response is an array of response

tests/PHPUnit/Integration/Core/CliMultiTest.php

@@ -136,7 +136,7 @@ class Core_CliMultiTest extends IntegrationTestCase
 
         $response = $this->cliMulti->request($urls);
 
-        $message = "Response was: " . substr($response, 0, 4000);
+        $message = "Response was: " . substr( implode("\n\n", $response), 0, 4000);
         $this->assertTrue(false !== strpos($response[0], '<meta name="generator" content="Piwik - Open Source Web Analytics"/>'), $message);
         $this->assertTrue(false !== strpos($response[0], 'Widgetize the full dashboard'). $message);
     }