Update to drupal 8.0.0-rc1. For more information, see https://www.drupal.org/node/2582663

vendor/symfony/console/Tests/Fixtures/DummyOutput.php

@@ -0,0 +1,36 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Console\Tests\Fixtures;
+
+use Symfony\Component\Console\Output\BufferedOutput;
+
+/**
+ * Dummy output.
+ *
+ * @author Kévin Dunglas <dunglas@gmail.com>
+ */
+class DummyOutput extends BufferedOutput
+{
+    /**
+     * @return array
+     */
+    public function getLogs()
+    {
+        $logs = array();
+        foreach (explode("\n", trim($this->fetch())) as $message) {
+            preg_match('/^\[(.*)\] (.*)/', $message, $matches);
+            $logs[] = sprintf('%s %s', $matches[1], $matches[2]);
+        }
+
+        return $logs;
+    }
+}