From f66cb4a66f732cf1fd50214e4c8b13a5500d9323 Mon Sep 17 00:00:00 2001
From: Niklas Keller <me@kelunik.com>
Date: Sun, 15 May 2016 20:18:45 +0200
Subject: [PATCH] Check that factory returns an instance of LoopDriver

---
 src/Loop.php | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/Loop.php b/src/Loop.php
index eceb847..d29b989 100644
--- a/src/Loop.php
+++ b/src/Loop.php
@@ -54,7 +54,7 @@ final class Loop
     /**
      * Create a new driver if a factory is present, otherwise throw.
      *
-     * @throws \LogicException if no factory is set
+     * @throws \LogicException if no factory is set or no driver returned from factory
      */
     private static function createDriver()
     {
@@ -62,7 +62,13 @@ final class Loop
             throw new \LogicException("Can't create an event loop driver without a factory.");
         }
 
-        return self::$factory->create();
+        $driver = self::$factory->create();
+
+        if (!$driver instanceof LoopDriver) {
+            throw new \LogicException("LoopDriverFactory didn't return a LoopDriver.");
+        }
+
+        return $driver;
     }
 
     /**