diff --git a/tests/Composer/Test/Mock/InstallationManagerMock.php b/tests/Composer/Test/Mock/InstallationManagerMock.php
index 1d1dfef8c..1a5f2c99b 100644
--- a/tests/Composer/Test/Mock/InstallationManagerMock.php
+++ b/tests/Composer/Test/Mock/InstallationManagerMock.php
@@ -16,6 +16,7 @@ use Composer\Installer\InstallationManager;
 use Composer\Repository\RepositoryInterface;
 use Composer\Repository\InstalledRepositoryInterface;
 use Composer\Package\PackageInterface;
+use Composer\IO\IOInterface;
 use Composer\DependencyResolver\Operation\InstallOperation;
 use Composer\DependencyResolver\Operation\OperationInterface;
 use Composer\DependencyResolver\Operation\UpdateOperation;
@@ -115,4 +116,9 @@ class InstallationManagerMock extends InstallationManager
     {
         return $this->uninstalled;
     }
+
+    public function notifyInstalls(IOInterface $io)
+    {
+        // noop
+    }
 }