<?php

namespace WyriHaximus\Ratchet\Tests\Event;

abstract class AbstractEventTest extends \PHPUnit_Framework_TestCase
{
    public function testEventConst()
    {
        $fqcn = static::FQCN;
        $this->assertInternalType('string', $fqcn::EVENT);
        $this->assertTrue(strlen($fqcn::EVENT) > 0);
    }

    public function testExtendsEvent()
    {
        $this->assertSame('Cake\Event\Event', (new \ReflectionClass(static::FQCN))->getParentClass()->getName());
    }
}

<?php

namespace WyriHaximus\Ratchet\Tests\Event;

abstract class AbstractEventTest extends \PHPUnit_Framework_TestCase
{
    public function testEventConst()
    {
        $fqcn = static::FQCN;
        $this->assertInternalType('string', $fqcn::EVENT);
        $this->assertTrue(strlen($fqcn::EVENT) > 0);
    }
}

--- 
+++ 
@@ -10,4 +10,9 @@
         $this->assertInternalType('string', $fqcn::EVENT);
         $this->assertTrue(strlen($fqcn::EVENT) > 0);
     }
+
+    public function testExtendsEvent()
+    {
+        $this->assertSame('Cake\Event\Event', (new \ReflectionClass(static::FQCN))->getParentClass()->getName());
+    }
 }
Make sure all events extend Event
