diff --git a/tests/phpunit/includes/filerepo/file/FileTest.php b/tests/phpunit/includes/filerepo/file/FileTest.php
index 6d8ac700c67..8e0da2ea592 100644
--- a/tests/phpunit/includes/filerepo/file/FileTest.php
+++ b/tests/phpunit/includes/filerepo/file/FileTest.php
@@ -477,7 +477,7 @@ class FileTest extends MediaWikiMediaTestCase {
 	 * @covers File::getHandlerState
 	 */
 	public function testSetHandlerState() {
-		$obj = new stdClass;
+		$obj = (object)[];
 		$file = new class extends File {
 			public function __construct() {
 			}
diff --git a/tests/phpunit/integration/includes/user/UserRightsProxyTest.php b/tests/phpunit/integration/includes/user/UserRightsProxyTest.php
index d3882a97670..b55cd818a75 100644
--- a/tests/phpunit/integration/includes/user/UserRightsProxyTest.php
+++ b/tests/phpunit/integration/includes/user/UserRightsProxyTest.php
@@ -5,7 +5,6 @@ namespace MediaWiki\Tests\User;
 use MediaWiki\User\UserGroupManager;
 use MediaWiki\User\UserGroupManagerFactory;
 use MediaWikiIntegrationTestCase;
-use stdClass;
 use UserRightsProxy;
 use Wikimedia\Rdbms\ILoadBalancer;
 use Wikimedia\Rdbms\LBFactory;
@@ -27,9 +26,10 @@ class UserRightsProxyTest extends MediaWikiIntegrationTestCase {
 
 		$dbMock = $this->createMock( MaintainableDBConnRef::class );
 
-		$row = new stdClass;
-		$row->user_name = 'UserRightsProxyTest';
-		$row->user_id = 12345;
+		$row = (object)[
+			'user_name' => 'UserRightsProxyTest',
+			'user_id' => 12345,
+		];
 		$dbMock->method( 'selectRow' )->willReturn( $row );
 
 		$lbMock = $this->createMock( ILoadBalancer::class );
@@ -138,7 +138,7 @@ class UserRightsProxyTest extends MediaWikiIntegrationTestCase {
 		$userGroupManagerMock
 			->expects( $this->once() )
 			->method( 'getUserGroupMemberships' )
-			->willReturn( [ 'bot' => new stdClass, 'sysop' => new stdClass ] );
+			->willReturn( [ 'bot' => (object)[], 'sysop' => (object)[] ] );
 		$userGroupManagerFactoryMock = $this->createMock( UserGroupManagerFactory::class );
 		$userGroupManagerFactoryMock
 			->method( 'getUserGroupManager' )
@@ -161,7 +161,7 @@ class UserRightsProxyTest extends MediaWikiIntegrationTestCase {
 		$userGroupManagerMock2
 			->expects( $this->exactly( 2 ) )
 			->method( 'getUserGroupMemberships' )
-			->willReturn( [ 'bot' => new stdClass ] );
+			->willReturn( [ 'bot' => (object)[] ] );
 		$userGroupManagerFactoryMock2 = $this->createMock( UserGroupManagerFactory::class );
 		$userGroupManagerFactoryMock2
 			->method( 'getUserGroupManager' )
@@ -184,9 +184,10 @@ class UserRightsProxyTest extends MediaWikiIntegrationTestCase {
 		$value = 'bar';
 
 		$dbMock = $this->createMock( MaintainableDBConnRef::class );
-		$row = new stdClass;
-		$row->user_name = 'UserRightsProxyTest';
-		$row->user_id = 12345;
+		$row = (object)[
+			'user_name' => 'UserRightsProxyTest',
+			'user_id' => 12345,
+		];
 		$dbMock->method( 'selectRow' )->willReturn( $row );
 		$dbMock->method( 'timestamp' )->willReturn( 'timestamp' );
 		$dbMock->method( 'getDomainID' )->willReturn( 'foowiki' );
diff --git a/tests/phpunit/unit/includes/json/JsonCodecTest.php b/tests/phpunit/unit/includes/json/JsonCodecTest.php
index 7d1849d1974..632c7e27ef5 100644
--- a/tests/phpunit/unit/includes/json/JsonCodecTest.php
+++ b/tests/phpunit/unit/includes/json/JsonCodecTest.php
@@ -8,7 +8,6 @@ use JsonSerializable;
 use MediaWiki\Json\JsonCodec;
 use MediaWiki\Json\JsonConstants;
 use MediaWikiUnitTestCase;
-use stdClass;
 use Title;
 use Wikimedia\Assert\PreconditionException;
 
@@ -136,7 +135,7 @@ class JsonCodecTest extends MediaWikiUnitTestCase {
 		yield 'Null' => [ null, true, null ];
 		yield 'Class' => [ $classInstance, false, '$' ];
 		yield 'Empty array' => [ [], true, null ];
-		yield 'Empty stdClass' => [ new stdClass(), true, null ];
+		yield 'Empty stdClass' => [ (object)[], true, null ];
 		yield 'Non-empty array' => [ [ 1, 2, 3 ], true, null ];
 		yield 'Non-empty map' => [ [ 'a' => 'b' ], true, null ];
 		yield 'Nested, serializable' => [ [ 'a' => [ 'b' => [ 'c' => 'd' ] ] ], true, null ];
diff --git a/tests/phpunit/unit/includes/media/TrivialMediaHandlerStateTest.php b/tests/phpunit/unit/includes/media/TrivialMediaHandlerStateTest.php
index 17e46d049f6..7acafbee0c5 100644
--- a/tests/phpunit/unit/includes/media/TrivialMediaHandlerStateTest.php
+++ b/tests/phpunit/unit/includes/media/TrivialMediaHandlerStateTest.php
@@ -5,7 +5,7 @@
  */
 class TrivialMediaHandlerStateTest extends MediaWikiUnitTestCase {
 	public function testSetHandlerState() {
-		$obj = new stdClass;
+		$obj = (object)[];
 		$state = new TrivialMediaHandlerState;
 		$this->assertNull( $state->getHandlerState( 'test' ) );
 		$state->setHandlerState( 'test', $obj );
diff --git a/tests/phpunit/unit/includes/skins/SkinFactoryTest.php b/tests/phpunit/unit/includes/skins/SkinFactoryTest.php
index 327b66a6fd4..d25ea45784e 100644
--- a/tests/phpunit/unit/includes/skins/SkinFactoryTest.php
+++ b/tests/phpunit/unit/includes/skins/SkinFactoryTest.php
@@ -90,7 +90,7 @@ class SkinFactoryTest extends \MediaWikiUnitTestCase {
 	 * @covers SkinFactory::makeSkin
 	 */
 	public function testMakeSkinWithValidSpec() {
-		$serviceInstance = new stdClass();
+		$serviceInstance = (object)[];
 
 		$serviceContainer = $this->createMock( ContainerInterface::class );
 		$serviceContainer->method( 'has' )->willReturn( true );