLow(): array {
+	public static function dataTestCheckNextcloudVersionTooLow(): array {
 		return [
 			['{"version":"8.2.3"}'],
 		];
@@ -296,11 +274,11 @@ public function dataTestCheckNextcloudVersionTooLow(): array {
 	 */
 	public function testUpdateProtocol(string $url, string $expected): void {
 		$this->assertSame($expected,
-			$this->invokePrivate($this->trustedServers, 'updateProtocol', [$url])
+			self::invokePrivate($this->trustedServers, 'updateProtocol', [$url])
 		);
 	}
 
-	public function dataTestUpdateProtocol(): array {
+	public static function dataTestUpdateProtocol(): array {
 		return [
 			['http://owncloud.org', 'http://owncloud.org'],
 			['https://owncloud.org', 'https://owncloud.org'],
diff --git a/apps/files_trashbin/tests/BackgroundJob/ExpireTrashTest.php b/apps/files_trashbin/tests/BackgroundJob/ExpireTrashTest.php
index ee833e6beb8c2..9468fb7add0c0 100644
--- a/apps/files_trashbin/tests/BackgroundJob/ExpireTrashTest.php
+++ b/apps/files_trashbin/tests/BackgroundJob/ExpireTrashTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -18,23 +20,12 @@
 use Test\TestCase;
 
 class ExpireTrashTest extends TestCase {
-	/** @var IAppConfig&MockObject */
-	private $appConfig;
-
-	/** @var IUserManager&MockObject */
-	private $userManager;
-
-	/** @var Expiration&MockObject */
-	private $expiration;
-
-	/** @var IJobList&MockObject */
-	private $jobList;
-
-	/** @var LoggerInterface&MockObject */
-	private $logger;
-
-	/** @var ITimeFactory&MockObject */
-	private $time;
+	private IAppConfig&MockObject $appConfig;
+	private IUserManager&MockObject $userManager;
+	private Expiration&MockObject $expiration;
+	private IJobList&MockObject $jobList;
+	private LoggerInterface&MockObject $logger;
+	private ITimeFactory&MockObject $time;
 
 	protected function setUp(): void {
 		parent::setUp();
diff --git a/apps/files_trashbin/tests/CapabilitiesTest.php b/apps/files_trashbin/tests/CapabilitiesTest.php
index a5e4e79aefd8e..1c460cc566589 100644
--- a/apps/files_trashbin/tests/CapabilitiesTest.php
+++ b/apps/files_trashbin/tests/CapabilitiesTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
@@ -9,9 +11,7 @@
 use Test\TestCase;
 
 class CapabilitiesTest extends TestCase {
-
-	/** @var Capabilities */
-	private $capabilities;
+	private Capabilities $capabilities;
 
 	protected function setUp(): void {
 		parent::setUp();
diff --git a/apps/files_trashbin/tests/Command/CleanUpTest.php b/apps/files_trashbin/tests/Command/CleanUpTest.php
index 25d38752e918a..3dce8f0c92ee0 100644
--- a/apps/files_trashbin/tests/Command/CleanUpTest.php
+++ b/apps/files_trashbin/tests/Command/CleanUpTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -6,12 +8,13 @@
  */
 namespace OCA\Files_Trashbin\Tests\Command;
 
-use OC\User\Manager;
 use OCA\Files_Trashbin\Command\CleanUp;
 use OCP\Files\IRootFolder;
 use OCP\IDBConnection;
+use OCP\IUserManager;
 use OCP\Server;
 use OCP\UserInterface;
+use PHPUnit\Framework\MockObject\MockObject;
 use Symfony\Component\Console\Exception\InvalidOptionException;
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Output\NullOutput;
@@ -26,31 +29,17 @@
  * @package OCA\Files_Trashbin\Tests\Command
  */
 class CleanUpTest extends TestCase {
-
-	/** @var CleanUp */
-	protected $cleanup;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | Manager */
-	protected $userManager;
-
-	/** @var \PHPUnit\Framework\MockObject\MockObject | IRootFolder */
-	protected $rootFolder;
-
-	/** @var IDBConnection */
-	protected $dbConnection;
-
-	/** @var string */
-	protected $trashTable = 'files_trash';
-
-	/** @var string */
-	protected $user0 = 'user0';
+	protected IUserManager&MockObject $userManager;
+	protected IRootFolder&MockObject $rootFolder;
+	protected IDBConnection $dbConnection;
+	protected CleanUp $cleanup;
+	protected string $trashTable = 'files_trash';
+	protected string $user0 = 'user0';
 
 	protected function setUp(): void {
 		parent::setUp();
-		$this->rootFolder = $this->getMockBuilder('OCP\Files\IRootFolder')
-			->disableOriginalConstructor()->getMock();
-		$this->userManager = $this->getMockBuilder('OC\User\Manager')
-			->disableOriginalConstructor()->getMock();
+		$this->rootFolder = $this->createMock(IRootFolder::class);
+		$this->userManager = $this->createMock(IUserManager::class);
 
 		$this->dbConnection = Server::get(IDBConnection::class);
 
@@ -60,9 +49,9 @@ protected function setUp(): void {
 	/**
 	 * populate files_trash table with 10 dummy values
 	 */
-	public function initTable() {
+	public function initTable(): void {
 		$query = $this->dbConnection->getQueryBuilder();
-		$query->delete($this->trashTable)->execute();
+		$query->delete($this->trashTable)->executeStatement();
 		for ($i = 0; $i < 10; $i++) {
 			$query->insert($this->trashTable)
 				->values([
@@ -70,19 +59,18 @@ public function initTable() {
 					'timestamp' => $query->expr()->literal($i),
 					'location' => $query->expr()->literal('.'),
 					'user' => $query->expr()->literal('user' . $i % 2)
-				])->execute();
+				])->executeStatement();
 		}
 		$getAllQuery = $this->dbConnection->getQueryBuilder();
 		$result = $getAllQuery->select('id')
 			->from($this->trashTable)
-			->execute()
+			->executeQuery()
 			->fetchAll();
-		$this->assertSame(10, count($result));
+		$this->assertCount(10, $result);
 	}
 
 	/**
 	 * @dataProvider dataTestRemoveDeletedFiles
-	 * @param boolean $nodeExists
 	 */
 	public function testRemoveDeletedFiles(bool $nodeExists): void {
 		$this->initTable();
@@ -101,7 +89,7 @@ public function testRemoveDeletedFiles(bool $nodeExists): void {
 			$this->rootFolder->expects($this->never())->method('get');
 			$this->rootFolder->expects($this->never())->method('delete');
 		}
-		$this->invokePrivate($this->cleanup, 'removeDeletedFiles', [$this->user0, new NullOutput(), false]);
+		self::invokePrivate($this->cleanup, 'removeDeletedFiles', [$this->user0, new NullOutput(), false]);
 
 		if ($nodeExists) {
 			// if the delete operation was executed only files from user1
@@ -110,11 +98,11 @@ public function testRemoveDeletedFiles(bool $nodeExists): void {
 			$query->select('user')
 				->from($this->trashTable);
 
-			$qResult = $query->execute();
+			$qResult = $query->executeQuery();
 			$result = $qResult->fetchAll();
 			$qResult->closeCursor();
 
-			$this->assertSame(5, count($result));
+			$this->assertCount(5, $result);
 			foreach ($result as $r) {
 				$this->assertSame('user1', $r['user']);
 			}
@@ -124,12 +112,12 @@ public function testRemoveDeletedFiles(bool $nodeExists): void {
 			$getAllQuery = $this->dbConnection->getQueryBuilder();
 			$result = $getAllQuery->select('id')
 				->from($this->trashTable)
-				->execute()
+				->executeQuery()
 				->fetchAll();
-			$this->assertSame(10, count($result));
+			$this->assertCount(10, $result);
 		}
 	}
-	public function dataTestRemoveDeletedFiles() {
+	public static function dataTestRemoveDeletedFiles(): array {
 		return [
 			[true],
 			[false]
@@ -141,8 +129,8 @@ public function dataTestRemoveDeletedFiles() {
 	 */
 	public function testExecuteDeleteListOfUsers(): void {
 		$userIds = ['user1', 'user2', 'user3'];
-		$instance = $this->getMockBuilder('OCA\Files_Trashbin\Command\CleanUp')
-			->setMethods(['removeDeletedFiles'])
+		$instance = $this->getMockBuilder(\OCA\Files_Trashbin\Command\CleanUp::class)
+			->onlyMethods(['removeDeletedFiles'])
 			->setConstructorArgs([$this->rootFolder, $this->userManager, $this->dbConnection])
 			->getMock();
 		$instance->expects($this->exactly(count($userIds)))
@@ -152,8 +140,7 @@ public function testExecuteDeleteListOfUsers(): void {
 			});
 		$this->userManager->expects($this->exactly(count($userIds)))
 			->method('userExists')->willReturn(true);
-		$inputInterface = $this->getMockBuilder('\Symfony\Component\Console\Input\InputInterface')
-			->disableOriginalConstructor()->getMock();
+		$inputInterface = $this->createMock(\Symfony\Component\Console\Input\InputInterface::class);
 		$inputInterface->method('getArgument')
 			->with('user_id')
 			->willReturn($userIds);
@@ -162,9 +149,8 @@ public function testExecuteDeleteListOfUsers(): void {
 				['all-users', false],
 				['verbose', false],
 			]);
-		$outputInterface = $this->getMockBuilder('\Symfony\Component\Console\Output\OutputInterface')
-			->disableOriginalConstructor()->getMock();
-		$this->invokePrivate($instance, 'execute', [$inputInterface, $outputInterface]);
+		$outputInterface = $this->createMock(\Symfony\Component\Console\Output\OutputInterface::class);
+		self::invokePrivate($instance, 'execute', [$inputInterface, $outputInterface]);
 	}
 
 	/**
@@ -173,8 +159,8 @@ public function testExecuteDeleteListOfUsers(): void {
 	public function testExecuteAllUsers(): void {
 		$userIds = [];
 		$backendUsers = ['user1', 'user2'];
-		$instance = $this->getMockBuilder('OCA\Files_Trashbin\Command\CleanUp')
-			->setMethods(['removeDeletedFiles'])
+		$instance = $this->getMockBuilder(\OCA\Files_Trashbin\Command\CleanUp::class)
+			->onlyMethods(['removeDeletedFiles'])
 			->setConstructorArgs([$this->rootFolder, $this->userManager, $this->dbConnection])
 			->getMock();
 		$backend = $this->createMock(UserInterface::class);
@@ -199,7 +185,7 @@ public function testExecuteAllUsers(): void {
 		$this->userManager
 			->method('getBackends')
 			->willReturn([$backend]);
-		$this->invokePrivate($instance, 'execute', [$inputInterface, $outputInterface]);
+		self::invokePrivate($instance, 'execute', [$inputInterface, $outputInterface]);
 	}
 
 	public function testExecuteNoUsersAndNoAllUsers(): void {
@@ -217,7 +203,7 @@ public function testExecuteNoUsersAndNoAllUsers(): void {
 		$this->expectException(InvalidOptionException::class);
 		$this->expectExceptionMessage('Either specify a user_id or --all-users');
 
-		$this->invokePrivate($this->cleanup, 'execute', [$inputInterface, $outputInterface]);
+		self::invokePrivate($this->cleanup, 'execute', [$inputInterface, $outputInterface]);
 	}
 
 	public function testExecuteUsersAndAllUsers(): void {
@@ -235,6 +221,6 @@ public function testExecuteUsersAndAllUsers(): void {
 		$this->expectException(InvalidOptionException::class);
 		$this->expectExceptionMessage('Either specify a user_id or --all-users');
 
-		$this->invokePrivate($this->cleanup, 'execute', [$inputInterface, $outputInterface]);
+		self::invokePrivate($this->cleanup, 'execute', [$inputInterface, $outputInterface]);
 	}
 }
diff --git a/apps/files_trashbin/tests/Command/ExpireTest.php b/apps/files_trashbin/tests/Command/ExpireTest.php
index 4402e07bbb0c9..5a66dac8c6ecf 100644
--- a/apps/files_trashbin/tests/Command/ExpireTest.php
+++ b/apps/files_trashbin/tests/Command/ExpireTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_trashbin/tests/Controller/PreviewControllerTest.php b/apps/files_trashbin/tests/Controller/PreviewControllerTest.php
index 1076870bb9f3c..bb951c9c8c7b1 100644
--- a/apps/files_trashbin/tests/Controller/PreviewControllerTest.php
+++ b/apps/files_trashbin/tests/Controller/PreviewControllerTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
@@ -20,32 +22,18 @@
 use OCP\IRequest;
 use OCP\IUser;
 use OCP\IUserSession;
+use PHPUnit\Framework\MockObject\MockObject;
 use Test\TestCase;
 
 class PreviewControllerTest extends TestCase {
-	/** @var IRootFolder|\PHPUnit\Framework\MockObject\MockObject */
-	private $rootFolder;
-
-	/** @var string */
-	private $userId;
-
-	/** @var IMimeTypeDetector|\PHPUnit\Framework\MockObject\MockObject */
-	private $mimeTypeDetector;
-
-	/** @var IPreview|\PHPUnit\Framework\MockObject\MockObject */
-	private $previewManager;
-
-	/** @var ITimeFactory|\PHPUnit\Framework\MockObject\MockObject */
-	private $time;
-
-	/** @var PreviewController */
-	private $controller;
-
-	/** @var ITrashManager|\PHPUnit\Framework\MockObject\MockObject */
-	private $trashManager;
-
-	/** @var IUserSession|\PHPUnit\Framework\MockObject\MockObject */
-	private $userSession;
+	private IRootFolder&MockObject $rootFolder;
+	private string $userId;
+	private IMimeTypeDetector&MockObject $mimeTypeDetector;
+	private IPreview&MockObject $previewManager;
+	private ITimeFactory&MockObject $time;
+	private ITrashManager&MockObject $trashManager;
+	private IUserSession&MockObject $userSession;
+	private PreviewController $controller;
 
 	protected function setUp(): void {
 		parent::setUp();
diff --git a/apps/files_trashbin/tests/ExpirationTest.php b/apps/files_trashbin/tests/ExpirationTest.php
index 7f026c168067a..aab07de8162a0 100644
--- a/apps/files_trashbin/tests/ExpirationTest.php
+++ b/apps/files_trashbin/tests/ExpirationTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -16,7 +18,7 @@ class ExpirationTest extends \Test\TestCase {
 
 	public const FAKE_TIME_NOW = 1000000;
 
-	public function expirationData() {
+	public static function expirationData(): array {
 		$today = 100 * self::SECONDS_PER_DAY;
 		$back10Days = (100 - 10) * self::SECONDS_PER_DAY;
 		$back20Days = (100 - 20) * self::SECONDS_PER_DAY;
@@ -82,14 +84,8 @@ public function expirationData() {
 
 	/**
 	 * @dataProvider expirationData
-	 *
-	 * @param string $retentionObligation
-	 * @param int $timeNow
-	 * @param int $timestamp
-	 * @param bool $quotaExceeded
-	 * @param string $expectedResult
 	 */
-	public function testExpiration($retentionObligation, $timeNow, $timestamp, $quotaExceeded, $expectedResult): void {
+	public function testExpiration(string $retentionObligation, int $timeNow, int $timestamp, bool $quotaExceeded, bool $expectedResult): void {
 		$mockedConfig = $this->getMockedConfig($retentionObligation);
 		$mockedTimeFactory = $this->getMockedTimeFactory($timeNow);
 
@@ -100,7 +96,7 @@ public function testExpiration($retentionObligation, $timeNow, $timestamp, $quot
 	}
 
 
-	public function timestampTestData(): array {
+	public static function timestampTestData(): array {
 		return [
 			[ 'disabled', false],
 			[ 'auto', false ],
@@ -116,11 +112,8 @@ public function timestampTestData(): array {
 
 	/**
 	 * @dataProvider timestampTestData
-	 *
-	 * @param string $configValue
-	 * @param int $expectedMaxAgeTimestamp
 	 */
-	public function testGetMaxAgeAsTimestamp($configValue, $expectedMaxAgeTimestamp): void {
+	public function testGetMaxAgeAsTimestamp(string $configValue, bool|int $expectedMaxAgeTimestamp): void {
 		$mockedConfig = $this->getMockedConfig($configValue);
 		$mockedTimeFactory = $this->getMockedTimeFactory(
 			self::FAKE_TIME_NOW
@@ -132,10 +125,9 @@ public function testGetMaxAgeAsTimestamp($configValue, $expectedMaxAgeTimestamp)
 	}
 
 	/**
-	 * @param int $time
 	 * @return ITimeFactory|MockObject
 	 */
-	private function getMockedTimeFactory($time) {
+	private function getMockedTimeFactory(int $time) {
 		$mockedTimeFactory = $this->createMock(ITimeFactory::class);
 		$mockedTimeFactory->expects($this->any())
 			->method('getTime')
@@ -145,10 +137,9 @@ private function getMockedTimeFactory($time) {
 	}
 
 	/**
-	 * @param string $returnValue
 	 * @return IConfig|MockObject
 	 */
-	private function getMockedConfig($returnValue) {
+	private function getMockedConfig(string $returnValue) {
 		$mockedConfig = $this->createMock(IConfig::class);
 		$mockedConfig->expects($this->any())
 			->method('getSystemValue')
diff --git a/apps/files_trashbin/tests/Sabre/TrashbinPluginTest.php b/apps/files_trashbin/tests/Sabre/TrashbinPluginTest.php
index 60cc69ba09d83..6c566afc73850 100644
--- a/apps/files_trashbin/tests/Sabre/TrashbinPluginTest.php
+++ b/apps/files_trashbin/tests/Sabre/TrashbinPluginTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
@@ -33,19 +34,23 @@ protected function setUp(): void {
 	 */
 	public function testQuota(int $quota, int $fileSize, bool $expectedResult): void {
 		$fileInfo = $this->createMock(ITrashItem::class);
-		$fileInfo->method('getSize')->willReturn($fileSize);
+		$fileInfo->method('getSize')
+			->willReturn($fileSize);
 
 		$trashNode = $this->createMock(ITrash::class);
-		$trashNode->method('getFileInfo')->willReturn($fileInfo);
+		$trashNode->method('getFileInfo')
+			->willReturn($fileInfo);
 
 		$restoreNode = $this->createMock(RestoreFolder::class);
 
-		$this->server->tree->method('getNodeForPath')->willReturn($trashNode, $restoreNode);
+		$this->server->tree->method('getNodeForPath')
+			->willReturn($trashNode, $restoreNode);
 
 		$previewManager = $this->createMock(IPreview::class);
 
 		$view = $this->createMock(View::class);
-		$view->method('free_space')->willReturn($quota);
+		$view->method('free_space')
+			->willReturn($quota);
 
 		$plugin = new TrashbinPlugin($previewManager, $view);
 		$plugin->initialize($this->server);
@@ -55,7 +60,7 @@ public function testQuota(int $quota, int $fileSize, bool $expectedResult): void
 		$this->assertEquals($expectedResult, $plugin->beforeMove($sourcePath, $destinationPath));
 	}
 
-	public function quotaProvider(): array {
+	public static function quotaProvider(): array {
 		return [
 			[ 1024, 512, true ],
 			[ 512, 513, false ],
diff --git a/apps/files_trashbin/tests/StorageTest.php b/apps/files_trashbin/tests/StorageTest.php
index 5c73e47b307c3..2b2508a358bcb 100644
--- a/apps/files_trashbin/tests/StorageTest.php
+++ b/apps/files_trashbin/tests/StorageTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -27,6 +29,7 @@
 use OCP\Lock\ILockingProvider;
 use OCP\Server;
 use OCP\Share\IShare;
+use PHPUnit\Framework\MockObject\MockObject;
 use Psr\Log\LoggerInterface;
 use Test\Traits\MountProviderTrait;
 
@@ -50,20 +53,9 @@ public function moveFromStorage(IStorage $sourceStorage, string $sourceInternalP
 class StorageTest extends \Test\TestCase {
 	use MountProviderTrait;
 
-	/**
-	 * @var string
-	 */
-	private $user;
-
-	/**
-	 * @var View
-	 */
-	private $rootView;
-
-	/**
-	 * @var View
-	 */
-	private $userView;
+	private string $user;
+	private View $rootView;
+	private View $userView;
 
 	// 239 chars so appended timestamp of 12 chars will exceed max length of 250 chars
 	private const LONG_FILENAME = 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.txt';
@@ -121,7 +113,7 @@ public function testSingleStorageDeleteFile(): void {
 
 		// check if file is in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('test.txt', substr($name, 0, strrpos($name, '.')));
 	}
@@ -138,7 +130,7 @@ public function testSingleStorageDeleteFolder(): void {
 
 		// check if folder is in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('folder', substr($name, 0, strrpos($name, '.')));
 
@@ -162,7 +154,7 @@ public function testSingleStorageDeleteLongFilename(): void {
 
 		// check if file is in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals($truncatedFilename, substr($name, 0, strrpos($name, '.')));
 	}
@@ -181,7 +173,7 @@ public function testSingleStorageDeleteMaxLengthFilename(): void {
 
 		// check if file is in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals($truncatedFilename, substr($name, 0, strrpos($name, '.')));
 	}
@@ -207,7 +199,7 @@ public function testCrossStorageDeleteFile(): void {
 
 		// check if file is in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('subfile.txt', substr($name, 0, strrpos($name, '.')));
 	}
@@ -234,12 +226,12 @@ public function testCrossStorageDeleteFolder(): void {
 
 		// check if folder is in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('folder', substr($name, 0, strrpos($name, '.')));
 
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files/' . $name . '/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('subfile.txt', $name);
 	}
@@ -262,13 +254,13 @@ public function testDeleteVersionsOfFile(): void {
 
 		// check if versions are in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/versions');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('test.txt.v', substr($name, 0, strlen('test.txt.v')));
 
 		// versions deleted
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 	}
 
 	/**
@@ -279,7 +271,7 @@ public function testDeleteVersionsOfFolder(): void {
 		$this->userView->file_put_contents('folder/inside.txt', 'v1');
 
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/folder/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 
 		$this->userView->rmdir('folder');
 
@@ -289,19 +281,19 @@ public function testDeleteVersionsOfFolder(): void {
 
 		// check if versions are in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/versions');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('folder.d', substr($name, 0, strlen('folder.d')));
 
 		// check if versions are in trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/versions/' . $name . '/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('inside.txt.v', substr($name, 0, strlen('inside.txt.v')));
 
 		// versions deleted
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/folder/');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 	}
 
 	/**
@@ -314,12 +306,12 @@ public function testDeleteVersionsOfFileAsRecipient(): void {
 		$this->userView->file_put_contents('share/test.txt', 'v2');
 
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/share/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 
 		$recipientUser = $this->getUniqueId('recipient_');
 		Server::get(IUserManager::class)->createUser($recipientUser, $recipientUser);
 
-		$node = \OC::$server->getUserFolder($this->user)->get('share');
+		$node = \OCP\Server::get(IRootFolder::class)->getUserFolder($this->user)->get('share');
 		$share = Server::get(\OCP\Share\IManager::class)->newShare();
 		$share->setNode($node)
 			->setShareType(IShare::TYPE_USER)
@@ -341,18 +333,18 @@ public function testDeleteVersionsOfFileAsRecipient(): void {
 
 		// check if versions are in trashbin for both users
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/versions');
-		$this->assertEquals(1, count($results), 'Versions in owner\'s trashbin');
+		$this->assertCount(1, $results, 'Versions in owner\'s trashbin');
 		$name = $results[0]->getName();
 		$this->assertEquals('test.txt.v', substr($name, 0, strlen('test.txt.v')));
 
 		$results = $this->rootView->getDirectoryContent($recipientUser . '/files_trashbin/versions');
-		$this->assertEquals(1, count($results), 'Versions in recipient\'s trashbin');
+		$this->assertCount(1, $results, 'Versions in recipient\'s trashbin');
 		$name = $results[0]->getName();
 		$this->assertEquals('test.txt.v', substr($name, 0, strlen('test.txt.v')));
 
 		// versions deleted
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/share/');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 	}
 
 	/**
@@ -366,12 +358,11 @@ public function testDeleteVersionsOfFolderAsRecipient(): void {
 		$this->userView->file_put_contents('share/folder/test.txt', 'v2');
 
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/share/folder/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 
 		$recipientUser = $this->getUniqueId('recipient_');
 		Server::get(IUserManager::class)->createUser($recipientUser, $recipientUser);
-
-		$node = \OC::$server->getUserFolder($this->user)->get('share');
+		$node = \OCP\Server::get(IRootFolder::class)->getUserFolder($this->user)->get('share');
 		$share = Server::get(\OCP\Share\IManager::class)->newShare();
 		$share->setNode($node)
 			->setShareType(IShare::TYPE_USER)
@@ -393,31 +384,31 @@ public function testDeleteVersionsOfFolderAsRecipient(): void {
 
 		// check if versions are in trashbin for owner
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/versions');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('folder.d', substr($name, 0, strlen('folder.d')));
 
 		// check if file versions are in trashbin for owner
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/versions/' . $name . '/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('test.txt.v', substr($name, 0, strlen('test.txt.v')));
 
 		// check if versions are in trashbin for recipient
 		$results = $this->rootView->getDirectoryContent($recipientUser . '/files_trashbin/versions');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('folder.d', substr($name, 0, strlen('folder.d')));
 
 		// check if file versions are in trashbin for recipient
 		$results = $this->rootView->getDirectoryContent($recipientUser . '/files_trashbin/versions/' . $name . '/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 		$name = $results[0]->getName();
 		$this->assertEquals('test.txt.v', substr($name, 0, strlen('test.txt.v')));
 
 		// versions deleted
 		$results = $this->rootView->getDirectoryContent($recipientUser . '/files_versions/share/folder/');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 	}
 
 	/**
@@ -433,10 +424,10 @@ public function testKeepFileAndVersionsWhenMovingFileBetweenStorages(): void {
 		$this->userView->file_put_contents('test.txt', 'v1');
 
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 
 		// move to another storage
 		$this->userView->rename('test.txt', 'substorage/test.txt');
@@ -448,15 +439,15 @@ public function testKeepFileAndVersionsWhenMovingFileBetweenStorages(): void {
 
 		// versions were moved too
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/substorage');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 
 		// check that nothing got trashed by the rename's unlink() call
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 
 		// check that versions were moved and not trashed
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/versions/');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 	}
 
 	/**
@@ -472,10 +463,10 @@ public function testKeepFileAndVersionsWhenMovingFolderBetweenStorages(): void {
 		$this->userView->file_put_contents('folder/inside.txt', 'v1');
 
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/folder/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 
 		// move to another storage
 		$this->userView->rename('folder', 'substorage/folder');
@@ -487,15 +478,15 @@ public function testKeepFileAndVersionsWhenMovingFolderBetweenStorages(): void {
 
 		// versions were moved too
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_versions/substorage/folder/');
-		$this->assertEquals(1, count($results));
+		$this->assertCount(1, $results);
 
 		// check that nothing got trashed by the rename's unlink() call
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 
 		// check that versions were moved and not trashed
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/versions/');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 	}
 
 	/**
@@ -503,11 +494,11 @@ public function testKeepFileAndVersionsWhenMovingFolderBetweenStorages(): void {
 	 */
 	public function testSingleStorageDeleteFileFail(): void {
 		/**
-		 * @var Temporary|\PHPUnit\Framework\MockObject\MockObject $storage
+		 * @var Temporary&MockObject $storage
 		 */
-		$storage = $this->getMockBuilder('\OC\Files\Storage\Temporary')
+		$storage = $this->getMockBuilder(\OC\Files\Storage\Temporary::class)
 			->setConstructorArgs([[]])
-			->setMethods(['rename', 'unlink', 'moveFromStorage'])
+			->onlyMethods(['rename', 'unlink', 'moveFromStorage'])
 			->getMock();
 
 		$storage->expects($this->any())
@@ -532,7 +523,7 @@ public function testSingleStorageDeleteFileFail(): void {
 
 		// file should not be in the trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files/');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 	}
 
 	/**
@@ -540,11 +531,11 @@ public function testSingleStorageDeleteFileFail(): void {
 	 */
 	public function testSingleStorageDeleteFolderFail(): void {
 		/**
-		 * @var Temporary|\PHPUnit\Framework\MockObject\MockObject $storage
+		 * @var Temporary&MockObject $storage
 		 */
-		$storage = $this->getMockBuilder('\OC\Files\Storage\Temporary')
+		$storage = $this->getMockBuilder(\OC\Files\Storage\Temporary::class)
 			->setConstructorArgs([[]])
-			->setMethods(['rename', 'unlink', 'rmdir'])
+			->onlyMethods(['rename', 'unlink', 'rmdir'])
 			->getMock();
 
 		$storage->expects($this->any())
@@ -566,18 +557,17 @@ public function testSingleStorageDeleteFolderFail(): void {
 
 		// file should not be in the trashbin
 		$results = $this->rootView->getDirectoryContent($this->user . '/files_trashbin/files/');
-		$this->assertEquals(0, count($results));
+		$this->assertCount(0, $results);
 	}
 
 	/**
 	 * @dataProvider dataTestShouldMoveToTrash
 	 */
-	public function testShouldMoveToTrash($mountPoint, $path, $userExists, $appDisablesTrash, $expected): void {
+	public function testShouldMoveToTrash(string $mountPoint, string $path, bool $userExists, bool $appDisablesTrash, bool $expected): void {
 		$fileID = 1;
 		$cache = $this->createMock(ICache::class);
 		$cache->expects($this->any())->method('getId')->willReturn($fileID);
-		$tmpStorage = $this->getMockBuilder('\OC\Files\Storage\Temporary')
-			->disableOriginalConstructor()->getMock($cache);
+		$tmpStorage = $this->createMock(\OC\Files\Storage\Temporary::class);
 		$tmpStorage->expects($this->any())->method('getCache')->willReturn($cache);
 		$userManager = $this->getMockBuilder(IUserManager::class)
 			->disableOriginalConstructor()->getMock();
@@ -606,7 +596,9 @@ public function testShouldMoveToTrash($mountPoint, $path, $userExists, $appDisab
 					$eventDispatcher,
 					$rootFolder
 				]
-			)->setMethods(['createMoveToTrashEvent'])->getMock();
+			)
+			->onlyMethods(['createMoveToTrashEvent'])
+			->getMock();
 
 		$storage->expects($this->any())->method('createMoveToTrashEvent')->with($node)
 			->willReturn($event);
@@ -616,7 +608,7 @@ public function testShouldMoveToTrash($mountPoint, $path, $userExists, $appDisab
 		);
 	}
 
-	public function dataTestShouldMoveToTrash() {
+	public static function dataTestShouldMoveToTrash(): array {
 		return [
 			['/schiesbn/', '/files/test.txt', true, false, true],
 			['/schiesbn/', '/files/test.txt', false, false, false],
diff --git a/apps/files_trashbin/tests/TrashbinTest.php b/apps/files_trashbin/tests/TrashbinTest.php
index 3d2ceee0dcd54..d8486ccbdc20e 100644
--- a/apps/files_trashbin/tests/TrashbinTest.php
+++ b/apps/files_trashbin/tests/TrashbinTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare(strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
@@ -22,6 +24,7 @@
 use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\Constants;
 use OCP\Files\FileInfo;
+use OCP\Files\IRootFolder;
 use OCP\IConfig;
 use OCP\IDBConnection;
 use OCP\IUserManager;
@@ -41,16 +44,8 @@ class TrashbinTest extends \Test\TestCase {
 	private $trashRoot2;
 
 	private static $rememberRetentionObligation;
-
-	/**
-	 * @var bool
-	 */
-	private static $trashBinStatus;
-
-	/**
-	 * @var View
-	 */
-	private $rootView;
+	private static bool $trashBinStatus;
+	private View $rootView;
 
 	public static function setUpBeforeClass(): void {
 		parent::setUpBeforeClass();
@@ -74,7 +69,7 @@ public static function setUpBeforeClass(): void {
 
 		$config = Server::get(IConfig::class);
 		//configure trashbin
-		self::$rememberRetentionObligation = $config->getSystemValue('trashbin_retention_obligation', Expiration::DEFAULT_RETENTION_OBLIGATION);
+		self::$rememberRetentionObligation = (string)$config->getSystemValue('trashbin_retention_obligation', Expiration::DEFAULT_RETENTION_OBLIGATION);
 		/** @var Expiration $expiration */
 		$expiration = Server::get(Expiration::class);
 		$expiration->setRetentionObligation('auto, 2');
@@ -190,14 +185,14 @@ public function testExpireOldFiles(): void {
 
 		// only file2.txt should be left
 		$remainingFiles = array_slice($manipulatedList, $count);
-		$this->assertSame(1, count($remainingFiles));
+		$this->assertCount(1, $remainingFiles);
 		$remainingFile = reset($remainingFiles);
 		// TODO: failing test
 		#$this->assertSame('file2.txt', $remainingFile['name']);
 
 		// check that file1.txt and file3.txt was really deleted
 		$newTrashContent = Helper::getTrashFiles('/', self::TEST_TRASHBIN_USER1);
-		$this->assertSame(1, count($newTrashContent));
+		$this->assertCount(1, $newTrashContent);
 		$element = reset($newTrashContent);
 		// TODO: failing test
 		#$this->assertSame('file2.txt', $element['name']);
@@ -285,8 +280,8 @@ public function testExpireOldFilesShared(): void {
 	 * @param FileInfo[] $result
 	 * @param string[] $expected
 	 */
-	private function verifyArray($result, $expected) {
-		$this->assertSame(count($expected), count($result));
+	private function verifyArray(array $result, array $expected): void {
+		$this->assertCount(count($expected), $result);
 		foreach ($expected as $expectedFile) {
 			$found = false;
 			foreach ($result as $fileInTrash) {
@@ -304,10 +299,8 @@ private function verifyArray($result, $expected) {
 
 	/**
 	 * @param FileInfo[] $files
-	 * @param string $trashRoot
-	 * @param integer $expireDate
 	 */
-	private function manipulateDeleteTime($files, $trashRoot, $expireDate) {
+	private function manipulateDeleteTime(array $files, string $trashRoot, int $expireDate): array {
 		$counter = 0;
 		foreach ($files as &$file) {
 			// modify every second file
@@ -361,7 +354,7 @@ public function testExpireOldFilesUtilLimitsAreMet(): void {
 	 * Test restoring a file
 	 */
 	public function testRestoreFileInRoot(): void {
-		$userFolder = \OC::$server->getUserFolder();
+		$userFolder = \OCP\Server::get(IRootFolder::class)->getUserFolder(self::TEST_TRASHBIN_USER1);
 		$file = $userFolder->newFile('file1.txt');
 		$file->putContent('foo');
 
@@ -393,7 +386,7 @@ public function testRestoreFileInRoot(): void {
 	 * Test restoring a file in subfolder
 	 */
 	public function testRestoreFileInSubfolder(): void {
-		$userFolder = \OC::$server->getUserFolder();
+		$userFolder = \OCP\Server::get(IRootFolder::class)->getUserFolder(self::TEST_TRASHBIN_USER1);
 		$folder = $userFolder->newFolder('folder');
 		$file = $folder->newFile('file1.txt');
 		$file->putContent('foo');
@@ -426,7 +419,7 @@ public function testRestoreFileInSubfolder(): void {
 	 * Test restoring a folder
 	 */
 	public function testRestoreFolder(): void {
-		$userFolder = \OC::$server->getUserFolder();
+		$userFolder = \OCP\Server::get(IRootFolder::class)->getUserFolder(self::TEST_TRASHBIN_USER1);
 		$folder = $userFolder->newFolder('folder');
 		$file = $folder->newFile('file1.txt');
 		$file->putContent('foo');
@@ -459,7 +452,7 @@ public function testRestoreFolder(): void {
 	 * Test restoring a file from inside a trashed folder
 	 */
 	public function testRestoreFileFromTrashedSubfolder(): void {
-		$userFolder = \OC::$server->getUserFolder();
+		$userFolder = \OCP\Server::get(IRootFolder::class)->getUserFolder(self::TEST_TRASHBIN_USER1);
 		$folder = $userFolder->newFolder('folder');
 		$file = $folder->newFile('file1.txt');
 		$file->putContent('foo');
@@ -493,7 +486,7 @@ public function testRestoreFileFromTrashedSubfolder(): void {
 	 * The file should then land in the root.
 	 */
 	public function testRestoreFileWithMissingSourceFolder(): void {
-		$userFolder = \OC::$server->getUserFolder();
+		$userFolder = \OCP\Server::get(IRootFolder::class)->getUserFolder(self::TEST_TRASHBIN_USER1);
 		$folder = $userFolder->newFolder('folder');
 		$file = $folder->newFile('file1.txt');
 		$file->putContent('foo');
@@ -530,7 +523,7 @@ public function testRestoreFileWithMissingSourceFolder(): void {
 	 * with the same name in the root folder
 	 */
 	public function testRestoreFileDoesNotOverwriteExistingInRoot(): void {
-		$userFolder = \OC::$server->getUserFolder();
+		$userFolder = \OCP\Server::get(IRootFolder::class)->getUserFolder(self::TEST_TRASHBIN_USER1);
 		$file = $userFolder->newFile('file1.txt');
 		$file->putContent('foo');
 
@@ -570,7 +563,7 @@ public function testRestoreFileDoesNotOverwriteExistingInRoot(): void {
 	 * with the same name in the source folder
 	 */
 	public function testRestoreFileDoesNotOverwriteExistingInSubfolder(): void {
-		$userFolder = \OC::$server->getUserFolder();
+		$userFolder = \OCP\Server::get(IRootFolder::class)->getUserFolder(self::TEST_TRASHBIN_USER1);
 		$folder = $userFolder->newFolder('folder');
 		$file = $folder->newFile('file1.txt');
 		$file->putContent('foo');
@@ -624,7 +617,7 @@ public function testRestoreUnexistingFile(): void {
 	 * the file to root instead
 	 */
 	public function testRestoreFileIntoReadOnlySourceFolder(): void {
-		$userFolder = \OC::$server->getUserFolder();
+		$userFolder = \OCP\Server::get(IRootFolder::class)->getUserFolder(self::TEST_TRASHBIN_USER1);
 		$folder = $userFolder->newFolder('folder');
 		$file = $folder->newFile('file1.txt');
 		$file->putContent('foo');
@@ -680,7 +673,7 @@ public static function loginHelper($user, $create = false) {
 		Filesystem::tearDown();
 		\OC_User::setUserId($user);
 		\OC_Util::setupFS($user);
-		\OC::$server->getUserFolder($user);
+		\OCP\Server::get(IRootFolder::class)->getUserFolder($user);
 	}
 }
 
diff --git a/lib/private/User/Manager.php b/lib/private/User/Manager.php
index c872b43933100..229f3138e6d78 100644
--- a/lib/private/User/Manager.php
+++ b/lib/private/User/Manager.php
@@ -724,7 +724,7 @@ public function validateUserId(string $uid, bool $checkDataDirectory = false): v
 
 		// User ID is too long
 		if (strlen($uid) > IUser::MAX_USERID_LENGTH) {
-		    // TRANSLATORS User ID is too long
+			// TRANSLATORS User ID is too long
 			throw new \InvalidArgumentException($l->t('Username is too long'));
 		}