diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Proxy/SessionHandlerProxyTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Proxy/SessionHandlerProxyTest.php
index 1cf4aed06a..81c90433d7 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Proxy/SessionHandlerProxyTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Proxy/SessionHandlerProxyTest.php
@@ -127,7 +127,7 @@ class SessionHandlerProxyTest extends TestCase
      */
     public function testValidateId()
     {
-        $mock = $this->getMockBuilder(['SessionHandlerInterface', 'SessionUpdateTimestampHandlerInterface'])->getMock();
+        $mock = $this->getMockBuilder(TestSessionHandler::class)->getMock();
         $mock->expects($this->once())
             ->method('validateId');
 
@@ -142,7 +142,7 @@ class SessionHandlerProxyTest extends TestCase
      */
     public function testUpdateTimestamp()
     {
-        $mock = $this->getMockBuilder(['SessionHandlerInterface', 'SessionUpdateTimestampHandlerInterface'])->getMock();
+        $mock = $this->getMockBuilder(TestSessionHandler::class)->getMock();
         $mock->expects($this->once())
             ->method('updateTimestamp')
             ->willReturn(false);
@@ -156,3 +156,7 @@ class SessionHandlerProxyTest extends TestCase
         $this->proxy->updateTimestamp('id', 'data');
     }
 }
+
+abstract class TestSessionHandler implements \SessionHandlerInterface, \SessionUpdateTimestampHandlerInterface
+{
+}