diff --git a/tests/Grant/AuthCodeGrantTest.php b/tests/Grant/AuthCodeGrantTest.php
index 70682171..fc986568 100644
--- a/tests/Grant/AuthCodeGrantTest.php
+++ b/tests/Grant/AuthCodeGrantTest.php
@@ -1560,6 +1560,7 @@ class AuthCodeGrantTest extends TestCase
         $client = new ClientEntity();
         $client->setIdentifier('foo');
         $client->setRedirectUri('http://foo/bar');
+        $client->setIsConfidential();
         $clientRepositoryMock = $this->getMockBuilder(ClientRepositoryInterface::class)->getMock();
         $clientRepositoryMock->method('getClientEntity')->willReturn($client);
 
@@ -1633,6 +1634,7 @@ class AuthCodeGrantTest extends TestCase
         $client = new ClientEntity();
         $client->setIdentifier('foo');
         $client->setRedirectUri('http://foo/bar');
+        $client->setIsConfidential();
         $clientRepositoryMock = $this->getMockBuilder(ClientRepositoryInterface::class)->getMock();
         $clientRepositoryMock->method('getClientEntity')->willReturn($client);
 
@@ -1705,6 +1707,7 @@ class AuthCodeGrantTest extends TestCase
         $client = new ClientEntity();
         $client->setIdentifier('foo');
         $client->setRedirectUri('http://foo/bar');
+        $client->setIsConfidential();
         $clientRepositoryMock = $this->getMockBuilder(ClientRepositoryInterface::class)->getMock();
         $clientRepositoryMock->method('getClientEntity')->willReturn($client);